Stelis imperialis

Parker, Frank D. & Griswold, Terry, 2013, New species of the cleptoparasitic bee genus Stelis (Hymenoptera: Megachilidae, Anthidiini) from the Nearctic Region, Zootaxa 3646 (5), pp. 529-544 : 536-537

Stelis imperialis , n. sp

( Figs. 7 , 17 , 27 , 37 )

Diagnosis. This species can be distinguished from all Nearctic Stelis by the combination of tegula red, second recurrent vein ending on marginal vein basal to second transverse cubital vein, head without white integumental markings, terga black with some reddish coloration and complete subapical white bands, terga with complete apical hair bands. In addition, females with S6 rounded, not enclosed by T6 and males with margin of S3 produced medioapically, with mediolongitudinal welt extending basally one-third length of sternum.

Description. Female. Length 6.5mm; forewing 4.7mm long. Black, except following parts reddish-brown: mandible medially, mouthparts, flagellomeres (more brownish), femora apically, tegula, wing bases, terga, sterna medioapically; light yellow spot at bases of tibiae, subapical bands on terga, markings on T1, T2 entire with lateral apical surrounded spot, on T3 – T5 band not complete laterobasally; wings mostly hyaline. Pubescence white; on face long, thick, plumose; on vertex, scutum, scutellum, metanotum, long, erect, less plumose, these areas plus mesosoma and legs also clothed with dense recumbent shorter plumose hairs; fore, midtibiae with long, scraggly hairs beneath; terga clothed with short erect hairs, apically fringed with longer, thickly plumose hair bands; sterna covered with longer, plumose hair. Punctation coarse, punctures small, deep, contiguous on head, metasoma, separated on scutum, scutellum; basal zone of propodeum with cells laterally; S6 more closely punctate than preceding sterna (surface appears duller). F1 apically, F2 contrasting in sculpture, of equal length, combined lengths of F1 and F2 subequal to F10; head broader than long; genal width less than width of eye; IOD <(0.9X) OOD, OOD> (1.1X) LOD, IOD> (3X) LMOD; pronotal lobe with anterior carina; scutellum overhanging metanotum; apical tibial spines minute; second recurrent vein ending basad second transverse cubital; T1 ~ 3X as long as wide, T2 – T4 ~2.7X as long as wide; in lateral view T2 – T5 indented subapically; T6 wider (1.6X) than long, apical margin rounded ( Fig. 17 ); S6 slightly wider than long, pseudomargin produced apically to rounded point.

Male. Similar to female except: S1 with conical median subapical swelling, apical margin indented, rounded apically, fringed with plumose hair band; S2 – S6 forming basin-like median depression; S2 with medioapical margin bent down, with complete apical plumose hair band; S3 with margin produced medially into blunt V-shaped lobe, with low keel extending 1/3 length from apical margin of sternum, apical margin fringed with plumose hair band ( Fig. 27 ); S4 slightly produced medioapically, with fine toothed comb 0.2X width of sternum, medially with oval hair-filled depression and lateral patches of plumose hair, apically fringed with plumose hair band ( Fig. 37 ); apical margin of S5 with wide, shallow V-shaped emargination, with plumose hair patches mediolaterally, apically with plumose hairs only laterally; S6 with apical margin flat, without plumose hair band, S7 with small medioapical projection.

Type Material. Holotype female. “Glamis Cal. Imperial Co.”/”F.D.Parker Collector”/”Rearing No. 2902E”, [ex nest of Hoplitis xerophila ]. Paratypes. CALIFORNIA, Imperial Co: 2 Ƥ, same data as holotype except rearing number; Riverside Co: 1 Ƥ, Mecca, 7 Mar 1984, KW Cooper; 1 Ƥ, Palm Springs, 30 Mar 1916, CL Fox; San Bernardino Co: 17 Ƥ, 6 3, Winston Wash, reared, T Griswold, ex cells of H. xerophila . 1 3, Bayleaf Flat, California, reared, ex nest of H. xerophila , FD Parker; San Diego Co: 1 Ƥ, Borrego Valley, 11 Apr 1969, EE Grissell. ARIZONA, Maricopa Co: 1 Ƥ, Gila River, 10 km S Arlington, 6 – 13 Apr 2010, ME Irwin; 1 Ƥ, same except 30 Mar – 6 Apr 2010; Pima Co: 1 Ƥ, Tucson, 14 Apr 1957, AD Telford. UTAH, Garfield Co: 3 3, Calf Creek, reared, FD Parker; 1 3, Calf Creek, 5400', 24 May 1981, T Griswold; 1 Ƥ, same data except 23 may 1994; 1 3, same data except Cryptantha . Holotype deposited in BBSL, paratypes in BBSL, CAS, UCDC.

Biology. This parasite is associated with the two species of Hoplitis subgenus Xerosmia, H. xerophila (Cockerell) and H. zuni (Parker) , whose hosts nest in stems (Parker 1978).

Distribution. Found in the deserts of southern California and Arizona north to the Colorado Plateau of southern Utah.

Etymology. Derived from the region where this species was first found, the Imperial Valley of California.

Figures

FIGURES 1 – 10. Female habitus in profile view. 1. Stelis joanae, 2. S. occidentalis, 3. S. lamelliterga, 4. S. broemelingi, 5. S. paiute, 6. S. anthocopae, 7. S. imperialis, 8. S. anasazi, 9. S. shoshone, 10. S. alta. Scale bar = 1 mm.

FIGURES 11 – 20. Apex of female metasoma in posterior view. 11. Stelis joanae, 12. S. occidentalis, 13. S. lamelliterga, 14. S. broemelingi, 15. S. paiute, 16. S. anthocopae, 17. S. imperialis, 18. S. anasazi, 19. S. shoshone, 20. S. alta. Scale bar = 0.5 mm.

FIGURES 21 – 30. Male S 3 in ventral view. 21. Stelis joanae, 22. S. occidentalis, 23. S. lamelliterga, 24. S. broemelingi, 25. S. paiute, 26. S. anthocopae, 27. S. imperialis, 28. S. anasazi, 29. S. shoshone, 30. S. alta. Scale bar = 0.5 mm.

FIGURES 31 – 40. Male S 4 in ventral view. 31. Stelis joanae, 32. S. occidentalis, 33. S. lamelliterga, 34. S. broemelingi, 35. S. paiute, 36. S. anthocopae, 37. S. imperialis, 38. S. anasazi, 39. S. shoshone, 40. S. alta. Scale bar = 0.5 mm.