Megachile (Eutricharaea), Thomson

Praz, Christophe, Al-Shahat, Ahmed M. & Gadallah, Neveen S., 2021, Taxonomic revision of the subgenus Eutricharaea Thomson in Egypt, with a key to the species and the description of two new species (Hymenoptera, Anthophila Megachilidae, genus Megachile Latreille), Zootaxa 5032 (3), pp. 301-330 : 304-305

Subgenus Eutricharaea Thomson

Diagnosis: Female: Small- to medium-sized Megachile (rarely larger, e.g., in M. sedilloti ) mostly diagnosable in the field by the small size and the white scopa (often dark on S6 or S5 and S6). Additional diagnostic traits are given in Praz (2017) and are summarized here: Sterna nearly always with distinct apical fringes of white hairs beneath scopa. Depending on the species group (see Praz 2017), mandible 4- or 5-toothed, with cutting edge in third interspace only, sometimes recessed behind margin and difficult to see in front view. Species of the subgenus Anodonteutricharaea Tkalců, represented in Egypt at least by M. inornata Walker 1871 , are superficially similar; in those species, there are no apical fringes of white hairs on the sterna, and the basal seta of the female claws is comparatively long; in Eutricharaea , the basal seta is modified to a thick process ( Praz 2017: figs 5, 7). The only known species of Eurymella in Egypt, M. patellimana Spinola 1838 , has the scopa orange (with white apical fasciae on sterna), a particularly broad hind basitarsus (basitarsus more slender in Eutricharaea : Praz 2017: figs 28, 29), and a 4-toothed mandible with particularly acute tooth 1.

Male: Small to medium species (rarely larger), mostly diagnosable in the field by the presence of white vestiture on the disc of T6 and the multidentate preapical carina of T6. Additional diagnostic traits of Palearctic species ( Praz 2017) are summarized here: mandible always tridentate, with a triangular inferior process (lacking in Anodonteutricharaea and in M. (Eurymella) patellimana ) ( Praz 2017: fig. 8). Front coxa usually with a spine (lacking only in M. soikai Benoist 1961 ). T7 small, little visible, not produced into tooth. Front tarsi simple or conspicuously enlarged. M. (Eurymella) patellimana is characterized in the male by numerous conspicuous traits, in particular the strongly modified front tarsi and the produced and narrowed carina of T6 ( Praz 2017: fig. 49).

The delimitation and diagnosis of the species groups within Eutricharaea are given in Praz (2017); important criteria to recognize these groups are mentioned in the identification key below.