Additions to the taxonomy of Pheidole (Hymenoptera: Formicidae) from the southern grasslands of Brazil

Abstract

The ant genus Pheidole is the most species-rich lineage of ants in the world and one of the dominant organisms in tropical regions. However, the knowledge of Pheidole diversity in the southern half of the Neotropical Region is fragmentary. Here, we offer contributions to the Pheidole taxonomy considering the species that occur in the grassland formations of South Brazil. The following species are revived from synonymy: P. idiota Santschi rev. stat., P. obscurior Forel rev. stat., P. paranana Santschi stat. rev. et n. stat. and P. strobeli Emery rev. stat. The following synonyms are proposed: P. idiota (= P. laticornis Wilson n. syn.), P. obscurior (= P. partita Mayr n. syn., = P. incisa evoluta Borgmeier n. syn.) and P. strobeli (= P. rufipilis divexa Forel n. syn., = P. nitidula daguerrei Santschi n. syn., = P. perversa Forel n. syn., = P. perversa richteri Forel n. syn., = P. strobeli misera Santschi n. syn.). Finally, six new species are described: P. abakytan n. sp., P. abaticanga n. sp., P. cangussu n. sp., P. curupira n. sp., P. mapinguari n. sp., and P. obapara n. sp.

Keywords:
Brazil; Neotropics; Campos Gerais; Myrmicinae; Pampas

Introduction

Among ant genera, Pheidole Westwood is the most species-rich with 1,151 species and 129 subspecies currently described (Bolton, 2020) and likely contains well over 1,500 species. Pheidole is a cosmopolitan genus, first diversifying in the New World approximately 29 Mya, with diversification in the Old World beginning around 11 Mya (Economo et al., 2019). More than 700 described Pheidole species inhabit the New World, with nearly 620 species recorded from the Neotropical Region and around 150 recognized in Brazil (AntWeb.org). Thanks to Wilson’s (2003) monograph, considered the most important single taxonomic contribution to the genus thus far, and the works by Longino (2009, 2019), our knowledge on diversity and taxonomy of Pheidole has increased significantly for the New World. However, as expected for such a hyperdiverse genus, recent works did not cover all the diversity for the genus and had particularly sparse coverage in some areas of the Neotropics. Among these, the Pheidole fauna of the southern half of South America is far from thoroughly documented.

Due to this knowledge deficit, it is expected that the biomes of Brazil harbor a high number of undescribed Pheidole species. Among Brazilian phytophysiognomies, the non-forest ecosystems (e.g. grasslands, savannas, shrublands, and open woodlands) are widespread. These ecosystems cover large portions of four different biomes (i.e. Caatinga, Cerrado, Pampa, and Pantanal) and occur to a lesser extent in other two forest biomes (i.e. Amazon Forest and Atlantic Rainforest) (Overbeck et al., 2015). In South Brazil, which encompasses the states of Rio Grande do Sul, Santa Catarina, and Paraná, the non-forest ecosystems are known as Campos Sulinos, and are naturally widespread over two different biomes, the Pampa in the southernmost region (Overbeck et al., 2007) and patches of grasslands within the Atlantic Forest in the northern portions (Andrade et al., 2016).

Grassland physiognomy in this region is not homogeneous and can vary strongly regarding vegetation coverage, elevation, and the anthropic influence (Overbeck et al., 2007). Campos Sulinos can be composed of noticeably short vegetation, mainly formed by grasses, to tall and complex vegetation composed by shrub and treelet species (Overbeck et al., 2007). The southern part of the grasslands in Brazil encompasses the Pampa biome, an open ecosystem with an average elevation of 800 m a.s.l., exclusive for the state of Rio Grande do Sul in Brazil and also distributed in Argentina and Uruguay. This is considered one of the most species-rich grasslands in the world, despite being more intensively grazed when compared to the highland grasslands of Santa Catarina and Paraná that are included in the Atlantic Forest biome (Overbeck et al., 2007; Dröse et al., 2017). The highland grasslands in the Atlantic Forest biome are mainly distributed from about 800 to 1,000 m a.s.l., with highest peaks up to 1,800 m, eventually forming mosaics with Araucaria forests (Andrade et al., 2016).

In the Paraná state, the non-forested ecosystems, commonly referred as Campos Gerais (Franco & Feitosa 2018), are characterized by the combination of savannas (Cerrado), in the northern portion, and open grasslands permeated by gallery forests with Araucaria angustifolia (Bertol.) Kuntze covering rocky soil with canyons, caves, and shallow rivers (Maack, 1981; Melo et al., 2001). Additionally, these highland grasslands are adapted to frequent burnings concentrated at the end of the winter, resulting in a dominance of highly fire-resilient grass tussock species (Boldrini, 2009).

In the recent years, ant surveys have been conducted in the Brazilian southern grasslands in Paraná (e.g. Franco & Feitosa 2018; Martins et al., 2020), Santa Catarina (e.g. Martins et al., 2020), and Rio Grande do Sul (e.g. Diehl et al., 2005; Albuquerque & Diehl, 2009; Pinheiro et al., 2010; Rosado et al., 2012; Diehl et al., 2014; Dröse et al., 2017), all of them revealing a considerable number of unidentified Pheidole species. Several limitations have led to this taxonomic impediment, including: (1) the absence of a comprehensive and user-friendly key to the identification of the Brazilian Pheidole species, (2) the difficulty in understanding the species limits within the genus, (3) and the high number of undescribed species from the southern part of the Neotropics.

Besides the species described by Longino (2009, 2019) from the Mesoamerican fauna, a single Pheidole species was recently described from Bahia in Brazil (Pheidole protaxiOliveira, et al., 2015). Thus, considering the scarcity of taxonomic studies on Pheidole in the southernmost areas of the Neotropical Region, and the accumulation of specimens from recent surveys, here we offer additions to the taxonomy of Pheidole known from natural grasslands of South Brazil. To visually improve the taxonomic descriptions, we provide images, 3D models, and 3D videos based on surface volume renderings of microtomography (micro-CT) scans for all new species. A synopsis of the species recognized for these environments is also provided, as well as updated taxonomic keys based on Wilson’s (2003) monography. This is the first study focusing on the Pheidole species from a single ecosystem in Brazil.

Methods

Specimen examination and imaging

The specimens examined here were obtained from different published and ongoing surveys carried out in the natural grasslands of South Brazil (Dröse et al., 2017; Franco & Feitosa 2018; Dröse et al., 2019; Martins et al., 2020) and sent for identification and/or deposit in the Coleção Entomológica Padre Jesus Santiago Moure of the Universidade Federal do Paraná (DZUP). Also, to improve our species delimitation hypotheses and examine type-specimens, we have visited some of the most representative ant collections for Pheidole in the New World, including the Museu de Zoologia da Universidade de São Paulo, the myrmecological collection of the Centro de Pesquisas do Cacau in Bahia, and the Museum of Comparative Zoology of the Harvard University, Cambridge. In total, approximately 1,550 specimens were examined.

A considerable part of the material examined here derives mainly from three large projects carried out in South Brazil, of which voucher specimens were deposited in DZUP. The first project, coordinated by RMF at the Laboratório de Sistemática e Biologia de Formigas (UFPR), aimed a comprehensive survey of the ant fauna inhabiting the natural savannas and grasslands of the state of Paraná. In this project, ants were collected using pitfall traps and Winkler extractors in four different reserves of the state, representing the first standardized inventory of ants in the natural grasslands of Paraná (for further details see Franco & Feitosa (2018)).

The second project, namely SiSBiota, was conducted by Embrapa Floresta (Colombo, Paraná, Brazil) and the Universidade Estadual de Santa Catarina (UDESC). This project focused on verifying the effect of different land use systems on the composition of epigaeic and hypogaeic invertebrates. Samplings encompassed several vegetational formations, including natural and anthropic grasslands (Martins et al., 2020). In total, ants were collected in seven municipalities with representative areas of grasslands, one in the Paraná state, and six in the Santa Catarina state.

The last project, developed by the research group of the Laboratório de Ecologia de Interações of Universidade Federal do Rio Grande do Sul (UFRGS), investigated how ant communities are locally assembled in natural forest-grassland ecotones distributed over the south Brazilian region (Dröse et al., 2017, 2019). In this project, a total of six natural grassland areas under traditional cattle grazing in the state of Rio Grande do Sul were sampled.

Examinations were made at 80x magnification with a Zeiss SteREO DiscoveryV8 dissecting microscope. High-resolution images were obtained with an Axiocam 305 color coupled in Zeiss SteREO Discovery.V20, extended depth focus was made in the software Zen Blue v.2.6, and subsequently treated to correct for brightness and contrast.

X-ray micro-computed tomography and 3D images

The use of Micro-CT in systematic and taxonomic research is becoming more common. Recent studies have demonstrated its utility for generating high-resolution, virtual, and interactive three-dimensional reconstructions of whole ant specimens (e.g. Fischer et al., 2016; Sarnat et al., 2016; Hita Garcia et al., 2017). One of the main advantages of the approach is the generation of an openly available cybertype dataset to accompany the physical type, thus protecting the original exemplar from deterioration (Faulwetter et al., 2013; Hita Garcia et al., 2017). Here, micro-CT/μCT scans were created with a ZEISS Xradia 510 Versa and the ZEISS Scout and Scan Control System software. Scan settings were selected according to yield optimum scan quality: 4x objective, exposure times between 0.6 and 3 seconds, source filter “Air’, voltage between 40 and 50 kV, power between 3 and 4W, and field mode “normal’ (Table 1). The combination of voltage, power and exposure time was set to yield intensity levels of between 15,000 and 17,000 across the whole specimen. Scan times varied from 27 to 50 minutes, depending on exposure times. Full 360-degree rotations were done with a number of 801 projections. The resulting scans have resolutions of 1013x992x999 (HxWxD) pixels and voxel sizes range between 2.25 μm and 5.39 μm. 3D reconstruction of the resulting scans was done with XMReconstructor and saved in DICOM file format.

Table 1
Overview of micro-CT scanning data presenting specimen data, scan settings, and voxel sizes for the resulting scans (all specimens are workers and all files are in DICOM format).

Species	Identifier	Sub-caste	Type Status	Magnification (x)	Exposure (s)	Voxel size (µm)	Voltage (kV)	Power (W)	Amperage (µA)
abakytan	CASENT0742943	major	Holotype	4	0.7	3.8151	50	4	80
abakytan	CASENT0742944	minor	Paratype	4	0.6	3.2144	50	4	79
abaticanga	CASENT0790160	major	Holotype	4	1.5	2.8127	40	3	75
abaticanga	CASENT0790161	minor	Paratype	4	1	2.2503	50	4	80
cangussu	CASENT0742941	major	Holotype	4	3	5.3997	50	4	80
cangussu	CASENT0742942	minor	Paratype	4	0.6	3.0684	50	4	80
curupira	CASENT0742949	major	Holotype	4	2	5.0622	50	4	79
curupira	CASENT0742950	minor	Paratype	4	1	3.3751	40	3	75
mapinguari	CASENT0742947	major	Holotype	4	1	4.8208	50	4	80
mapinguari	CASENT0742947	minor	Paratype	4	0.9	3.3751	40	3	75
obapara	CASENT0790158	major	Holotype	4	1.2	3.0684	40	3	74
obapara	CASENT0790159	minor	Paratype	4	1.1	2.411	50	4	79

The 3D surface models were generated with InVesalius (2016) v3.1.1 software (de Moraes et al., 2011), an open-source software for 3D reconstruction developed by Centro de Tecnologia da Informação Renato Archer – CTI and available online. All models were posteriorly simplified, corrected, and filmed using MeshLab v.2016 (Cignoni et al., 2008) and Blender v2.80 (Blender, 2019).

Taxonomic procedures

Taxonomic units (morphospecies) were delimited using characters of external morphology such as body shape, surface sculpturing, and pilosity. The delimited morphospecies were compared with the type material of valid species and junior synonyms to confirm their identities. All morphospecies not corresponding to available names were described as new, and for those that have been recognized among synonyms, the name status was revived. The revived species were redescribed so that the important features for each one could be updated and standardized. LucidBuilder software (LucidTeam) was used to generate a list of characters, which served as the basis for the descriptions in a semiautomatic method.

The taxonomic synopsis of the Pheidole species in Brazilian southern grasslands includes new species and species with revived status, and also the previously published records for this region (Diehl et al., 2005; Pinheiro et al., 2010; Rosado et al., 2012; Dröse et al., 2017; Franco & Feitosa, 2018; Dröse et al., 2019, Martins et al., 2020; see Fig. 13, 14, 15, 16, 17, 18).

Figure 13
Map of South Brazil showing the localities for the aberrans group species records in grassland areas.

Figure 14
Map of South Brazil showing the localities for the diligens group species records in grassland areas.

Figure 15
Map of South Brazil showing the localities for the fallax group species records in grassland areas.

Figure 16
Map of South Brazil showing the localities for the flavens group species records in grassland areas.

Figure 17
Map of South Brazil showing the localities for the gertrudae group species records in grassland areas.

Figure 18
Map of South Brazil showing the localities for the tristis group species records in grassland areas.

Considering the noteworthy diversity of Pheidole and the limitations of making available an identification key that included only the species of this study, we included the species treated here in the last couplet required to access them in the keys provided by Wilson (2003).

Measurements and index abbreviations

Measurements were adapted from Sarnat et al. (2016) and Longino (2019) and were taken from at least one specimen of each worker subcaste. Specimens were measured with a dual-axis micrometer stage with output in increments of 0.001 mm. All measurements are presented in mm.

ELEye length. Maximum eye length in lateral view.

FLMetafemur length. Length of metafemur measured along its long axis.

HLHead length. Maximum distance from the midpoint of the anterior clypeal margin to the midpoint of the posterior margin of the head, measured in full-face view. In majors, measured from midpoint of tangent between the anterior-most position of clypeus to midpoint of tangent between the posterior-most projection of posterolateral lobes.

HWHead width. Maximum width of the head in full-face view, excluding the eyes.

MLMesosomal length. Maximum length of mesosoma measured in lateral view as the diagonal length of the mesosoma from the point at which the pronotum meets the cervical shield to the apex of the propodeal lobe.

PeWPetiole width. Maximum width of the petiole measured in dorsal view.

PeLPetiole length. Maximum length of petiole measured from anteroventral junction with propodeum to posterodorsal junction with postpetiole.

PpWPostpetiole width. Maximum width of the postpetiole measured in dorsal view.

SLScape length. Length of the antennal scape, including the lamella encircling the base of the scape but excluding the basal condyle.

IHPInner hypostomal projection. Distance measured between the inner hypostomal projection in ventral view considering the approximate midpoint of the base of the projection. Apply to major workers and queens.

OHPOuter hypostomal projection. Distance measured between the outer hypostomal projection in ventral view considering the approximate midpoint of the base of the projection. Apply to major workers and queens.

CICephalic index. HW/HL × 100.

SIScape index. SL/HW × 100.

HPIHypostomal projections index. IHT/OHT × 100.

Terminology

The terminology follows Wilson (2003) and Longino (2019) for the morphological structures, Wilson (1955) for pilosity, and Wilson (2003) and Longino (2019) for surface sculpturing. Regarding the latter, a common sculpture pattern in Pheidole is the areolate one. In some cases, it can be superficially marked and hardly recognized; however, it can be seen by using indirect light. Major and minor workers are referred as ♃ and ☿ in the examined material, respectively.

Repositories

Collections are referred to by the following acronyms, which follow the Insect and Spider Collections of the World website (http://hbs.bishopmuseum.org/codens/):

DZUP Coleção Entomológica Padre Jesus Santiago Moure of the Universidade Federal do Paraná, Curitiba, Brazil.

MCZC Museum of Comparative Zoology, Cambridge, MA, USA.

MHNG Muséum d'Histoire Naturelle, Geneva, Switzerland.

MSNG Museo Civico di Storia Naturale “Giacomo Doria’, Genova, Italy.

MZSP Museu de Zoologia da Universidade de São Paulo, São Paulo, Brazil.

NHMB Naturhistorisches Museum, Basel, Switzerland.

NHMW Naturhistorisches Museum Wien, Wien, Austria.

Data availability

All the type specimens examined in this study have been databased and the data is freely accessible on AntWeb (http://www.antweb.org; AntWeb, 2020). Each specimen can be traced by a unique specimen identifier attached to its pin (e.g. CASENT0764125). The Cybertype datasets provided in this study consist of the full micro-CT original volumetric datasets, 3D model in PLY and STL formats, and 3D rotation video files. All data are freely available in the supplementary material on http://doi.org/10.6084/m9.Fighare.9775895.

Taxonomic synopsis of the Pheidole species in Brazilian southern grasslands

aberrans group

Pheidole aberrans Mayr, 1868

= Pheidole aberrans diversiceps Santschi, 1916

= Pheidole aberrans fartilia Forel, 1913

= Pheidole aberrans mutica Emery, 1906

Pheidole cavifrons Emery, 1906

= Pheidole arciruga Forel, 1908

= Pheidole cavifrons fuscipunctis Santschi, 1916

diligens group

Pheidole abakytan new species

Pheidole idiota Santschi, 1923 revived status

= Pheidole laticornis Wilson, 2003 new synonym

=Pheidole vafra idiota maculifrons Santschi, 1929

Pheidole nubila Emery, 1906

Pheidole oxyops Forel, 1908

= Pheidole genalis Borgmeier, 1929

= Pheidole oxyops regia Forel, 1908

Pheidole paranana Santschi, 1925 revived status et new status

Pheidole pubiventris Mayr, 1887

= Pheidole indistincta Forel, 1899

= Pheidole pubiventris cearensis Forel, 1901

= Pheidole pubiventris nevadensis Forel, 1901

= Pheidole pubiventris timmii Forel, 1901

= Pheidole variegata Emery, 1896

Pheidole radoszkowskii Mayr, 1884

= Pheidole australis Emery, 1890

= Pheidole medialis Wilson, 2003

= Pheidole radoszkowskii acuta Emery, 1894

= Pheidole radoszkowskii luteola Forel, 1893

= Pheidole radoszkowskii opacissima Forel, 1901

= Pheidole radoszkowskii parvinoda Forel, 1912

Pheidole triconstricta Forel, 1886

= Pheidole radoszkowskii discursans Forel, 1912

= Pheidole radoszkowskii saviozae Forel, 1911

= Pheidole triconstricta ambulans Emery, 1906

= Pheidole triconstricta hebe Santschi, 1923

= Pheidole triconstricta rosariensis Forel, 1913

Pheidole vafra Santschi, 1923

fallax group

Pheidole acutidens (Santschi, 1922)

Pheidole fallax Mayr, 1870

= Pheidole columbica Forel, 1886

= Pheidole fallax britoi Forel, 1912

= Pheidole fallax ovalis Forel, 1912

= Pheidole fallax rubens Forel, 1899

= Pheidole jelskii fallacior Forel, 1901

Pheidole humeridens Wilson, 2003

Pheidole jelskii Mayr, 1884

= Pheidole fallax emiliae Forel, 1901

= Pheidole jelskii antillensis Forel, 1901

= Pheidole jelskii arenicola Emery, 1894

Pheidole mapinguari new species

Pheidole nitidula Emery, 1888

= Pheidole strobeli silvicola Borgmeier, 1927

Pheidole obscurior Forel, 1886 revived status

= Pheidole incisa evoluta Borgmeier, 1929 new synonym

= Pheidole partita Mayr, 1887 new synonym

Pheidole obscurithorax Naves, 1985

Pheidole pampana Santschi, 1929

Pheidole strobeli Emery, 1906 revived status

= Pheidole nitidula daguerrei Santschi, 1931 new synonym

= Pheidole perversa Forel, 1908 new synonym

=Pheidole perversa richteri Forel, 1909 new synonym

=Pheidole rufipilis divexa Forel, 1908 new synonym

=Pheidole strobeli misera Santschi, 1916 new synonym

Pheidole valens Wilson, 2003

flavens group

Pheidole abaticanga new species

Pheidole breviseta Santschi, 1919

Pheidole obtusopilosa Mayr, 1887

gertrudae group

Pheidole gertrudae Forel, 1886

= Pheidole gertrudae leonhardi Forel, 1901

= Pheidole gertrudae loretensis Santschi, 1933

= Pheidole humilis (Borgmeier, 1930)

transversostriata group

Pheidole obapara new species

tristis group

Pheidole cangussu new species

Pheidole curupira new species

Pheidole fimbriata Roger, 1863

= Pheidole diversa Smith, 1860

= Pheidole fimbriata tucumana Forel, 1913

= Pheidole smithii Dalla Torre, 1892

= Pheidole soesilae Makhan, 2007

Pheidole heyeri Forel, 1899

= Pheidole guilelmimuelleri ultrix Forel, 1912

Pheidole rosae Forel, 1901

= Pheidole silvestrii Emery, 1906

Pheidole spininodis Mayr, 1887

= Pheidole hohenlohei Emery, 1888

= Pheidole spielbergi Emery, 1888

= Pheidole spininodis bruta Santschi, 1934

= Pheidole spininodis lucifuga Santschi, 1923

= Pheidole spininodis pencosensis Forel, 1914

= Pheidole spininodis solaris Santschi, 1929

Pheidole subarmata Mayr, 1884

= Pheidole cornutula Emery, 1890

= Pheidole cornutula dentimentum Santschi, 1929

= Pheidole cornutula imbecilis Emery, 1906

= Pheidole hondurensis Mann, 1922

= Pheidole subarmata borinquensis Wheeler, 1908

= Pheidole subarmata elongatula Forel, 1893

= Pheidole subarmata nassavensis Wheeler, 1905

= Pheidole subarmata nefasta Santschi, 1929

Additions to Wilson (2003) keys based on the nomenclatural acts of this study:

Key to the species in the diligens group

44 Major: all of dorsal surface of head capsule except vertexal area areolate and opaque; all of frontal lobes and region between them posterior to the frontal triangle covered by parallel longitudinal rugulae…………..…....44a

– Major: at most only the anterior half of the dorsal head surface sculptured....…44b

44a Major: pronotal dorsum areolate...…......….....…………………….Pheidole nubila

– Major: pronotal dorsum reticulate-rugose…................................................Pheidole paranana rev. stat. et n. stat.

44b Major: a wide central space between frontal carinae smooth and shiny….…...….45

– Major: space between frontal carinae covered by parallel longitudinal rugulae………………………...………………….Pheidole abakytan n. sp.

51 Major: longitudinal rugulae immediately mesad to eyes reaching halfway to vertexal margin, sides of mesonotum and propodeum with few rugulae…………………………………………………………………...51a

– Major: longitudinal rugulae immediately mesad to eyes reaching only one-fourth distance to vertexal margin, sides of mesonotum and propodeum lacking rugulae…………………………………….....…….……Pheidole pampana

51a Major: clypeal disc with a median rugula..………..……………Pheidole laevinota

– Major: clypeal disc smooth…………………..………...Pheidole strobeli rev. stat.

91 Major: dorsal surface of head and pronotum, in side view, covered by dense standing hairs…………………………….………………..……………..91a

– Major: dorsal surface of head and pronotum, in side view, with sparse pilosity………………………………....……………...Pheidole mooreorum

91a Major: antennal scape basally terete……….……..………Pheidole idiota rev. stat.

– Major: antennal scape basally thin……………………….....……….Pheidole vafra

Key to the species in the fallax group

102 Major: dorsum and sides of propodeum lacking carinulae………….………..102a

– Major: dorsum and sides of propodeum covered by carinulae….…………..…103

102a Major: pronotum completely covered by transverse rugulae…………………………………………………….….…Pheidole alienata

– Major: only the anterior face of the pronotum with few transverse rugulae………………………..……………....Pheidole mapinguari n. sp.

103 Major: the strip of head dorsum posterior to the frontal triangle lacking rugulae, smooth and shiny………………………………………………..…….103a

– Major: the strip of head dorsum posterior to the frontal triangle covered by longitudinal rugulae all the way mesad to the midline of the head……………………………………………………………….…….104

103a Major: humerus, in dorsal-oblique view, subangulate………...Pheidole laevinota

– Major: humerus, in dorsal-oblique view, rounded…….Pheidole strobeli rev. stat.

Key to the species in the flavens group

4 Major: in side view, space immediately laterad to eye reticulate-rugose. Minor: posterior half of head reticulate-rugose…………….…….Pheidole verricula

– Major: in side view, space immediately laterad to eye with any other combination of sculpture instead of reticulate-rugose. Minor: posterior half of head areolate, not reticulate-rugose………………………………………….…..4a

4a Major: clypeal disc overlain with several rugulae……………Pheidole obtusopilosa

– Major: clypeal disc smooth and shiny………………..….Pheidole abaticanga n. sp.

Key to the species in the transversostriata group

3 Major: in side view, profile of head not “dented’ by a strong concavity just anterior to the vertex, instead forming a smooth, continuous convexity…………………………………………Pheidole transversostriata

– Major: in side view, profile of head “dented’ by a strong convexity just anterior to the vertex…………………………………………………………………..3a

3a Major: space between eye and antennal fossa with longitudinal rugulae only……...4

– Major: space between eye and antennal fossa reticulate-rugose……………………………………………….Pheidole obapara n. sp.

Key to the species in the tristis group

16 Major: in side view, profile of mesonotal convexity triangular, with an acute apex………………………………………………………………………16a

– Major: in side view, profile of mesonotal convexity surmounted by at most a low secondary convexity…………………………………………………..…..17

16a Major: hypostomal margin with five teeth. Minor: seen from above and obliquely, propodeal projection reduced to an obtuse angle formed by the two propodeal faces………………………………………….Pheidole cornicula

– Major: hypostomal margin with four teeth, without the median tooth. Minor: seen from above and obliquely, propodeal projection developed as a well-formed triangular projection...………………..…..Pheidole cangussu n. sp.

74 Major: propodeal dorsum lacking rugulae, smooth to finely areolate………………………………..………………………..Pheidole manuana

– Major: propodeal dorsum covered with transversal rugulae……..……………..74a

74a Major: humerus overlain with few rugulae……………………..….…………….75

– Major: humerus smooth and shiny………….……………Pheidole curupira n. sp.

Species accounts

Pheidole abakytan n. sp.

urn:lsid:zoobank.org:act:8791EB98-2D7F-4ABD-808E-F069754CAC43

(Fig. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)

Figure 1
Pheidole abakytan n. sp. Major worker, holotype, CASENT0742943: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0742944: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.5 mm. 3D model and rotation video (Supp 1 and 2 [online only]).

Figure 2
Pheidole abaticanga n. sp. Major worker, holotype, CASENT0790160: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0790161: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.2 mm. 3D model and rotation video (Supp 3 and 4 [online only]).

Figure 3
Pheidole cangussu n. sp. Major worker, holotype, CASENT0742941: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0742942: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.5 mm. 3D model and rotation video (Supp 5 and 6 [online only]).

Figure 4
Pheidole curupira n. sp. Major worker, holotype, CASENT0742949: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0742950: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.5 mm. 3D model and rotation video (Supp 7 and 8 [online only]).

Figure 5
Pheidole idiota rev. stat. Major worker, syntype, CASENT0913471: (A) full-face view (B) lateral view (C) dorsal view. Minor worker, syntype, CASENT0913472: (D) full-face view (E) profile view (F) dorsal view. Image font: AntWeb.org; photographer: Will Ericson.

Figure 6
Pheidole mapinguari n. sp. Major worker, holotype, CASENT0742947: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0742948: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.5 mm. 3D model and rotation video (Supp 9 and 10 [online only]).

Figure 7
Pheidole obapara n. sp. Major worker, holotype, CASENT0790158: (A) full-face view (B) lateral view (C) hypostomal margin (D) dorsal view. Minor worker, paratype, CASENT0790159: (E) full-face view (F) profile view (G) dorsal view. Scale bar 0.2 mm. 3D model and rotation video (Supp 11 and 12 [online only]).

Figure 8
Pheidole obscurior rev. stat. Major worker, lectotype, JTLC000015316: (A) full-face view (B) lateral view (C) dorsal view. Minor worker, paralectotype, JTLC000015317: (D) full-face view (E) profile view (F) dorsal view. Image font: AntWeb.org; Photographer: John T. Longino.

Figure 9
Pheidole paranana rev. stat. et n. stat. Major worker, syntype, CASENT0913465: (A) full-face view (B) lateral view (C) dorsal view. Minor worker, syntype, CASENT0913466: (D) full-face view (E) profile view (F) dorsal view. Image font: AntWeb.org; photographer: Will Ericson.

Figure 10
Pheidole strobeli rev. stat. Major worker, syntype, CASENT0904388: (A) full-face view (B) lateral view (C) dorsal view. Minor worker, syntype, CASENT0904389: (D) full-face view (E) profile view (F) dorsal view. Image font: AntWeb.org; photographer: Zach Lieberman.

Figure 11
Map of South Brazil showing the localities for the new Pheidole species described here.

Holotype major worker: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 917m, 24°11'15.9’S 49°39'53.1’W, 15.i.2015 A. M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos cols. [CASENT0742943] [DZUP]

Paratype five major and seven minor workers:same data as holotype [DZUP (2 ♃ and 2 ☿; DZUP549878, DZUP549879, DZUP549882, and CASENT0742944); MCZC (2 ♃ and 2 ☿; DZUP549875, DZUP549876, DZUP549880, and DZUP549881); MZSP (1 ♃ and 2 ☿; DZUP549877, DZUP549883, and DZUP549884)]

Cybertypes: holotype, major worker (CASENT0742943) (Supp 1 [online only]) and paratype, minor worker (CASENT0742944) (Supp 2 [online only]), with label transcribed above.

Geographic range. Brazil: Paraná.

Measurements, major worker: EL: 0.18; FL: 0.83 – 0.92; HL: 1.20 – 1.28; HW: 1.08 – 1.16; IHP: 0.38 – 0.40; ML: 1.10 – 1.20; OHP: 0.45 – 0.50, PeL: 0.38 – 0.43; PeW: 0.14 – 0.15; PpL: 0.18 – 0.20; PpW: 0.22 – 0.23; PsL: 0.08; SL: 0.85 – 0.92; CI: 90 – 91; SI: 76 – 81; HPI: 80 – 83 (n = 3).

Major worker. Head: head side, in dorsal view, broadly convex, with dense appressed setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin deeply emarginate. Hypostoma with median tooth vestigial; inner teeth distinct, narrow and slightly curved, converging apically, and widely spaced. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, with a combination of appressed setae and standing. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally strongly areolate with a reticulate-rugose area anteriorly, and promesonotal dorsum, in lateral view, presenting two pairs of stiff standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin narrowly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting stiff standing setae, two of them longer than the adjacent. First gastral tergum finely areolate; dorsally with a combination of stiff standing and appressed setae, no more than 1.5× the eye length. Color reddish-brown.

Measurements, minor worker: EL: 0.13; FL: 0.65 – 0.73; HL: 0.63 – 0.70; HW: 0.50 – 0.60; ML: 0.80 – 0.93; PeL: 0.24 – 0.30; PeW: 0.10 – 0.13; PpL: 0.10 – 0.15; PpW: 0.14 – 0.18; PsL: 0.04 – 0.05; SL: 0.83 – 0.88; CI: 80 – 86; SI: 146 – 165 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, not visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina strongly areolate, with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae finely areolate with a smooth median patch. Vertexal surface finely areolate. Mesosoma: pronotal surface strongly areolate, dorsally with a reticulate-rugose patch anteriorly, and promesonotal dorsum, in lateral view, presenting two pairs of stiff standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection triangular; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with straight side, dorsally smooth, and presenting a combination of a pair of stiff standing setae, with shorter and appressed setae. First gastral tergum smooth; dorsally with a combination of stiff standing and appressed setae, no more than 1.5× the eye length. Color reddish-brown.

Comments. Similar species are P. laevifrons Mayr, P. lemur Forel, and P. zelata Wilson. All these species, which are included in the diligens group, present majors with lateral margins of the head with appressed setae, space between eye and frontal carina with a small reticulate-rugose patch, and vertexal surface smooth. Pheidole abakytan can be differentiated from P. laevifrons by first gastral tergum with a combination of stiff standing and appressed setae, while in P. laevifrons these setae are flexuous. Pheidole lemur has the first gastral tergum finely areolate, and P. abakytan has a smooth gastral surface. The main difference between P. zelata and P. abakytan is that the propodeal projection is spiniform in P. zelata while in P. abakytan this projection is triangular. Minors of P. abakytan have the head surface predominantly areolate, and in P. laevifrons and P. zelata the surface is smooth.

This species was collected in pitfall traps in a savanna area at 917 m. The type-locality, Parque Estadual do Cerrado in Jaguariaíva, Paraná state, represents the southernmost fragment of the Cerrado biome in Brazil, where the prevailing vegetation are the open woodlands.

Etymology. From Tupi-Guarani, Old Tupi, ába = hair, akytan of akytã = short (de Carvalho, 1987), in apposition, referring to the hairs on the head of the major worker. The Old Tupi (also known as as língua brasílica “Brazilian language’) was the main language spoken by the ethnic groups that inhabited the Brazilian coast before the conquest by the Portuguese settlers. Vocabulary available on http://www.oocities.org/indianlanguages_2000/.

Pheidole abaticanga n. sp.

urn:lsid:zoobank.org:act:045B6A90-1854-40A0-AEFF-DE2FE3799B61

(Fig. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)

Holotype major worker: Brazil: PR, Tibagi, P.E. do Guartelá, 24°33'49.61’S 50°15'32.36’W, 20-25.ix.2015 W. Franco, R.M. Feitosa, A. Machado cols. [CASENT0790160] [DZUP]

Paratype five major and three minor workers:same data as holotype [DZUP (1 ♃ and 1 ☿; DZUP549885 and CASENT0790161); MCZC (2 ♃ and 1 ☿; DZUP549888, DZUP549889, and DZUP549891); MZSP (2 ♃ and 1 ☿; DZUP549886, DZUP549887, and DZUP549890)]

Cybertypes: holotype, major worker (CASENT0790160) (Supp 3 [online only]) and paratype, minor worker (CASENT0790161) (Supp 4 [online only]), with label transcribed above.

Geographic range. Brazil: Paraná.

Measurements, major worker: EL: 0.08 – 0.10; FL: 0.46 – 0.48; HL: 0.86 – 0.95; HW: 0.78 – 0.83; IHP: 0.12 – 0.14; ML: 0.62 – 0.68; OHP: 0.30, PeL: 0.26 – 0.28; PeW: 0.12 – 0.14; PpL: 0.14 – 0.16; PpW: 0.22 – 0.24; PsL: 0.06 – 0.08; SL: 0.38 – 0.40; CI: 87 – 91; SI: 45 – 49; HPI: 40 – 47 (n = 3).

Major worker. Head: head side, in dorsal view, slightly convex, nearly straight, with standing setae; head dorsal profile with a strong convexity just anterior to the vertexal region, and vertexal margin deeply emarginate. Hypostoma with median tooth vestigial; inner teeth distinct and broad, in mid-distance from outer teeth. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, not surpassing midheight between eye and vertexal margin, with standing setae. Space between eye and frontal carina reticulate-rugose, with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae longitudinally rugulose that gradually become reticulate-rugose at about the posterior half of head dorsum. Vertexal surface, in frontal view, strongly reticulate-rugose. Mesosoma: pronotum dorsally reticulate-rugose, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, without an anterior concavity and with a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, apically narrow and rounded. Postpetiole, in dorsal view, wider than long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, more than 1.5× the eye length. Color light yellow.

Measurements, minor worker: EL: 0.05 – 0.06; FL: 0.32; HL: 0.43; HW: 0.38 – 0.40; ML: 0.44; PeL: 0.19 – 0.21; PeW: 0.08; PpL: 0.10 – 0.11; PpW: 0.13; PsL: 0.05; SL: 0.33; CI: 89 – 93; SI: 84 – 88 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, emarginate and rounded; occipital carina, in dorsal view, not visible; postgenal bridge, in lateral view, areolate. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina strongly areolate, with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae strongly areolate. Vertexal surface strongly areolate. Mesosoma: pronotal surface strongly areolate, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile continuous, without a distinctly produced median area, and dropping almost vertically to the propodeum. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with smoothly rounded side, dorsally smooth, and presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light yellow.

Comments. Majors can be differentiated from similar species in the flavens group by the head dorsal profile anteriorly convex and depressed near the vertexal portion, and the head surface strongly reticulate-rugose, including the space between eye and antennal fossa, frons, and vertexal surface. Minors of P. abaticanga are similar to several species included the flavens group, so that the complete description must be employed to distinguish it.

The type-series of this species was collected in a leaf-litter sample at a small fragment of semideciduous forest near a stream. The type-locality, Parque Estadual do Guartelá, Tibagi, is one of the last well-preserved remnants of the grassland formation known as Campos Gerais, exclusively found in the Paraná state, within the Atlantic Forest domain. The landscape consists of large areas of grasslands and shrublands with small enclaves of semideciduous forests.

Etymology. From Tupi-Guarani, Old Tupi (see details about the language at the description of P. abakytan above), abati = corn, canga of akánga = head (de Carvalho, 1987), in apposition, referring to the head shape of the major worker. This name was chosen for the way that my labmate Mila Martins typically recognizes and diagnoses this species.

Pheidole cangussu n. sp.

urn:lsid:zoobank.org:act:93B2A93C-F8FA-4DAB-B209-E986F7C6B9E2

(Fig. 3, 4, 5, 6, 7, 8, 9, 10, 11)

Holotype major worker: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 804m, 24°10'04.7’S 49°39'59.8’W, 15.i.2005 A. M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos cols. [CASENT0742941] [DZUP]

Paratype one major and 11 minor workers:same data as holotype [DZUP (8 ☿; DZUP549893, DZUP549897, DZUP549898, DZUP549899, DZUP549900, DZUP549901, DZUP549902, and CASENT0742942); MCZC (2 ☿; DZUP549896 and DZUP549895); MZSP (1 ♃ and 1 ☿; DZUP549892 and DZUP549894)]

Cybertypes: holotype, major worker (CASENT0742941) (Supp 5 [online only]) and paratype, minor worker (CASENT0742942) (Supp 6 [online only]), with label transcribed above.

Additional material: two ♃ and four ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Limpo, 25º14'52.74’S 49º59'35.01’W, 24-28.XI.2014, W. Franco, R.M. Feitosa, A.C. Ferreira, F. Benatti cols. [DZUP].

Geographic range. Brazil: Paraná.

Measurements, major worker: EL: 0.18 – 0.20; FL: 1.12 – 1.16; HL: 1.84; HW: 1.44 – 1.52; IHP: 0.30 – 0.36; ML: 1.44 – 1.60; OHP: 0.68, PeL: 0.50; PeW: 0.20 – 0.22; PpL: 0.34 – 0.38; PpW: 0.34 – 0.38; PsL: 0.08 – 0.13; SL: 0.64 – 0.76; CI: 78 – 83; SI: 44 – 50; HPI: 44 – 53 (n = 2).

Major worker. Head: head side, in dorsal view, broadly convex, with standing setae; head dorsal profile forming a smooth, continuous convexity, nearly straight, and vertexal margin deeply emarginate. Hypostoma with median tooth absent; inner teeth distinct and broad, diverging apically. Median clypeal carina distinct; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, not surpassing midheight between eye and vertexal margin, with standing setae, and anterior margin with some of them longer than the adjacent. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae longitudinally rugulose. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally smooth, and promesonotal dorsum, in lateral view, presenting stiff standing setae. Mesonotal profile continuous, with a distinctly produced median area. Katepisternum finely areolate with smooth median patch and few rugulae. Propodeal projection triangular. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, apically narrow and acute. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting stiff standing setae. First gastral tergum smooth; dorsally with stiff standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Measurements, minor worker: EL: 0.13; FL: 0.63 – 0.65; HL: 0.65 – 0.70; HW: 0.60 – 0.62; ML: 0.90; PeL: 0.30 – 0.33; PeW: 0.10; PpL: 0.18 – 0.28; PpW: 0.14 – 0.16; PsL: 0.03; SL: 0.58 – 0.65; CI: 86 – 92; SI: 96 – 108 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface smooth. Mesosoma: pronotal surface finely areolate, laterally with a smooth posterior patch, dorsally with the pronotal disc smooth, and promesonotal dorsum, in lateral view, presenting stiff standing setae. Mesonotal profile slightly sinuous, without a distinctly produced median area, and gradually inclining to the propodeum. Katepisternum strongly areolate with a smooth anteroventral patch. Propodeal projection triangular; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with smoothly rounded side, dorsally smooth, and presenting stiff standing setae. First gastral tergum smooth; dorsally with stiff standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Comments.P. cangussu resembles P. schwarzmaieri Borgmeier. Majors of P. cangussu have the mesosoma surface predominantly smooth, while P. schwarzmaieri has the surface areolate. Minors of P. cangussu have the head smooth and mesosoma finely areolate; P. schwarzmaieri has the head and mesosoma distinctly areolate.

The type-series comes from pitfall traps installed at 804 m in the Parque Estadual do Cerrado, Jaguariaíva, Paraná (see details about the locality at the description of P. abakytan above).

Etymology. From Tupi-Guarani, Old Tupi (see details about the language at the description of P. abakytan above), cang of akánga = head, ussu of uçu = big (de Carvalho, 1987), in apposition, referring to the large head of the major worker.

Pheidole curupira n. sp.

urn:lsid:zoobank.org:act:27A06043-4D88-4B25-AB53-DEE769B54C5A

(Fig. 4, 5, 6, 7, 8, 9, 10, 11)

Holotype major worker: Brazil: PR, Ponta Grossa, P.E. Vila Velha, 25°14'52.74’S 49°59'35.01’W, 19-22.xii.2016 R. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira cols. [CASENT0742949] [DZUP]

Paratype two major and eight minor workers:same data as holotype [DZUP (4 ☿; DZUP549909, DZUP549911, DZUP549910, and CASENT0742950); MCZC (1 ♃ and 2 ☿; DZUP549904, DZUP549907, and DZUP549908); MZSP (1 ♃ and 2 ☿; DZUP549903, DZUP549905, and DZUP549906)]

Cybertypes: holotype, major worker (CASENT0742949) (Supp 7 [online only]) and paratype, minor worker (CASENT0742950) (Supp 8 [online only]), with label transcribed above.

Geographic range. Brazil: Paraná.

Measurements, major worker: EL: 0.13 – 0.16; FL: 0.85 – 0.92; HL: 1.60 – 1.72; HW: 1.36 – 1.52; IHP: 0.20 – 0.25; ML: 1.28 – 1.32; OHP: 0.50 – 0.55, PeL: 0.43 – 0.48; PeW: 0.23 – 0.25; PpL: 0.32 – 0.35; PpW: 0.45 – 0.50; PsL: 0.08; SL: 0.60 – 0.64; CI: 85 – 88; SI: 42 – 44; HPI: 40 – 45 (n = 2).

Major worker. Head: head side, in dorsal view, broadly convex, with standing setae; head dorsal profile forming a smooth, continuous convexity, nearly straight, and vertexal margin moderately emarginate. Hypostoma with median tooth vestigial; inner teeth vestigial, closely spaced. Median clypeal carina vestigial; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, not surpassing superior limit of the eye, with standing setae. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae longitudinally rugulose. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally smooth, anteriorly with transverse, straight to slightly curved rugulae, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile continuous, without a distinctly produced median area, and dropping almost vertically to the propodeum. Katepisternum finely areolate with smooth median patch. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, apically narrow and rounded. Postpetiole, in dorsal view, wider than long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color yellowish-brown.

Measurements, minor worker: EL: 0.10 – 0.13; FL: 0.58 – 0.65; HL: 0.63 – 0.68; HW: 0.55 – 0.60; ML: 0.83 – 0.90; PeL: 0.26 – 0.30; PeW: 0.08 – 0.10; PpL: 0.13 – 0.15; PpW: 0.14 – 0.18; PsL: 0.02 – 0.03; SL: 0.63 – 0.65; CI: 85 – 89; SI: 104 – 114 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface smooth with few piligerous punctures. Mesosoma: pronotal surface finely areolate, laterally with a smooth posterior patch, dorsally with the pronotal disc smooth, and promesonotal dorsum, in lateral view, presenting stiff standing setae. Mesonotal profile slightly sinuous, without a distinctly produced median area, and gradually inclining to the propodeum. Katepisternum strongly areolate. Propodeal projection vestigial; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, trapezoidal, dorsally smooth, and presenting stiff standing setae. First gastral tergum smooth; dorsally with stiff standing setae, no more than 1.5× the eye length. Color yellowish-brown.

Comments.Pheidole curupira resembles P. gigaflavens Wilson, 2003. Majors of P. curupira have the pronotal surface mostly smooth, while P. gigaflavens has this surface areolate. Minors of P. curupira have the head mostly smooth, and P. gigaflavens has the head strongly areolate.

The P. curupira type-series was collected with pitfall traps in the Parque Estadual de Vila Velha, Ponta Grossa, Paraná. The landscape consists of vast extensions of grasslands and shrublands, with small forest enclaves within the Atlantic Forest domain.

Etymology. In apposition, from Brazilian folklore, the curupira has many representations throughout the country, but the common depiction refers to him as a dwarf with red hair, feet in reverse and heels forward so that footprints confound those who are looking for him in the jungle. The name was chosen to honor Brazilian culture, in addition to referring to the small size of this species.

Pheidole idiota rev. stat.

(Fig. 5, 6, 7, 8, 9, 10, 11, 12)

Figure 12
Map of South Brazil showing the localities for the Pheidole species revived here.

Pheidole idiotaSantschi, 1923: 53 (major worker, minor and queen). Lectotype major (CASENT0913471; here designated) and paralectotype minor (CASENT0913472; here designated) worker. Argentina: Córdoba, Alta Gracia. [NHMB] (image examined). Santschi, 1929: 284: subspecies of P. vafra. Wilson, 2003: 244: as junior synonym of P. vafra.

Pheidole vafra idiota maculifrons Santschi, 1929: 53 (major worker, minor and queen). Lectotype major (CASENT0913473; here designated) and paralectotype minor (CASENT0913474; here designated) worker. Argentina: Córdoba, Alta Gracia [NHMB] (image examined). Brown, 1981: 526: as junior synonym of P. vafra idiota and unavailable name, junior homonym of P. maculifrons Wheeler, 1928.

Pheidole laticornis Wilson, 2003: 203 (major and minor worker). Holotype major and paratype minor worker. Costa Rica: Palmar, Puntarenas. [MCZC] (examined). Longino, 2019: 63: as junior synonym of P. vafra. New synonym.

Additional material: 12 ☿: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 804m, 24º10'04.7’S 49º39'59.8’W, 15.i.2015, A.M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos col. [DZUP]; four ☿: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 899m, 24º10'47.6’S 49º40'05.5’W, 15.i.2015, A.M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos col. [DZUP]; three ♃ and 11 ☿: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 917m, 24º11'15.9’S 49º39'53.1’W, 15.i.2015, A.M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos col. [DZUP]; two ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Trilha do Rio, winkler, 24º33'49.61’S 50º15'32.36’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; five ♃ and 14 ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Limpo, 25º14'52.74’S 49º59'5.01’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira col. [DZUP]; six ♃ and four ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Sujo, 25º14'37.85’S 50º00'44.05’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira col. [DZUP]; two ♃ and 18 ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 1 (C. Pastejado), 24º34'7.18’S 50º15'33.72’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; three ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 2 (C. Alto), 24º34'18.36’S 50º15'4.80’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; one ♃ and three ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 3 (Cerrado), 24º33’47.86’S 50º15’14.29’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; two ♃ and one ☿: Brazil: SC, Xanxerê, Oeste, 723m XII.2011-I2-12, 353933.0849 (UTM long) 7031745.381 (UTM lat), M.L.C. Bartz et al cols. [DZUP]; one ♃ and two ☿: Brazil: SC, Chapecó, Oeste, 640m XII.2011-I.2012, 336913.9338 (UTM long) 7002703.673 (UTM lat) M.L.C. Bartz et al cols. [DZUP].

Geographic range. Argentina: Córdoba; Brazil: Paraná and Santa Catarina; and Costa Rica: Palmar.

Measurements, major worker: EL: 0.16 – 0.18; FL: 0.80 – 0.88; HL: 1.04 – 1.08; HW: 0.96 – 1.00; IHP: 0.32 – 0.34 ML: 1.12 – 1.20; OHP: 0.44 – 0.48, PeL: 0.38 – 0.44; PeW: 0.18; PpL: 0.20 – 0.24; PpW:0.23 – 0.24; PsL: 0.08; SL: 0.72 – 0.76; CI: 92 – 93; SI: 72 – 79; HPI: 67 – 77 (n = 3).

Major worker. Head: head side, in dorsal view, broadly convex, with standing setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin deeply emarginate. Hypostoma with median tooth vestigial; inner teeth distinct, narrow and straight, widely spaced. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, and basally terete; with a combination of appressed setae and standing. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally smooth, anteriorly with transverse, straight to slightly curved rugulae, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection triangular. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color dark brown.

Measurements, minor worker: EL: 0.13 – 0.15; FL: 0.55 – 0.63; HL: 0.55 – 0.58; HW: 0.45; ML: 0.73 – 0.83; PeL: 0.25 – 0.28; PeW: 0.08 – 0.10; PpL: 0.13 – 0.15; PpW: 0.12 – 0.13; PsL: 0.04 – 0.05; SL: 0.70 – 0.75; CI: 78 – 82; SI: 156 – 167 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface smooth. Mesosoma: pronotal surface finely areolate, and promesonotal dorsum, in lateral view, presenting stiff standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection triangular; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with straight side, dorsally smooth, and presenting stiff standing setae. First gastral tergum smooth; dorsally with stiff standing setae, no more than 1.5× the eye length. Color dark brown.

Comments.Pheidole idiota can be easily recognized by the basally broad scape which surpasses the midheight between the eyes and the vertexal margin, not reaching the margin. The only morphologically similar species is Pheidole porcula Wheeler. Both species can be distinguished by the gaster pilosity, which in P. idiota the setae have no more than 1.5× the eye length, while in P. porcula the setae are more than 1.5× the eye length. Minors of P. idiota are similar to several species included in the diligens group and the complete description is necessary to distinguish them.

This species has been a junior synonym of Pheidole vafra since Wilson (2003). Wilson (2003) described Pheidole laticornis and considered the scape basally broad of majors as the main diagnostic character of the species. However, P. idiota presents the same character and lacks any significant morphological difference when compared to P. laticornis. In a recent publication, Longino (2019) synonymized P. laticornis under Pheidole vafra, considering the similarity between the images of both types. After examining a large number of specimens, including the sympatric populations of Paraná state (see Franco & Feitosa (2018) for the records), as well the type series and its synonyms, we consider that P. vafra can be securely distinguished from P. idiota by the consistency of the diagnosis above. We revive P. idiota to species with P. laticornis as its junior synonym.

The current disjunct distribution of P. idiota is probably an artifact from the fact that several records for the species in Mesoamerica and southern South America have been attributed to P. laticornis and P. vafra, respectively.

Pheidole mapinguari n. sp.

urn:lsid:zoobank.org:act:4D420C17-B65C-44CC-8C5D-B0371D384941

(Fig. 6, 7, 8, 9, 10, 11)

Holotype major worker: Brazil: PR, Ponta Grossa, P.E. Vila Velha, 25°14'52.74’S 49°59'35.01’W, 24-28.xi.2014 W. Franco, R.M. Feitosa, A.C. Ferreira, F. Benatti cols. [CASENT0742947] [DZUP]

Paratype eight minor workers:same data as holotype [DZUP (2 ☿; DZUP549921 and CASENT0742948); MCZC (3 ☿; DZUP549918, DZUP549919, and DZUP549920); MZSP (3 ☿; DZUP549915, DZUP549916, and DZUP549917)]

Cybertypes: holotype, major worker (CASENT0742947) (Supp 9 [online only]) and paratype, minor worker (CASENT0742948) (Supp 10 [online only]), with label transcribed above.

Additional material: four ♃ and five ☿: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 804m, 24º10'04.7’S 49º39'59.8’W, 15.i.2015, A.M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos col. [DZUP]; five ☿: Brazil: PR, Jaguariaíva, Parque Estadual do Cerrado, 917m, 24º11'15.9’S 49º39'53.1’W, 15.i.2015, A.M. Oliveira, R. Feitosa, J. Maravalhas, H. Vasconcelos col. [DZUP]; five ☿: Brazil: PR, Palmas, R.V.S.C.P. Transecto 2, 26º30'11.05’S 51º40'33.98’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade col. [DZUP]; three ☿: Brazil: PR, Palmas, R.V.S.C.P. Transecto 3, 26º30'38.57’S 51º40'22.40’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade col. [DZUP]; one ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Sujo, 25º14'37.85’S 50º00'44.05’W, 24-28.XI.2014, W. Franco, R.M. Feitosa, A.C. Ferreira, F. Benatti col. [DZUP]; three ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 1 (C. Pastejado), 24º34'7.18’S 50º15'33.72’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; one ♃: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 2 (C. Alto), 24º34'18.36’S 50º15'4.80’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; one ♃ and 26 ☿: Brazil: PR, Tibagi, P.E. do Guartelá, Transecto 3 (Cerrado), 24º33’47.86’S 50º15’14.29’W, 20-25.IX.2015, W. Franco, R.M. Feitosa, A. Machado col. [DZUP]; one ♃: Brazil: RS, Jaquirana, 29º5'43’S 50º22'02’W, Managed Natural Grassland, Traditional Grazing Plot (COM), pitfall trap, XII.2014 [DZUP].

Geographic range. Brazil: Paraná and Rio Grande do Sul.

Measurements, major worker: EL: 0.20; FL: 0.88; HL: 1.12; HW: 1.12; IHP: 0.42; ML: 1.08; OHP: 0.48, PeL: 0.40; PeW: 0.20; PpL: 0.23; PpW: 0.28; PsL: 0.13; SL: 0.84; CI: 100; SI: 75; HPI: 88 (n = 1).

Major worker. Head: head side, in dorsal view, broadly convex, with standing setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin shallowly emarginate. Hypostoma with median tooth vestigial; inner teeth distinct, narrow and slightly curved, converging apically, and widely spaced. Median clypeal carina absent; clypeal disc predominantly smooth, with few rugulae. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, with a combination of appressed setae and standing. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe with interspaces finely areolate. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally finely areolate with humeral area reticulate-rugose, and with few sparse rugulae, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum finely areolate; dorsally with flexuous standing setae, more than 1.5× the eye length. Color reddish-brown.

Measurements, minor worker: EL: 0.15; FL: 0.68 – 0.70; HL: 0.65 – 0.73; HW: 0.60 – 0.63; ML: 0.85 – 0.90; PeL: 0.28; PeW: 0.12 – 0.13; PpL: 0.13 – 0.15; PpW: 0.15 – 0.16; PsL: 0.08; SL: 0.70 – 0.75; CI: 86 – 92; SI: 117 – 125 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, not visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin emarginate; clypeal disc smooth. Space between eye and frontal carina strongly areolate, with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae finely areolate with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface finely areolate. Mesosoma: pronotal surface finely areolate, laterally with a smooth posterior patch, dorsally with few transverse rugulae anteriorly, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with smoothly rounded side, dorsally smooth, and presenting flexuous standing setae. First gastral tergum finely areolate; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color reddish-brown.

Comments.Pheidole mapinguari is similar to P. longiseta Wilson. Majors and minors of P. mapinguari have the pronotal dorsum areolate with few rugulae anteriorly; and P. longiseta has the pronotal dorsum smooth.

This is one of the most common species found in the Parque Estadual de Vila Velha, Ponta Grossa, Paraná. Specimens were mostly collected with pitfall traps in different phytophysiognomies, including open grasslands and shrublands.

Etymology. In apposition, from Brazilian folklore, the mapinguari is a large, black creature, with long hands, clawed nails, and long hair covering its body like a cloak. This name was chosen to honor Brazilian popular culture, in addition to making reference to the dark color and the long gastral pilosity of major workers, with more than 1.5× the eye length.

Pheidole obapara n. sp.

urn:lsid:zoobank.org:act:E51B206A-3F7D-41C8-8295-462D02E0AA50

(Fig. 7, 8, 9, 10, 11)

Holotype major worker: Brazil: PR, Tibagi, P.E. do Guartelá, 24°33'49.61’S 50°15'32.36’W, 20-25.ix.2015 W. Franco, R.M. Feitosa, A. Machado cols. [CASENT0790158] [DZUP]

Paratype one major and three minor workers:same data as holotype [DZUP (2 ☿; DZUP549914 and CASENT0790159); MCZC (1 ♃ and 1 ☿; DZUP549912 and DZUP549913)]

Cybertypes: holotype, major worker (CASENT0790158) (Supp 11 [online only]) and paratype, minor worker (CASENT0790159) (Supp 12 [online only]), with label transcribed above.

Geographic range. Brazil: Paraná.

Measurements, major worker: EL: 0.10; FL: 0.55; HL: 0.95; HW: 0.80 – 0.85; IHP: 0.18 – 0.23; ML: 0.80 – 0.83; OHP: 0.28 – 0.32, PeL: 0.30 – 0.33; PeW: 0.14 – 0.16; PpL: 0.15 – 0.18; PpW: 0.26; PsL: 0.05; SL: 0.38 – 0.40; CI: 84 – 89; SI: 44 – 50; HPI: 56 – 80 (n = 2).

Major worker. Head: head side, in dorsal view, slightly convex, nearly straight, with standing setae; head dorsal profile with a strong convexity just anterior to the vertexal region, and vertexal margin deeply emarginate. Hypostoma with median tooth distinct; inner teeth distinct and broad, in mid-distance from outer teeth. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, not surpassing midheight between eye and vertexal margin, with standing setae. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae with curved rugulae extending from one frontal lobe to another and that gradually become transverse posteriorly, with interspaces finely areolate. Antennal scrobe, in frontal view, shallow and areolate, delimited posteriorly by a curved rugulae. Vertexal surface, in frontal view, transversally rugulose with few reticulate-rugose areas. Mesosoma: pronotum dorsally transversally rugulose, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, without an anterior concavity and with a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, apically narrow and rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Measurements, minor worker: EL: 0.10; FL: 0.40; HL: 0.48 – 0.50; HW: 0.44 – 0.46; ML: 0.58; PeL: 0.20 – 0.22; PeW: 0.08; PpL: 0.10 – 0.12; PpW: 0.10 – 0.12; PsL: 0.02; SL: 0.40 – 0.42; CI: 92 – 115; SI: 87 – 95 (n = 2).

Minor worker. Head: vertexal margin, in dorsal view, emarginate and rounded; occipital carina, in dorsal view, not visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina strongly areolate, with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae strongly areolate with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface strongly areolate. Mesosoma: pronotal surface strongly areolate, and promesonotal dorsum, in lateral view, presenting stiff standing setae. Mesonotal profile continuous, without a distinctly produced median area, and slightly inclining to the propodeum. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, trapezoidal, dorsally smooth, and presenting stiff standing setae. First gastral tergum smooth; dorsally with stiff standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Comments.Pheidole obapara is similar to Pheidole transversostriata Mayr. In both species, majors have curved rugulae in the space between the frontal carinae, which extend from one frontal lobe to the other, becoming gradually transversal posteriorly. Majors of P. obapara have the head dorsal profile anteriorly convex and depressed near the vertexal portion, and the interspaces among the face rugulae areolate; P. transversostriata has the dorsal profile broadly convex, and the interspaces smooth.

Specimens of P. obapara described here were collected in a leaf-litter sample within a small fragment of semideciduous forest beside a stream in the Parque Estadual do Guartelá. See details about the type-locality under the description of P. abaticanga above.

Etymology. From Tupi-Guarani, Old Tupi (see details about the language at the description of P. abakytan above) obá = face, apará = crooked (de Carvalho, 1987), in apposition, referring to the discontinuous dorsal profile of the major worker.

Pheidole obscurior rev. stat.

(Fig. 8, 9, 10, 11, 12)

Pheidole susannae obscurior Forel, 1886: xliv (major and minor worker). Lectotype major (JTLC000015316) and paralectotype minor (JTLC000015317) worker (here designated). Brazil, Rio de Janeiro [MHNG] (image examined). Forel, 1893: 410: queen and male description. Wilson, 2003: 330: raised to species. Longino, 2009: 79: as junior synonym of P. susannae.

Pheidole partita Mayr, 1887: 590 (major worker) 604 (minor worker). Lectotype major (CASENT0916067) worker and paralectotype minor (CASENT0919784) worker (here designated). Brazil: Rio de Janeiro. [NHMW] (image examined). Wilson, 2003: 330: as junior synonym of P. obscurior. Longino, 2009: 79: as junior synonym of P. susannae. New synonym.

Pheidole incisa evoluta Borgmeier, 1929: 204, pl. 6, Fig. 3 (major and minor worker). Lectotype major (CASENT0913456; here designated) and paralectotype minor (CASENT0913457; here designated) worker. Brazil: Rio Grande do Sul, Porto Alegre. [NHMB] (image examined). Kempf, 1964: 63: as junior synonym of P. susannae. New synonym.

Additional material: one ♃ and 10 ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Sujo, 25º14'37.85’S 50º00'44.05’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira col. [DZUP]; one ♃ and five ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Fortaleza, 25º13'7.51’S 50º0'2.08’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira cols. [DZUP]; one ♃: Brasil: PR, Tibagi, P.E. do Guartelá, Transecto 3 (Cerrado), 24°33'47.86S 50°15'14.29W, 20-25.ix.2015, W. Franco, R.M. Feitosa, A.M. Machado cols. [DZUP]; two ☿: Brazil: SC, Lages, Planalto, 859m, Sta GTer. Do Salto, XII.2011-I.2012, 539441.7137 (UTM long) 6925116.989 (UTM lat), M.L.C. Bartz et al. cols [DZUP].

Geographic range. Brazil: Paraná, Rio de Janeiro, Rio Grande do Sul, and Santa Catarina.

Measurements, major worker: EL: 0.20; FL: 1.09 – 1.23; HL: 1.31 – 1.41; HW: 1.50 – 1.56; IHP: 0.40 – 0.43; ML: 1.32 – 1.34; OHP: 0.56 – 0.60, PeL: 0.48 – 0.50; PeW: 0.18 – 0.20; PpL: 0.24 – 0.27; PpW: 0.25 – 0.30; PsL: 0.06 – 0.08; SL: 1.09 – 1.10; CI: 111 – 114; SI: 70 – 73; HPI: 71 (n = 3).

Major worker. Head: head side, in dorsal view, broadly convex, with standing setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin deeply emarginate. Hypostoma with median tooth distinct; inner teeth distinct, narrow and slightly curved, converging apically, and widely spaced. Median clypeal carina absent; clypeal disc predominantly smooth, with few rugulae. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, with a combination of appressed setae and standing. Space between eye and frontal carina reticulate-rugose, with sparse concentric, and a few longitudinal rugulae laterally, and interspaces finely areolate. Space between frontal carinae longitudinally rugulose, with interspaces finely areolate. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally finely areolate with few transverse rugulae, and promesonotal dorsum, in lateral view, presenting a combination of few flexuous standing setae and dense, shorter, thin and apically curved setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin narrowly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum strongly areolate; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light reddish-brown.

Measurements, minor worker: EL: 0.15 – 0.16; FL: 0.76 – 0.85; HL: 0.70 – 0.74; HW: 0.50 – 0.57; ML: 0.90 – 1.05; PeL: 0.30 – 0.33; PeW: 0.10 – 0.11; PpL: 0.14; PpW: 0.16; PsL: 0.05; SL: 0.98 – 1.03; CI: 130 – 140; SI: 139 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc predominantly smooth, with few rugulae. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and interspaces finely areolate. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface finely areolate. Mesosoma: pronotal surface finely areolate, laterally with a smooth posterior patch, and promesonotal dorsum, in lateral view, presenting a combination of few flexuous standing and comparatively longer setae, with dense, shorter, thin and apically curved setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, trapezoidal, dorsally strongly areolate, and presenting flexuous standing setae. First gastral tergum finely areolate; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light reddish-brown.

Comments. Similar species are P. cardinalis Wilson and P. susannae Forel. Majors of P. obscurior have the vertexal surface smooth, while in P. cardinalis it is sculptured. In addition, the pronotal dorsum of P. obscurior is strongly areolate, with few rugulae in majors, and with a combination of few standing flexuous and comparatively longer hairs, with dense, shorter, thin and apically curved hairs; while the pronotal surface of P. susannae is finely areolate in majors, bearing standing hairs only. Finally, sympatric populations between both species are unknown.

In previous studies (Forel 1886; Wilson, 2003), the authors recognized that differences between P. obscurior and P. susannae were mainly related to the color pattern. Longino (2009) synonymized P. obscurior under P. susannae considering that the color pattern is variable in this widespread species. However, P. obscurior presents a very distinct pilosity pattern and pronotal sculpture, which was not recognized by previous authors. The same pilosity pattern and the overall morphology of P. obscurior is shared with P. partita Mayr and P. incisa evoluta Borgmeier. We revive P. obscurior to species with P. partita and P. incisa evoluta as its junior synonyms.

Pheidole paranana rev. stat. et n. stat.

(Fig. 9, 10, 11, 12)

Pheidole triconstricta paranana Santschi, 1925 [1924]: 13 (major worker). Lectotype major (CASENT0913465; here designated) and paralectotype minor (CASENT0913466; here designated) worker. Brazil: Paraná, Rio Negro. [NHMB] (image examined). Wilson, 2003: 221: as junior synonym of P. radoszkowskii.

Additional material: 65 ☿: Brazil: PR, Palmas, R.V.S.C.P. Transecto 1, 26º30'30’S 51º40'8.12’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade col.s [DZUP]; seven ☿: Brazil: PR, Palmas, R.V.S.C.P. Transecto 2, 26º30'11.05’S 51º40'33.98’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade cols. [DZUP]; one ♃ and 24 ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Limpo, 25º14'52.74’S 49º59'5.01’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira col. [DZUP]; 27 ☿: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Sujo, 25º14'37.85’S 50º00'44.05’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira col. [DZUP].

Geographic range. Brazil: Paraná and Santa Catarina.

Measurements, major worker: EL: 0.20; FL: 0,84; HL: 1.15; HW: 1.13; IHP: 0.38; ML: 1.03; OHP: 0.48, PeL: 0.44; PeW: 0.22; PpL: 0.21; PpW: 0.32; PsL: 0.10; SL: 0.88; CI: 98; SI: 78; HPI: 79 (n = 1).

Major worker. Head: head side, in dorsal view, broadly convex, with dense appressed setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin shallowly emarginate. Hypostoma with median tooth vestigial; inner teeth distinct, narrow and slightly curved, converging apically, and widely spaced. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, with appressed setae. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae longitudinally rugulose, with interspaces finely areolate. Vertexal surface, in frontal view, smooth. Mesosoma: pronotum dorsally strongly areolate with a reticulate-rugose area anteriorly, and promesonotal dorsum, in lateral view, presenting sparse appressed setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin narrowly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting stiff standing setae, two longer than the adjacent, and two shorter and appressed. First gastral tergum smooth; dorsally with a combination of stiff standing and appressed setae, no more than 1.5× the eye length. Color reddish-brown.

Measurements, minor worker: EL: 0.14; FL: 0.52 – 0.63; HL: 0.62 – 0.70; HW: 0.54 – 0.62; ML: 0.70 – 0.82; PeL: .29 – 0.33; PeW: 0.08 – 0.10; PpL: 0.13 – 0.14; PpW: 0.116 – 0.19; PsL: 0.05 – 0.06; SL: 0.62 – 0.78; CI: 87 – 89; SI: 115 – 126 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, emarginate and rounded; occipital carina, in dorsal view, not visible; postgenal bridge, in lateral view, areolate. Anterior clypeal margin emarginate; clypeal disc overlain with several rugulae with interspaces areolate. Space between eye and frontal carina strongly areolate, with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae strongly areolate with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface strongly areolate. Mesosoma: pronotal surface strongly areolate, dorsally with a reticulate-rugose patch anteriorly, and promesonotal dorsum, in lateral view, presenting sparse appressed setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection triangular; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, with smoothly rounded side, dorsally smooth, and presenting a combination of a pair of stiff standing setae, with shorter and appressed setae. First gastral tergum smooth; dorsally with a combination of stiff standing and appressed setae, no more than 1.5× the eye length. Color reddish-brown.

Comments. Similar species are P. geraesensis Santschi and P. triconstricta Forel. Majors of P. paranana have the vertexal lobe smooth and the anterior surface of head strongly sculptured with an areolate-rugose patch between eye and frontal carina; and pronotal dorsum areolate with a reticulate-rugose patch anteriorly; P. geraesensis has the head almost entirely smooth; and P. triconstricta has the pronotal dorsum uniformly areolate throughout its distribution in Brazil (Mato Grosso do Sul, Minas Gerais, Paraná, Pernambuco, Rio Grande do Sul, Santa Catarina, São Paulo).

Minors of P. paranana have the clypeal disc overlain with several rugulae with interspaces areolate; P. geraesensis has the surface strongly areolate while in P. triconstricta this surface is smooth. This same key character occurs in sympatric populations of P. paranana and P. triconstricta in the state of Paraná (see Franco & Feitosa (2018) for the records).

This species was first described as a variety of P. triconstricta by Santschi (1925). The author described P. paranana in comparison with P. rosariensis Forel based on the denser head sculpture in P. paranana. The sculpture on the pronotal surface can also readily differentiate these species, while P. paranana has the dorsum reticulate rugose, P. rosariensis has the dorsum areolate. Wilson (2003) synonymized P. paranana under P. radoszkowskii, without further justification. The head sculpture morphologically distinct in both species, with P. radoszkowskii head being densely sculptured and opaque, whereas the fronto-vertexal surface of the head is smooth in P. paranana. We revive P. paranana to species.

Pheidole strobeli rev. stat.

(Fig. 10, 12)

Pheidole strobeli Emery, 1906: 149 (major and minor worker). Goñi, Zolessi & Imai, 1983: 365 (karyotype). Lectotype major (CASENT0904388; here designated) and paralectotype minor (CASENT0904389; here designated) worker. Argentina: Misiones, Posadas. [MSNG] (image examined). Santschi, 1912: 528; Bruch: 1915: 531: subspecies of P. cordiceps. Emery, 1922: 101; Borgmeier, 1927: 61: status as species. Santschi, 1929: 282; Kempf, 1972: 197: subspecies of P. nitidula. Wilson, 2003: 328: as junior synonym of P. nitidula.

Pheidole rufipilis divexa Forel, 1908: 372 (major worker, minor and queen). Lectotype major (CASENT0908118; here designated) and paralectotype minor (CASENT0908203; here designated) worker. Brazil: São Paulo. [MHNG] (image examined). Wilson, 2003: 226: as junior synonym of P. rufipilis. New synonym.

Pheidole nitidula daguerrei Santschi, 1931: 275 (major and minor worker). Lectotype major (CASENT0913358; here designated) and paralectotype minor (CASENT0913359; here designated) worker. Argentina: Buenos Aires, Rosas. [NHMB] (image examined). Wilson, 2003: 328: as junior synonym of P. nitidula. New synonym.

Pheidole perversa Forel, 1908: 373 (major and minor worker). Lectotype major (CASENT0908152) worker and paralectotype minor (CASENT0908153) worker. Brazil: Rio Grande do Sul. [MHNG] (image examined). Emery, 1922: 101: subspecies of P. strobeli. Kempf, 1972: 197: subspecies of P. nitidula. Wilson, 2003: 328: as junior synonym of P. nitidula. New synonym.

Pheidole perversa richteri Forel, 1909: 266 (major and minor worker, and queen). Lectotype major (CASENT0908150; here designated) and paralectotype minor (CASENT0908151; here designated) worker. Argentina, Buenos Aires [MHNG] (image examined). Santschi, 1916: 373: subspecies of P. strobeli. Santschi, 1929: 281: subspecies of P. nitidula. Wilson, 2003: 328: junior synonym of P. nitidula. New synonym.

Pheidole strobeli misera Santschi, 1916: 373 (major worker, minor and queen). Argentina. [probably NHMB] (not examined). Santschi, 1929: 282: as junior synonym of P. strobeli. Wilson, 2003: 328: as junior synonym of P. nitidula. New synonym.

Additional material: 10 ♃: Brazil: PR, Palmas, R.V.S.C.P. Transecto 1, 26º30'30’S 51º40'8.12’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade cols. [DZUP]; 19 ♃ and 74 ☿: Brazil: PR, Palmas, R.V.S.C.P. Transecto 2, 26º30'11.05’S 51º40'33.98’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade cols. [DZUP]; nine ♃: Brazil: PR, Palmas, R.V.S.C.P. Transecto 3, 26º30'38.57’S 51º40'22.40’W, 19-22.XII.2016, R. Feitosa, W. Franco, P. Andrade cols. [DZUP]; one ♃: Brazil: PR, Ponta Grossa, P.E. Vila Velha – Campo Sujo, 25º14'37.85’S 50º00'44.05’W, 19-22.XII.2016, R.M. Feitosa, W. Franco, A.C. Neundorf, Y.S. Moreira cols. [DZUP].

Geographic range. Argentina: Alta Gracia, Buenos Aires, La Plata, and Misiones; and Brazil: Paraná, São Paulo, and Rio Grande do Sul.

Measurements, major worker: EL: 0.17 – 0.20; FL: 0.84 – 0.96; HL: 1.13 – 1.19; HW: 1.09 – 1.16; IHP: 0.33 – 0.37; ML: 1.08 – 1.13; OHP: 0.49 – 0.59, PeL: 0.42 – 0.43; PeW: 0.14 – 0.16; PpL: 0.18 – 0.21; PpW: 0.24 – 0.25; PsL: 0.08 – 0.10; SL: 0.81 – 0.84; CI: 97; SI: 73 – 74; HPI: 57 – 74 (n = 3).

Major worker. Head: head side, in dorsal view, broadly convex, with appressed setae except in the vertexal margin with few standing setae; head dorsal profile forming a broadly, continuous convexity, and vertexal margin shallowly emarginate. Hypostoma with median tooth distinct; inner teeth distinct, narrow and straight, widely spaced. Median clypeal carina absent; clypeal disc smooth. Frontal lobe, in lateral view, projected and rounded. Scape, in frontal view, surpassing midheight between eye and vertexal margin but not reaching the margin, with a combination of appressed setae and standing. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally, and with a reticulate-rugose patch. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface, in frontal view, smooth with few piligerous punctures. Mesosoma: pronotum dorsally smooth, anteriorly with transverse, straight to slightly curved rugulae, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum. Metasoma: petiolar peduncle, in profile, with dorsal margin broadly concave, and petiolar node, in lateral view, broad and apically rounded. Postpetiole, in dorsal view, as wide as long and trapezoidal, and dorsally presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Measurements, minor worker: EL: 0.16; FL: 0.63 – 0.65; HL: 0.66 – 0.70; HW: 0.56 – 0.60; ML: 0.78 – 0.80; PeL: 0.30 – 0.31; PeW: 0.08 – 0.10; PpL: 0.14 – 0.15; PpW: 0.16 – 0.17; PsL: 0.04 – 0.06; SL: 0.72 – 0.74; CI: 85 – 86; SI: 123 – 129 (n = 3).

Minor worker. Head: vertexal margin, in dorsal view, not emarginate and strongly rounded; occipital carina, in dorsal view, visible; postgenal bridge, in lateral view, smooth. Anterior clypeal margin not emarginate; clypeal disc smooth. Space between eye and frontal carina with sparse concentric, and a few longitudinal rugulae laterally. Space between frontal carinae smooth with few longitudinal rugulae extending posteriorly from frontal lobe. Vertexal surface smooth. Mesosoma: pronotal surface smooth, dorsally with few transverse, straight to slightly curved rugulae anteriorly, and promesonotal dorsum, in lateral view, presenting flexuous standing setae. Mesonotal profile sinuous, with an anterior concavity and a distinctly produced median area. Katepisternum strongly areolate. Propodeal projection spiniform, not as long as posterior face of propodeum; and propodeal dorsum finely to strongly areolate. Metasoma: postpetiole, in dorsal view, trapezoidal, dorsally smooth, and presenting flexuous standing setae. First gastral tergum smooth; dorsally with flexuous standing setae, no more than 1.5× the eye length. Color light yellowish-brown.

Comments.Pheidole strobeli resembles Pheidole nitidula Emery and Pheidole dione Forel. Majors of P. strobeli have the lateral margin of head with appressed hairs except in the vertexal margin with standing hairs, while P. dione has standing hairs that extend laterally, and P. nitidula has appressed hairs only. Minors of P. strobeli have the vertexal margin of the head strongly rounded, and mesosoma with stiff standing hairs; P. nitidula has the margin slightly rounded; and P. dione has the mesosoma with flexuous standing hairs.

Pheidole strobeli and P. nitidula occur sympatrically in the state of Paraná (see Franco & Feitosa (2018) for the records), presenting a diagnosis consistent with the described above. Regarding P. dione, only known from Corrientes and Jujuy in Argentina, it is not possible to confirm its sympatry with P. strobeli in a local scale in Argentina, considering that P. strobeli occurs in La Plata and Alta Gracia (Bruch, 1931) as well as Missiones and Buenos Aires (junior synonym distribution).

Based on the head shape and sculpture pattern, this species was considered a subspecies of P. nitidula by Santschi (1929). Later, Wilson (2003) synonymized all the subspecies described for P. nitidula under this name. Pheidole strobeli can be recognized by the distinctly different head pilosity. We revive P. strobeli to species with three of the former subspecies of P. nitidula as its junior synonyms (Pheidole nitidula daguerrei Santschi, 1931, P. perversaForel, 1908, and Pheidole perversa richteri Forel, 1909). Forel (1908) described Pheidole rufipilis divexa, a name subsequently synonymized under Pheidole rufipilis by Wilson (2003). The head sculpture in P. rufipilis (reticulate-rugose extending from the frontal lobe) is notably different from that of P. rufipilis divexa, (only a few rugulae extending from the frontal lobe). We consider P. rufipilis divexa a junior synonym of P. strobeli by the lack of any important morphological differences.

Acknowledgments

Thanks to Aline Oliveira, Ana Carolina Neundorf, Felipe Benatti, Heraldo Vasconcelos, Jonas Maravalhas, Mila Martins, Paloma Andrade, Weslly Franco, and Yohan Moreira for the effort during the field expeditions that provided specimens for this paper and for the DZUP ant collection as well. We are grateful to William Dröse for sending the specimens from Rio Grande do Sul, as well as for UDESC and EMBRAPA colleagues for providing specimens from Santa Catarina and Paraná. The authors thank the OIST imaging section for access to the CT scanner. Leandro Mattos Santos, Jack Longino, John Lattke, Kelli Ramos, Marek Borowiec, and two anonymous reviewers provided valuable comments and suggestions for previous versions of this manuscript. Thanks to the Brazilian Council of Research and Scientific Development (CNPq) for the support provided to ACF (grant 140260/2016-1), RMF (grant 302462/2016-3), and the funding for the project “Ants of the Campos Gerais Paranaenses’ (CNPq grant 459353/2014-4). Thanks to CAPES Foundation for the scholarship grant to ACF (grant PDSE - 88881.189085/2018-01); and the Museum of Comparative Zoology, Harvard University, for the Ernst Mayr Travel Grant that allowed ACF to visit the Ant Room. This paper was partially funded by the Partnerships for Enhanced Engagement in Research (PEER) Science Program (NAS/USAID – award number AID-OAA-A-11-00012 - project 3-188) and by subsidy funding to OIST and JSPS Kakenhi Grant-in-Aid (No. 17K15180).

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• Wilson, E. O., 2003. Pheidole in the New World: a Dominant, Hyperdiverse ant Genus (Vol. 1). Harvard University Press, Cambridge, 818 pp.

Edited by

Associate Editor:

Jeffrey Sosa-Calvo

Publication Dates

• Publication in this collection
  23 Nov 2020
• Date of issue
  2020

History

• Received
  13 July 2020
• Accepted
  20 Sept 2020