Orasema lasallei, 1884

Heraty, John M. & Baker, Austin J., 2020, New species of Orasema (Hymenoptera: Eucharitidae) from Central and South America, Journal of Natural History 54 (9), pp. 735-754 : 737

Orasema lasallei species group

Diagnosis

Recognised from all other species of Orasema by having a combination of 8 funiculars in males and females ( Figure 2 ), the labrum with 4 – 12 digits (usually>6), mesothorax dorsally scabrous or coarse rugose, fore wing with a setose costal cell, speculum bare, and basal third of hind wing with scattered microsetae, otherwise pilose. Other features include the yellow scape, yellowish-brown mandibles with a darker brown margin, propodeal callus with 2 – 3 minute setae, wings hyaline, postmarginal vein not more than 2.3× as long as stigmal vein, fore wing with basal area bare, petiole cylindrical and rugose, lateral margins of petiole rounded (not carinate), 2.1 – 3.8× as long as broad in females, 8.3 – 10× as long as broad in males, and smooth antecostal sulcus.

Key

In the Burks et al. (2018) species group key, this species group keys to ‘ [undescribed set of Neotropical species] ’ in the Orasema festiva couplet with more than 6 digits, although we now recognise that some specimens have as few as 4 digits. All festiva group species have a lateral carina on the petiole, which is absent in the lasallei group.

Diversity

We recognise four species in the group, Orasema janzeni ( Costa Rica and Nicaragua), O. lasallei ( Costa Rica, Honduras, Mexico, Nicaragua), O. peckorum ( Brazil) , and O. vasquezi ( Colombia) .

Biology. Orasema lasallei was taken from a nest of Pheidole vorax (Fabr.) (Myrmicinae) .

Key to species of the O. lasallei species group

1. Frons vertically costate, lower face mostly smooth ( Figure 3a , 4e ); labrum with 6 – 12 digits ( Figure 3a,b ) ................................................................................................................................... 2

Frons rugulose or reticulate, lower face with some sculpture ( Figure 3f ); labrum with 4 – 8 digits ( Figure 3 f ).............................................................................................................................. 3

2. Hind femur yellow ( Figure 3c, d )............................ ............................ Orasema lasallei sp. nov.

Hind femur dark brown medially ( Figure 4d ) ............................ Orasema vasquezi sp. nov.

3. Labrum with 8 (♀) or 6 (♂) digits; frons rugulose-reticulate; basal area of speculum bare; postmarginal vein 2.2× as long as stigmal vein .................... Orasema peckorum sp. nov.

Labrum with 4 – 6 digits; frons finely reticulate; basal area of speculum closed by broad band of setae; postmarginal vein 1.4 – 2.2× as long as stigmal vein.......................................... .......................................................................................................................... Orasema janzeni sp. nov.

Figures

Figure 2. Antennae. an, anellus; Fu8, funicular 8. Scale bar = 0.25 mm.

Figure 3. (a–c) Orasema lasallei sp. nov. ♀ holotype: (a) head; (b) mouthparts (c) head and mesosoma. (d) O. lasallei ♂, head and mesosoma. (e–f) Orasema janzeni sp. nov. ♀ holotype: (e) head and mesosoma; (f) lower face. (g) O. janzeni ♂: habitus.

Figure 4. (a–b) Orasema peckorum sp. nov. ♀ holotype: (a) habitus; (b) head and mesosoma. (c) O. peckorum ♂: habitus. (d–e) Orasema vasquezi, sp. nov., ♀ holotype: (d) habitus; (e) face. (f–g) O. masneri sp. nov., ♀ holotype: (f) habitus; (g) ovipositor, lateral view.