Coelioxys (Schizocoelioxys) Mitchell, 1973

Rocha Filho, Léo Correia Da & Packer, Laurence, 2017, Phylogeny of the cleptoparasitic Megachilini genera Coelioxys and Radoszkowskiana, with the description of six new subgenera in Coelioxys (Hymenoptera: Megachilidae), Zoological Journal of the Linnean Society 180 (2), pp. 354-413 : 404

= Coelioxys (Schizocoelioxys) Mitchell, 1973 syn. nov.

Type species: Coelioxys alata Forster, 1853 .

Diagnosis: This subgenus can be differentiated from all the other subgenera based upon the mandible that is angled dorsally on the outer surface in females ( Fig. 81 ). Coelioxys (Paracoelioxys) spp. are similar to species of C. (Boreocoelioxys), but can be distinguished by the postgradular grooves of T 2 – T 3, which are broadly interrupted medially in the former (Fig. 25) and complete in the latter ( Fig. 24). They can also be differentiated from species of both of the new subgenera described herein, C. (Melissoctonia) subgen. nov. and C. (Rozeniana) subgen. nov., as well as from all other subgenera, by the following combination of characteristics. Axilla very short, free apical portion much shorter than basal portion, and not produced beyond posterior margin of mesoscutellum ( Fig. 71 ); apical fascia on T 1 nearly absent, restricted to the lateral margins of tergum; apical fasciae on T 2 – T 5 reduced medially or slightly interrupted. Female: mandible angled ( Fig. 81 ); S6 apex elongate, longer than broad, notches acute, narrow ( Fig. 26 ). Male: postgradular area of T 2 with sublateral, elliptical, slender fovea on each side ( Fig. 88 ) ( Baker, 1975: fig. 25B) and gonocoxa subapically not compressed ( Fig. 94L) ( Baker, 1975: fig. 19F).

Comments: This subgenus had previously been regarded as a synonym of C. ( Coelioxys s.s.) (see comments on that subgenus above), whereas C. (Schizocoelioxys) was synonymized under C. (Boreocoelioxys) by Michener (2007). The subgenus C. (Paracoelioxys) is resurrected here based on the phylogenetic results (see Results and Discussion). Whereas C. (P.) alata is Palaearctic, C. funeraria is restricted to North America ( Ascher & Pickering, 2015).

List of species: C. alata and C. funeraria . Some other Palaearctic species, Coelioxys hosoba Nagase, 2003 , Coelioxys hiroba Nagase, 2003 , Coelioxys inermis (Kirby, 1802) , Coelioxys mandibularis Nylander, 1848 , and Coelioxys elongata (Lepeletier, 1841) , might also belong to this subgenus as they share the modified mandible in the female.

Figures

Figures 81 and 82. Female, frontal view of head (outer surface of mandible indicated by black arrows): 81, Coelioxys funeraria; 82, Coelioxys conoidea. Scale bars: 1.5 mm.

Figures 69–72. Female. 69, Coelioxys cayennensis: dorsal view of mesoscutellum (for posterior margin). 70, Coelioxys praetextata: lateral view of S1 (basomedial area indicated by black arrow). 71, Coelioxys alata: dorsal view of mesoscutellum (for posterior margin). 72, Coelioxys funeraria: lateral view of S1 (basomedial area indicated by black arrow). Scale bars: 1.5 mm.

Figures 26–29. 26, female, Coelioxys porterae: dorsal view of T6 and S6. 27, male, Coelioxys sayi: dorsal view of T2 (fovea indicated by red arrow). 28, female, Coelioxys quadridentata, dorsal view of T6 and S6. 29, male, Coelioxys sodalis: dorsal view of T2 (punctate area indicated by red arrow). Scale bars: 1.5 mm.

Figures 87–90. 87, 88, Coelioxys rufescens: 87, female, ventral view of S6 (S6 notch indicated by black arrow); 88, male, dorsal view of T2 (fovea indicated by black arrow). 89, 90, Coelioxys conoidea: 89, female, dorsal view of T6 and S6; 90, male, dorsal view of T2 (fovea indicated by black arrow). Scale bars: 1.5 mm.