Two new species of Emersonella ( Hymenoptera : Eulophidae : Entedoninae ) from the Brazilian Atlantic Forest

Emersonella Girault, 1916 is a wasp genus including species that parasitize Chrysomelidae (Coleoptera) eggs, mainly Cassidinae. It occurs only in the Americas, and is primarily distributed in the Neotropical Region. In this paper two new species of Emersonella from the Atlantic Forest of southeastern Brazil are described and compared to similar species. Emersonella appendigaster sp. nov. is characterized by an elongate last gastral tergite in female, thoracic dorsum flat, femora and tibiae yellowish in female, malar sulcus absent, frontal suture slightly down-curved laterally, eyes with scattered hairs, frons and vertex smooth, and propodeum smooth with small anteromedian foveae. Emersonella frieirocostai sp. nov. is characterized by an elongate gaster in the female, at most 1.3 times as long as mesosoma and pointed at apex, propodeum with two large anterolateral foveae, pronotum hardly visible in dorsal view, with posterior part smooth, transverse pronotal carina present and malar sulcus absent. Both species are egg parasitoids of Metriona elatior (Klug, 1820) (Chrysomelidae) which feeds on Solanum viarum Dunal (Solanaceae).

Most species of Eulophidae parasitize phytophagous hosts (LASALLE 2005).This is also true of Emersonella Girault, 1916, a genus that occurs only in the Americas, and which is primarily distributed in the Neotropical Region (HANSSON 2002).Only two species, E. lemae Girault, 1916 andE. niveipes Girault, 1917 are known from the Nearctic Region.
The Neotropical Emersonella were revised by HANSSON (2002) and DE SANTIS (1983).Initially, DE SANTIS (1983) studied the Argentinian, Uruguayan, and Brazilian species, and proposed two generic names as junior synonyms of Emersonella: Pleurotropitiella Blanchard, 1945and Testudicida De Santis, 1949. Subsequently, HANSSON (2002) studied 55 Costa Rican species, of which 47 were described as new, and presented many records from other countries in the Neotropical Region.Later, HANSSON & NISHIDA (2004) described another new species from Costa Rica.
Solanum viarum is native to South America, occurring in Brazil, Paraguay, and Argentina (MEDAL et al. 1996, 1999, ROSSINI et al. 2002).Introduced and adapted populations have been recorded from India, Nepal, Mexico, Greater and Lesser Antilles, Africa, Burma (Myanmar), Honduras, West Indies, and southeastern United States (USDA 2010).An alien species, S. viarum is considered a noxious plant.It infests pastures, cultivated, and natural areas (MEDAL et al. 1996, USDA 2010).Studies suggest that biological control is the best alternative to suppress this plant (MEDAL et al. 1996, ROSSINI et al. 2002).Due to its dietary specialization, the cassidine beetle M. elatior is a putative candidate for the biological control of S. viarum in areas where it is not native (MEDAL et al. 1999, AL GAZI et al. 2008).Natural enemies of M. elatior were not known prior to the present work.This information is important to future research on the population regulation of S. viarum and M. elatior.Diagnosis.Last gastral tergite in female elongate (more than three times as long as width at base); thoracic dorsum flat; femora and tibiae in female yellowish; malar sulcus absent; frontal suture slightly down-curved laterally (Fig. 1); eyes with scattered hairs; without a small spine above base of forecoxae; frons and vertex smooth (Figs. 1 and 2); propodeum smooth with small (compared to the other species treated here) anteromedian foveae (Fig. 4).

MATERIAL AND METHODS
Description.Female.Length of body (excluding 7th tergite) 1.0-1.3mm.Scape yellowish-white, remainder of antenna dark.Frons bluish-green and vertex with golden tinges.Mesoscutum and scutellum dark purple.Propodeum metallic blue with golden tinges.Coxae dark and metallic; femora and tibiae yellowish; tarsi yellowish-white with 4th segment brown.Wings hyaline.Petiole dark purple.Female with first gastral tergite golden-green, remaining tergites golden-purple.Antenna as in Fig. 5. Frons and vertex smooth and shiny; frontal suture slightly down-curved laterally.Malar sulcus absent.Occipital margin with a sharp edge (Fig. 2).Eyes with scattered hairs.Ratios of height of head/width of head 1.2, height of eye/malar space/width of mouth opening 2.2/1.0/1.6,distances between posterior ocelli/between posterior ocellus and eye/between posterior ocelli and occipital margin 5.7/3.1/1.0,width of head/ width of thorax across shoulders 1.3.Thoracic dorsum flat.Transverse pronotal carina present.Without a spine above base of forecoxa.With a groove separating mesoscutum from scutellum.Mesoscutum with strong large meshed reticulation; notauli narrow, indicated in anterior one-third.Scutellum with raised reticulation (Fig. 3).Dorsellum flat and smooth.Forewing speculum closed below; with nine admarginal setae.Propodeum with two transverse foveae anterolaterally, with a large anteromedian fovea, propodeal callus with two setae.Petiolar foramen rounded.Ratios: length of forewing/length of marginal vein/ height of forewing 1.6/1.1/1.0;length of postmarginal vein/ length of stigmal vein 0.2.Petiole transverse.Female gaster elongate with last tergite and ovipositor sheaths protruding, last tergite 3.0 times as long as width at base.Ratio of length of mesosoma/length of gaster 0.9.
Male.Length of body 1.2 mm.Male with scape yellowish-brown, darker along dorsal edge; Femora dark brown; gaster, in dorsal view, with a whitish spot on the first half.Ratio of length of mesosoma/length of gaster 1.0.
Remarks.Only three additional species of Emersonella have the last gastral tergite elongated in the female (more than 3.0 times as long as width at base): Emersonella hastata Hansson, 2002, E. metallica Hansson, 2002, and E. terebrata Hansson, 2002.Emersonella appendigaster sp.nov.differs from E. hastata and E. metallica in having the thoracic dorsum flat, anterolateral foveae on propodeum, malar sulcus absent.Additionally, the female of E. appendigaster has femora and tibiae yellowish.Furthermore, E. appendigaster also differs from E. metallica in having the frontal suture slightly down-curved laterally and eyes with scattered hairs.It differs from E. terebrata in having the frons, vertex, and propodeum smooth, and without a small spine above base of forecoxae.
The female differs from the male mainly by the insertion of the petiole at the top of the gaster (Figs. 6 and 7).Also, the male does not have the last gastral tergite elongated.Male with dark femora and a pale spot on gaster.
Etymology.Name given in reference to the shape and arrangement of the female gaster (Fig. 6).

Two new species of Emersonella (Hymenoptera: Eulophidae: Entedoninae) from the Brazilian Atlantic Forest Thiago M. Alvarenga 1,4 , Valmir A. Costa 2 , Christer Hansson 3 & César F. Carvalho 1 ABSTRACT
. Emersonella Girault, 1916 is a wasp genus including species that parasitize Chrysomelidae (Coleoptera) eggs, mainly Cassidinae.It occurs only in the Americas, and is primarily distributed in the Neotropical Region.In this paper two new species of Emersonella from the Atlantic Forest of southeastern Brazil are described and compared to similar species.Emersonella appendigaster sp.nov. is characterized by an elongate last gastral tergite in female, thoracic dorsum flat, femora and tibiae yellowish in female, malar sulcus absent, frontal suture slightly down-curved laterally, eyes with scattered hairs, frons and vertex smooth, and propodeum smooth with small anteromedian foveae.Emersonella frieirocostai sp.nov. is characterized by an elongate gaster in the female, at most 1.3 times as long as mesosoma and pointed at apex, propodeum with two large anterolateral foveae, pronotum hardly visible in dorsal view, with posterior part smooth, transverse pronotal carina present and malar sulcus absent.Both species are egg parasitoids of Metriona elatior (Klug, 1820) (Chrysomelidae) which feeds on Solanum viarum Dunal (Solanaceae).KEY WORDS.Cassidinae; eggs; endoparasitoids; host specificity; Solanaceae.ZOOLOGIA 32 (2): 145-150, April 2015