Ivieosema Heraty & Burks, 2017

Burks, Roger A., Heraty, John M., Mottern, Jason, Dominguez, Chrysalyn & Heacox, Scott, 2017, Biting the bullet: revisionary notes on the Oraseminae of the Old World (Hymenoptera, Chalcidoidea, Eucharitidae), Journal of Hymenoptera Research 55, pp. 139-188 : 161-163

Ivieosema Heraty & Burks gen. n. Figs 38-43 , 44-48 , 49-54

Type species.

Orasema striatosoma Heraty, 1994: 68-70, figs 98-105.

Etymology.

Named after Michael Ivie of Montana State University; gender feminine.

Discussion.

Defined by Heraty (1994: 68) as the Orasema striatosoma -group. Ivieosema previously contained two mainland African species, which Heraty (1994) noted as being very different from other Orasema . The two new Malagasy species that we include are even more different from other Oraseminae in many ways, but share several features with Ivieosema striatosoma (Heraty), and to a lesser degree with Ivieosema fraudulenta (Reichensperger): a large pit immediately ventral to the median ocellus (Fig. 39 ), continuous striae extending from the axillae to the mesoscutellar disc (Figs 42 , 52 ), propodeal shape and sculpture (Figs 41 , 43 , 52 ), and the laterally sinuate posterior margin of the gastral tergites (Figs 45-46 , 49 ). They differ from the African I. striatosoma and I. fraudulenta in several major ways, including the presence of two additional pairs of depressions between the eye and antennal scrobe, prepectus slightly swollen rather than weakly foveate, lack of any indication of an anterior transverse petiolar carina, and presence of a thickened basal fold in the fore wing. They also exhibit further reductions in surface sculpture, mouthparts and wing setation. All of the species have a closely appressed pronotum and prepectus that appear fused in the Malagasy species, a nearly quadrate anellus, and a thickened marginal vein. Notably the anterior margin of the fore wing beyond the stigmal vein is rounded similar to that of Cymosema .

Diagnosis.

Separated from other Oraseminae by the deep sharply impressed pit just below the median ocellus (Fig. 39 ). Distinguished from other Old World genera by the head subtriangular in frontal view (Figs 39 , 50 ); scrobal depression below pit broadly impressed, lacking parallel channels or dorsal scrobal foveae; dorsal occipital margin abrupt and rounded; funicle 7-segmented; labrum with 4-digits; mesonotum appearing bare, at most with minute setae; mesoscutal lateral lobes and frenum finely sculptured; transscutal articulation complete or fused medially; propodeal disc evenly and finely sculptured (Figs 43 , 52 ); prepectus with upper panel broad and flat, at most with a slightly raised posterior margin, very tightly appressed to posterior margin of pronotum (Figs 41 , 52 ); fore wing with basal area pilose or bare (Figs 44 , 55 ), wing disc with dense long setae (African species) or lacking setae but with sockets apparent (Malagasy species); marginal vein thickened along entire length; postmarginal vein absent or not much longer than stigmal vein; petiole base narrowed into foramen and lacking basal flange (Figs 45 , 52 ); antecostal sulcus present and smooth; posterior lateral margin of gastral tergites 1-4 sinuate; first valvula of ovipositor with several fine lateral teeth. Male scape lacking ventral pores.

Host association.

Myrmicinae : Ivieosema fraudulenta reared from Pheidole megacephala Fabricius ( Reichensperger 1913).

Distribution.

Ethiopian and Malagasy regions.

Figures

Figure 55. Ivieosema limula. Holotype female: fore wing.

Figures 38 - 43. Ivieosema confluens. Paratype female: 38 head and mesosoma, lateral 39 head, anterior 40 antenna, medial 41 mesosoma, lateral 42 mesosoma, dorsal 43 mesosoma, posterior. dfd = dorsal frontal depression; F 1 / an = anellus; lg = longitudinal groove; sod = subocellar depression; tsa = transscutal articulation.

Figures 44 - 48. Ivieosema confluens. Paratype female: 44 fore wing 45 metasoma, lateral, lateral view of ovipositor in top left corner. Holotype male: 46 habitus, lateral 47 head, anterior 48 antennae, dorsal. dv = dorsal (2 nd) valvula, F 1 / an = anellus; vv = ventral (1 st) valvula.

Figures 49 - 54. Ivieosema limula. Holotype female: 49 habitus, lateral 50 head, anterior 51 antenna, lateral 52 mesosoma, lateral 53 mesosoma, dorsal 54 ovipositor, lateral. dfd = dorsal frontal depression; F 1 / an = anellus; lg = longitudinal groove; mts = metascutellum; tsa = transscutal articulation.