Megalopodidae (Insecta, Coleoptera): new occurrence and host plant records for Brazil

Abstract

The Brazilian Megalopodidae fauna consists of 147 species from 11 genera, of which Mastostethus Lacordaire is the most diverse, representing about half of the species. Nevertheless, knowledge about species distributions and their relationships with host plants is still scarce. Since this group has endophytic immatures and bore into branches, they are economically important as they mainly damage Solanaceae species. Thus, this study sought to determine the Megalopodidae species that occur in forest fragments of southwestern and western Paraná and associate them with their host plants. For this purpose, we used material collected with Malaise traps and active manual sampling to determine associations with host plants. A total of 170 specimens of 11 species were sampled, of which Pseudhomalopterus carinatus Pic, 1920 was the most abundant and collected in all fragments. Four species were sampled exclusively through manual collections and associated with their host plants, all of which were new association records for Brazilian megalopodides. Mastostethus pantherinus Lacordaire, 1845 was associated with an Asteraceae for the first time. Additionally, Mastostethus minutusMonrós, 1947 is a new record for Brazil.

Keywords.
Biodiversity survey; Solanaceae; Asteraceae; Megalopodinae; New occurrence

INTRODUCTION

Megalopodidae (Coleoptera) has just over 600 species allocated in 30 genera belonging to the subfamilies Megalopodinae, Palophaginae and Zeugophorinae (Erber & Medvedev, 2002; Rodríguez-Mirón, 2018). Megalopodinae contains about 80% of the species, presenting the highest diversity in the Ethiopian and Neotropical regions (Rodríguez-Mirón, 2018). In Brazil, 147 species belonging to 10 genera have been recorded, and Mastostethus Lacordaire, 1845 is the most diverse genus with 79 species (Botero, 2018).

Megalopodidae are associated with a wide variety of host plants, including families as Solanaceae, Asteraceae, Euphorbiaceae, Oleaceae, and Fabaceae (Jolivet, 1988; Lawrence & Slipinski, 2014). Despite this, host plants are known for few species, and in South America, Megalopodinae are most associated with Solanaceae (Rodríguez-Mirón, 2018). This group is economically important because its members are phytophagous with endophytic larvae that feed on internal tissues of branches and stems (Lawrence & Slipinski, 2014). For example, some studies consider Agathomerus (Euagathomerus) sellatus (Germar, 1823) and A. (Agathomeroides) flavomaculatus (Klug, 1845) as secondary pests of tomatoes, scarlet eggplant, and peppers, mainly damaging leaves, stems, and shoots (Tella, 1952; Lima, 1955; Vernalha et al., 1968; Santos, 1981; Picanço et al., 1999; Almeida et al., 2009; Modolon et al., 2013).

Thus far, information about Megalopodidae fauna in Brazil has been scarce, both in terms of species diversity, distribution, and relationships to host plants and bioecological information. Given the lack of research about this taxon, the groups’ potential economic interest due to the damage it causes to Solanaceae plants and considering there are no records of this group in southwestern Paraná, this work is important because it provides new information about Megalopodidae fauna in a region that has been suffering greatly from anthropic pressures. Thus, the aim of this study was to record the Megalopodidae species that occur in forest fragments in southwestern and western Paraná, seeking to associate them with their host plants.

MATERIAL AND METHODS

The material was collected from four forest fragments, three of which were found in southwestern Paraná, in the municipalities of Planalto, Realeza and Santa Izabel do Oeste and one in Céu Azul in western Paraná. The forest fragments are located in Montane and Submontane Mixed Ombrophilous phytogeographic formation. However, the Céu Azul fragment is in Montane Semideciduous Seasonal Forest phytogeographic formation (ITCG, 2009). More information about these fragments can be found in Rech & Linzmeier (2019).

Two Malaise traps (Townes, 1972) were installed in each fragment, except for the Santa Izabel do Oeste fragment, where only one trap was installed. Weekly samples were carried out from October 2016 to March 2017 (Realeza, Planalto, and Sta Izabel do Oeste) and from September 2017 to March 2018 (Realeza, Planalto, and Céu Azul).

In order to identify host plants, manual samplings were carried out in the Planalto fragment weekly from September to December 2017. Plants were inspected for megalopodides, and when found, they were observed, photographed, and collected. Plant parts (flowers, stems, and leaves) were photographed and collected to make exsiccates (Fidalgo & Bononi, 1989). Insect-plant associations were only considered when the megalopodid was observed feeding on some plant parts. All observations were made in the field.

For Megalopodinae identification, the Monrós identification key (1947) was used. Also was carried out by means of the comparison with reference material and in some cases with the type specimen of the species deposited in: The Natural History Museum, London, U.K., National Museum of Natural History, Smithsonian Institution, Washington, D.C. USA, and Muséum National d’Histoire Naturelle, Paris, France. The plants were identified using the Herbário Virtual - REFLORA, Flora do Brasil 2020 (REFLORA, 2020) and Flora Digital (Giehl, 2020). The insects are deposited in the Coleção Entomologica UFFS-RE at Universidade Federal da Fronteira Sul, Campus Realeza, PR, and the exsiccates in the Herbário REAL at the same institution.

RESULTS AND DISCUSSION

In total, 170 Megalopodidae specimens belonging to 11 species of the genera Mastostethus Lacordaire, 1845, Agathomerus Lacordaire, 1845, Megalopus Fabricius, 1801 and Pseudhomalopterus Pic, 1920 were collected, with Mastostethus presenting the highest richness: five species (Table 1, Fig. 1). The most abundant species was Pseudhomalopterus carinatus Pic, 1920, with 78 specimens, followed by Mastostethus lateritius (Klug, 1834) with 31 specimens, both sampled in all fragments, and Megalopus tabidus Klug, 1834 with 26 individuals. The remaining species were less abundant and did not exceed nine individuals (Table 1).

Figure 1
Species of Megalopodinae (Megalopodidae) sampled from forest fragments in southwestern and western Paraná. (A) Mastostethus sobrinus Lacordaire, 1845; (B) Mastostethus pantherinus Lacordaire, 1845; (C) Mastostethus lateritius (Klug, 1834); (D) Mastostethus alternans (Klug, 1834); (E) Mastostethus minutusMonrós, 1947; (F) Megalopus tabidus Klug, 1834; (G) Megalopus waterhousei Baly, 1859; (H) Agathomerus (Euagathomerus) sellatus (Germar, 1823); (I) Agathomerus (Euagathomerus) elegans (Klug, 1834); (J) Agathomerus (Agathomeroides) flavomaculatus (Klug, 1845); (K) Pseudhomalopterus carinatus Pic, 1920.

Table 1
Species of Megalopodinae (Megalopodidae) collected from forest fragments in southwestern and western Paraná and their abundance in each sampled forest fragment. Note: *species collected with Malaise; ** manually sampled species.

Species	Planalto (N)	Realeza (N)	Céu Azul (N)	Santa Izabel do Oeste (N)	Total
Agathomerus (Agathomeroides) flavomaculatus (Klug, 1845)**	5	-	-	-	5
Agathomerus (Euagathomerus) elegans (Klug, 1834)**	5	-	-	-	5
Agathomerus (Euagathomerus) sellatus (Germar, 1823)**	2	-	-	-	2
Pseudhomalopterus carinatus Pic, 1920*	15	44	15	4	78
Mastostethus alternans (Klug, 1834)*	-	1	-	1	2
Mastostethus minutus Monrós, 1947 *	1	-	1	1	3
Mastostethus pantherinus Lacordaire, 1845**	1	-	-	-	1
Mastostethus lateritius (Klug, 1834)*	11	14	5	1	31
Mastostethus sobrinus Lacordaire, 1845*	5	-	4	-	9
Megalopus tabidus Klug, 1834*	8	-	18	-	26
Megalopus waterhousei Baly, 1859*	1	-	6	1	8
Total	54	59	49	8	170

All genera collected are exclusively Neotropical. The genera Mastostethus, Agathomerus, and Megalopus are widely distributed from Argentina to Mexico (Rodríguez-Mirón et al., 2017; Rodríguez-Mirón, 2018). For Brazil, Mastostethus is the genus with the highest number of species, with 79 registered names, followed by Agathomerus with 33 species and Megalopus with 26 species (Botero, 2018). Pseudhomalopterus is a monotypic genus only registered in this country (Botero, 2018; Rodríguez-Mirón, 2018). Except for the Agathomerus species and M. pantherinus Lacordaire, 1845, all species recognized in this study are new records to the state of Paraná. Mastostethus minutusMonrós, 1947, previously known only to Argentina, is also a new record to Brazil, increasing the number of Brazilian Megalopodidae species to 148.

Seven species were exclusively sampled with malaise traps and four species through manual collections (Table 1). Thus, none of the species sampled with Malaise were observed in the field, and although those species were most abundant and occurred in all fragments, it was not possible to determine their host plants. However, for the first time, more precise distribution data is provided for these species.

Adults of Agathomerus (A.) flavomaculatus (Fig. 2C) and Agathomerus (E.) elegans (Klug, 1834) (Fig. 2A) were observed feeding on Solanum (cf., Solanum variabile Mart.) (Solanaceae) flowers. According to Lima (1955), the larvae of A. (A.) flavomaculatus drill holes in the stem bases and adults feed on leaves and flowers. Additionally, A. (A.) flavomaculatus was one of the most abundant species associated with the scarlet eggplant plant (Solanum gilo Raddi) where its larvae were found boring into the branch bases (Picanço et al., 1999). This species is widely distributed in Brazil and has been recorded in the states of Goiás, Minas Gerais, Espírito Santo, Rio de Janeiro, and from São Paulo to Rio Grande do Sul, in addition to Paraguay and Argentina (Carvalho & Monné, 2006).

Figure 2
Species of Megalopodinae (Megalopodidae) on its host plants, registered in southwestern Paraná. (A) Agathomerus (E.) elegans feeding on Solanum (cf., S. variabile) (Solanaceae); (B) Mastostethus pantherinus feeding on Vernonanthura (cf., V. tweediena) (Asteraceae); (C) Agathomerus (A.) flavomaculatus feeding on Solanum (cf., S. variabile) (Solanaceae); (D) Agathomerus (E.) sellatus feeding on Solanum betaceum (Solanaceae).

Adults of Agathomerus (Eugathomerus) sellatus were recorded feeding on Solanum betaceum Cav. (Solanaceae) (Fig. 2D). The adults fed abaxially on the petiole, at the base of leaves that had withered. Inside the branch where the plant was damaged, there was a single white egg. Similar observations were made by Tella (1952) and Santos (1981), who reported aspects of this species’ biology in tomatoes (Lycopersicum esculentum Mill.). Such association with tomato has been reported by several authors (Table 2) and, although A. (E.) sellatus has not yet been reported as a regular pest of tomato crops, it has frequently been found on conventional crops and is considered an emerging pest (Bavaresco & Pilati, 2005). Agathomerus (E.) sellatus has also been recorded damaging potato (Solanum tuberosum L.), eggplant (Solanum melongena L.), and chayote (Sechium edule S.) (Tella, 1952; Vernalha et al., 1968). However, in Vernalha et al.’s (1968) paper the image illustrating the species (on page 116) is not actually Agathomerus sellatus, but Cacoselis sp. (Chrysomelidae, Galerucinae, Alticini), a genus associated with passion fruit (Lima, 1955).

Table 2
Records of host plants for Megalopodidae that occur in Brazil, available in the literature and registered in this study.

Megalopodidae species	Host plant	Associated family plant	References
Agathomerus sp.	Adenostemma sp.	Asteraceae	Jolivet, 1988
Agathomerus (E.) sellatus	Lycopersicum esculentum	Solanaceae	Tella, 1952
			Modolon et al., 2013
			Bavaresco & Pilati, 2005
			Vernalha et al., 1968
			Jolivet, 1977
	Solanum melongena	Solanaceae	Vernalha et al., 1968
	Solanum tuberosum L.	Solanacea	Tella, 1952
			Vernalha et al., 1968
	Sechium edule S.	Cucurbitaceae	Vernalha et al., 1968
	Solanum sp. (juá)	Solanaceae	Silva et al., 1968
	Solanum betaceum	Solanaceae	In this study
Agathomerus (A.) flavomaculatus	Alternanthera sp.	Amaranthaceae	Lima, 1955
	Capsicum baccatum L.	Solanaceae	Carvalho & Moné, 2006
			Jolivet, 1977
	Solanum gilo R	Solanaceae	Picanço et al., 1999
	Solanum (cf., S. variabile)	Solanaceae	In this study
Agathomerus (E.) elegans	Solanum (cf., S. variabile)	Solanaceae	In this study
Mastostethus spp.	Alternanthera sp.	Amaranthaceae	Lawrence & Slipinski, 2014
		Bignoniaceae	Jolivet, 1988
		Verbenaceae
		Euphorbiaceae
Mastosthethus pantherinus	Vernonanthura (cf., V. tweediena	Asteraceae	In this study
	Solanum (cf., S. variabile)	Solanaceae	In this study
Megalopus sp.	S. andigenum	Solanaceae	Jolivet, 1977
	S. tuberosum
	S. lycopersicum

Mastostethus pantherinus Lacordaire, 1845 was observed in Vernonanthura, (cf., Vernonanthura tweediena ((Baker) H. Rob. (Asteraceae)) (Fig. 2B). The captured specimen was found consuming the stem base. This species was also found feeding on the flowers of the same species of Solanum sp. registered for A. (A.) flavomaculatus. There are records of Mastostethus in plants of the families Bignoniaceae, Verbenaceae, Euphorbiaceae, and Amaranthaceae (Jolivet, 1988; Lawrence & Slipinski, 2014). In Brazil, there are no records of host plants for this species. Thus, herein we present records of two new host plants for M. pantherinus, along with its association with Asteraceae for the first time.

Considering the records of host plants for Brazilian megalopodides (Table 2), it is possible to affirm that all host plant associations observed in this study are new records for the species.

Thus, it was possible to recognize eleven species in four genera of Megalopodidae that occur in the southwestern and western regions of Paraná, one of which is a new record for Brazil - Mastostethus minutus. In addition, we found new Megalopodinae associations with host plants, demonstrating that there is still much to be investigated, with Asteraceae being recorded for the first time for Mastostethus in Brazil. Finally, the results herein not only increase knowledge about Megalopodidae species from southwestern and western Paraná State, but also for Brazil.

REFERENCES

• Almeida, D.G.; Andrade, S.G. Viventini, B.V.; Barbosa, F.W.; Sobreira, M.F. & Pratissoli, D. 2009. Occurrence of Faustinus sp. (Coleoptera: Curculionidae) in Southeastern Brazil tomato crops. Agronomia Colombiana, 27(3): 417-419.
• Bavaresco, A. & Pilati, G. 2005. Ocorrência de Agathomerus sellatus em tomateiro no Planalto Norte Catarinense. Agropecuária Catarinense, 18: 95-97.
• Botero, J.P. 2018. Megalopodidae. In: Catálogo taxonômico da fauna do Brasil Available: Available: http://fauna.jbrj.gov.br/fauna/faunadobrasil/124836 Access: 09/09/2020.
  » http://fauna.jbrj.gov.br/fauna/faunadobrasil/124836
• Carvalho, E.B. & Monné, M.L. 2006. Agathomerus (Agathomeroides) flavomaculatus (Coleoptera, Megalopodidae, Megalopodinae): morfologia da larva e do adulto. Iheringia , Série Zoologia, 96(3): 329-334.
• Erber, D. & Medvedev, L.N. 2002. Untersuchungen zur Taxonomie afrikanischer Megalopodinae mit Beschreibungen einer neuen Gattung und fünf neuer Arten (Coleoptera, Chrysomelidae). Entomologica Basiliensia, 24: 97-121.
• Fidalgo, O. & Bononi, V.L. 1989. Técnicas de coleta, preservação e herborização de material botânico São Paulo,: Instituto de Botânica. 62p.
• Giehl, E.L.H. 2020. Flora digital do Rio Grande do Sul e de Santa Catarina Available: Available: https://floradigital.ufsc.br Access: 09/09/2020.
  » https://floradigital.ufsc.br
• Instituto de Terras, Cartografia e Geociências (ITCG). 2009. Formações fitogeográficas do estado do Paraná Mapa fitogeográfico, escala 1:2.000.000
• Jolivet, P. 1977. Trophique selection in Eupoda (Coleoptera: Chrysomelidae): Megalopodinae. Bulletin Mensuel de la Société Linnéenne de Lyon, 46(9): 321-336.
• Jolivet, P. 1988. Food habitats and food selection of Chrysomelidae. In: Jolivet, P.; Petitpierre, E. & Hsiao, T.H. (Eds.). Biology of Chrysomelidae Dordrecht, Kluwer Academy Publishers. p. 1-24.
• Lawrence, J.F. & Slipinski, A. 2014. Megalopodidae Latreille, 1802. In: Leschen. R.A.B. & Beutel, R.G. (Eds.). Coleoptera, beetles. Morphology and systematics (Phytophaga). Handbook of Zoology Berlin, Walter de Gruyter GmbH. p. 178-183.
• Lima, C.A. 1955. Insetos do Brasil Coleópteros.. Rio de Janeiro, Escola Nacional de Agronomia. 9º tomo, 3ª parte. 289p.
• Modolon, T.A.; Boff, P.; Boff, M.I.C.; Gonçalves, P.A.S. & Miquelluti, D.J. 2013. Ocorrência de insetos em plantas de tomateiro tratadas com preparados em altas diluições. Revista de Ciências Agroveterinárias, 12(2): 155-162.
• Monrós, F. 1947. Revisión de los Megalopodidae Argentinos (Col., Chrysomeloidea). Revista de la Sociedad Entomológica Argentina, 13: 150-217.
• Picanço, M.; Leite, G.L.D.; Bastos, C.S.; Suinaga, F.A. & Casali, V.W.D. 1999. Coleópteros associados ao jiloeiro (Solanum gilo Raddi). Revista Brasileira de Entomologia, 43(1/2): 131-157.
• Rech, T. & Linzmeier, A.M. 2019. Assembleia de Alticini (Coleoptera, Chrysomelidae, Galerucinae) em fragmentos florestais no sudoeste do Paraná, Brasil. Iheringia , Série Zoologia, 109: 1-9. http://doi.org/10.1590/1678-4766e2019024
  » http://doi.org/10.1590/1678-4766e2019024
• REFLORA - Plantas do Brasil: Resgate Histórico e Herbário Virtual para o Conhecimento e Conservação da Flora Brasileira. 2020. Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, COPPETEC - UFRJ. Available: Available: http://floradobrasil.jbrj.gov.br/reflora/PrincipalUC/PrincipalUC.do Access: 09/09/2020.
  » http://floradobrasil.jbrj.gov.br/reflora/PrincipalUC/PrincipalUC.do
• Rodríguez-Mirón, G.M. 2018. Checklist of the family Megalopodidae Latreille (Coleoptera: Chrysomeloidea): a synthesis of its diversity and distribution. Zootaxa, 4434(2): 265-302. http://doi.org/10.11646/zootaxa.4434.2.3
  » http://doi.org/10.11646/zootaxa.4434.2.3
• Rodríguez-Mirón, G.M.; Zaragoza-Caballero, S. & López-Pérez, S. 2017. Comparative morphology of the spermatheca in Megalopodidae (Coleoptera, Chrysomeloidea). ZooKeys, 720: 47-64. http://doi.org/10.3897/zookeys.720.14088
  » http://doi.org/10.3897/zookeys.720.14088
• Santos, H.R. 1981. Biologia de Agathomerus sellatus (Germar, 1824) (Coleoptera, Chrysomelidae, Megalopodinae) broca do tomateiro. Revista Brasileira de Entomologia, 25(2): 165-170.
• Silva, A.G.E.; Gonçalves, C.R.; Galvão, D.M.; Gonçalves, A.J.L.; Gomes, J.; Silva, M.N. & Simoni, L. 1968. Quarto catálogo dos insetos que vivem nas plantas do Brasil, seus parasitas e predadores Rio de Janeiro, Ministério da Agricultura, Departamento de Defesa e Inspeção Agropecuária. parte 2, tomo 1.
• Tella, R. 1952. Contribuição para o conhecimento do Agathomerus sellatus Germ. (Col., Megalopodidae). Revista da Agricultura, 27: 373-376.
• Townes, H. 1972. A light-weight malaise trap. Entomological News, 83(9): 239-247.
• Vernalha, M.M.; Rocha, M.A.L.; Gabardo, J.C. & Silva, R.P. 1968. Principais pragas das plantas cultivadas no Estado do Paraná Curitiba, Diretório Acadêmico Lycio Vellozo. 264p.

• Published with the financial support of the "Programa de Apoio às Publicações Científicas Periódicas da USP"

Edited by

Edited by: Simone Policena Rosa

Publication Dates

• Publication in this collection
  08 Dec 2021
• Date of issue
  2021

History

• Received
  09 Mar 2021
• Accepted
  10 Sept 2021
• Published
  27 Oct 2021