Anthidiellum (Pycnanthidium) sternale Pasteels

Eardley, Connal, 2018, Taxonomic revision of the sub-Saharan Anthidiellum Cockerell (Apoidea: Megachilidae: Anthidiini), Zootaxa 4402 (2), pp. 201-250 : 233-238

Anthidiellum (Pycnanthidium) sternale Pasteels

( Figs 26–28 )

Anthidiellum (Pygnanthidiellum) sternale PAStEELS, 1984: 96, 104, 155, MALE HOLOtyPE (SANC, EXAMINED) CRyStAL WAtER, BREEDSNEK, SOUtH AFRIcA.

Diagnosis. Within the species-group, identified by the upper female clypeal edge being more or less horizontal ( Fig. 1b ), the only unique female feature is the yellow hind basitasus. In A. apicatum and A. bipectinatum , this structure is at least partly black. Males in this species-group can be identified by unique combinations of characters in the structures of S4 and S5. In A. sternale , S4 is concave and tuberculate, and S5 has a short lateral comb.

Description. Female. Integument black, variable pale yellow maculation on lower face (clypeus dorsal margin, mediolongitudinal interantennal socket area, supraclypeus black sometimes ventral clypeus margin black), posterior vertex, always dorsal mesepimeron, ventral fore and middle tibiae, outer surfaces of all tibiae and basitarsi (hind basitarsus circumference blackish), lateral T1–T3, most of T4–T5, entire T6; T4–T5 distal margins black or translucent orange ( Fig. 26a–c ), metasomal venter orangish. Scopa white to very pale yellow. Lengths: face 2.0– 2.2 mm; scutum 1.5–1.8 mm; forewing 4.4–4.9 mm; body 5.2–5.9 mm. Structure. Head. Epistomal suture flattish above ( Fig. 1b ); lower epistomal suture projection between antennal sockets ( Fig. 1b ); preoccipital region rounded; omaulus carinate; fore and middle femora with sparse, plumose vestiture posteriorly; hind basitarsus wide (length1.5x width), propodeum coarsely striate dorsolaterally, vertical surface punctate dorsally, shiny ventrally; T4–T5 distal margins impunctate.

FIGURE 27. Anthidiellum sternale , MALE. A. FAcE. B. HABItUS. c. T6–T7. D. S5. E. GONOStyLUS. F. S8. g. &7. H. S 6. I. S5.

Male. Integument black with limited, variable pale yellow maculation on lower face (mediolongitudinal interantennal socket area black), vertex, upper gena, mandible, pronotal lobe, dorsal mesepimeron; ventral fore and middle femora, outer tibiae and tarsi, lateral T1–T3, most of T4–T5, entire T6–T7; distal margins of T1–T2 black, T3–T6 translucent orange (Fig. 27a–c), metasomal venter blackish-yellow (Fig. 27d). Lengths: head 2.0– 2.1 mm; scutum 1.5–1.6 mm; forewing 4.7–5.0 mm; body 4.7–5.3 mm. Structure. Head. Preoccipital region rounded on gena; omaulus carinate; forebasitarsus with long posterior fringe; propodeum coarsely striate dorsolaterally, vertical surface punctate dorsally, shiny ventrally; distal margins of T1–T6 impunctate;T6–T7 dorsal surfaces swollen mediolongitudinally (Fig. 27c); T7 distal edge pointed in dorsal view, obtusely pointed in ventral view (Fig. 27d); S2–S3 unmodified; S4 middle distal edge narrow, shallow concavity, black tubercles mediolaterally (Fig. 27d); S5 broadly concave, comb lateral about 5 short, thick, black setae (Fig. 27d, i); S6–S8 and gonocoxa as illustrated (Fig. 27d–i).

Distribution ( Fig. 28 ). Anthidiellum sternale is endemic to northern South Africa and eastern Botswana.

Material examined. Type material. Male paratype of Anthidiellum sternale : ‘Crystal Water Breedsnek Tvl. 4.xi.1962 H.N. Empey, Anthidiellum (Pygnanthidiellum) sternale n.sp. J. Pasteels det., 1967, Paratype, SANC Pretoria Database HYMA 19081, PARATYPE Anthidiellum (Pygnanthidiellum) sternale PARATYPE, BBSLID6494’.

Additional material. Botswana. Serowe, Farmers Brigade, 5km SE, 2226BD, 17.ii.1984, 1988, P. Forchhammer (3♀ SANC) . South Africa. Skukuza, 24.59S 31.35E, 20.xii.2010, 21.xi–3.xii.2011, C. Eardley (6♀ 6♂ SANC) . SANC; ‘ South Africa Tvl . Nylsvley Nature Reserve 24.39S 28.42E, 10–11.xii.1979, C.G. Moolman, Allotype, Anthidiellum (Pygnanthiellum) sternale n.sp. J. Pasteels det., 1983’, SANC.

FIGURE 30. Anthidiellum bipectinatum , MALE. A. FAcE. B. HABItUS. c. T6–T7. D. S5. E. GONOStyLUS. F. S8. g. S7. H. S 6. I. S5.

Figures

FIGURE 1. Anthidiellum, FEMALE,FAcE SHOWINg SHAPE OF cLyPEUS.A.DIStINctLy ROUNDED ABOVE.B.SLIgHt ROUNDED ABOVE.

FIGURE 26.Anthidiellum sternale.A–B FEMALE.A.HABItUS.B.FAcE.c–D.MALE.c. HABItUS.

FIGURE 28.KNOWN DIStRIBUtION OF Anthidiellum sternale.