Scrapter pyretus Davies, 2006

Davies, Gregory B. P. & Brothers, Denis J., 2006, Morphology of Scrapter (Hymenoptera: Anthophila: Colletidae), with description of three new species and taxonomic status of five Cockerell taxa, African Invertebrates 47, pp. 135-183 : 170-173

Scrapter pyretus Davies , sp. n.

Figs 110–114

Etymology: Greek pyretos (burning hot, fiery). In allusion to the sweltering type locality in Namibia, and the fiery orange metasoma in both sexes.

Diagnosis: S. pyretus is a tiny black bee bee with an orange-red metasoma ( Fig. 114 ). Other noteworthy features are the deep, slit-like facial foveae, largely yellow mandibles, slight yellow tinge to pronotal lobe, tuberculate metabasitibial plate in the ^, and simple claws in the ^. The ơ keys to S. luridus because of the orange-yellow scape. S. pyretus ơ, though, is easily distinguished from S. luridus ơ by (a) the orangish metasoma (black in S. luridus ), (b) its smaller body length (approximately 8–9 mm in S. luridus ), (c) the different facial foveae (shallow and indistinct in S. luridus ), (d) the near-absent lateral pronotal ridge (sharp and well-defined in S. luridus ) and (e) the strongly divergent terminalia (see Eardley 1996, figs 78–80 for S. luridus ). In general facies, the ơ S. pyretus recalls S. avius or S. calx , but the mostly orange metasoma and orangish scape are distinctive. The ^keys out at S. avius , and is superficially similar to that species. The ^S. pyretus can be distinguished by (a) its largely yellow mandibles (dark red-brown to black in S. avius ), (b) blunt lateral pronotal ridge (sharp-edged and welldefined in S. avius ), and (c) slit-like facial fovea with the bottom of the fovea not visible ( S. avius facial foveae are also narrow but the bottom is clearly visible with reticulate sculpture).

Description:

Male.

Measurements (n =4): total body length 5.8 mm, head length 1.2 mm, head width 1.5 mm, lower interocular distance 0.8 mm, upper interocular distance 1.0 mm, interantennal distance 0.3 mm, antennocular distance 0.2 mm, length of clypeus 0.4 mm, length of eye 0.9 mm, length of facial fovea 0.3 mm, maximum width of facial fovea 0.02 mm, mesoscutum length 0.8 mm, mesosoma length 1.8 mm, forewing length 3.7 mm, pterostigma length 0.5 mm, maximum width of pterostigma 0.2 mm, marginal cell length 0.9 mm, length of marginal cell beyond pterostigma 0.7 mm, length of freepart of marginal cell 0.6 mm, metatibia length 1.1 mm, metabasitarsus length 0.7 mm.

Vestiture: Clypeus, supraclypeal area, and lower paraocular area thickly covered in decumbent, white, bristly hairs (integument obscured). Vertex with sparse, erect, longish, white hairs. Gena densely covered in shortish, white hairs. Mesoscutum fairly densely covered in short, whitish, erect hairs (integument visible). Scutellum and metanotum similar to mesoscutum. Mesepisternum hairless dorsally, but thickly hairy below. Metepisternum largely nude. T2–4 with bands of very short, bristly, white hairs along graduli. Sterna very weakly hairy with feeble posterior hairbands S3–5.

Integumental colour: Mostly black except for metasoma and legs. Scape, pedicel and flagellomeres orange-yellow, dorsal surface of flagellomeres dark brown. Mandible largely yellow except for apical black tip. Pronotal lobe dark brown with slight yellow tinge. Protibia and protarsi yellow. Profemur and protrochanter brown with orange tinge. Mid- and hindlegs similar colour pattern to foreleg. T1 black, slightly orange posteriorly. T2 orange (fovea and area immediately adjacent black). T3 orange-brown. T4–6 black. T7 orange.

Head (Prosoma): Clypeus densely punctate (interspace <0.5× puncture diameter), smooth and shiny interspaces, no medio-longitudinal clypeal sulcus, lower edge of clypeus emarginate. Supraclypeal area protuberant, anterior face of supraclypeal area densely punctate (interspace <0.5× puncture diameter). Paraocular area and frons densely punctate. Frontal line apically carinate. Facial fovea very narrow, slit-like. Vertex densely punctate, not carinulate. Gena densely punctate. Inner eye orbits diverging slightly dorsally, proportion of lower to upper interocular distance 0.8:1. Antenna rather short, just reaching tegula.

Mesosoma: Pronotal lateral ridge weak. Mesoscutum densely punctate (interspace 0.5–1× puncture diameter), interspaces smooth and shiny, median line weakly impressed. Scutellum and metanotum similar sculpture to mesoscutum. Propodeum strongly angulate. Propodeal triangle with irregular network of carinae on basal area. Basal area of propodeal triangle quite long, 2× length of metanotum. Mesepisternum fairly dense punctation, slightly roughened between punctures. Upper half of metepisternum with three transverse carinae in some specimens.

Legs: Metabasitibial plate with only posterior carina present, small apical tubercle sometimes present. Pretarsal claws deeply cleft.

Metasoma:Tergal discs with dense punctation and smooth interspaces.T2 fovea elongate ovoid. Pygidial plate absent.

Terminalia: Gonobase large, inner margin of gonocoxite toothed posteriorly, gonoforceps curved inwards posteriorly, lightly hairy ( Fig. 110 ). S6 weakly emarginate posteriorly, weak ridge adjacent to apodemes ( Fig. 111 ). S7 posteriorly tapering to weakly emarginate point, outer margin of anterior arms with small protuberance ( Fig. 112 ). S8 apical process short, fairly hairy, rounded ( Fig. 113 ).

Female.

Measurements (n =4): total body length 6.3 mm, head length 1.3 mm, head width 1.7 mm, lower interocular distance 1.0 mm, upper interocular distance 1.1 mm, interantennal distance 0.3 mm, antennocular distance 0.3 mm, length of clypeus 0.5 mm, length of eye 1.0 mm, facial fovea length 0.5 mm, maximum width of facial fovea 0.02 mm, mesoscutum length 0.9 mm, mesosoma length 2.0 mm, forewing length 3.9 mm, pterostigma length 0.5 mm, maximum width of pterostigma 0.2 mm, marginal cell length 1.0 mm, length of marginal cell beyond pterostigma 0.8 mm, length of freepart of marginal cell 0.7 mm, metatibia length 1.2 mm, metabasitarsus length 0.7 mm.

Vestiture: Face largely naked, sparse white hairs surrounding antennal sockets and feeble fringe to ventral margin of clypeus. Sparse, scattered, short white hairs on mesoscutum, thicker on scutellum and metanotum. Sides of mesosoma weakly hairy.T2–4 with bands of short, white hairs along graduli, expanding out onto disc on T4. Prepygidial fimbria thick, white, bristly hairs. Metatibial scopa all white hairs. S2 plumose, white hairs, remainder of sterna with sparse, white hairs. Brush on anterior (outer) surface of probasitarsus with simple hairs.

Integumental colour: Mainly black. Scape and pedicel brownish with slight orange tinge. Flagellomeres ventrally yellow, dorsally dark brown. Mandibles mostly yelloworange. T1–4 all orange. T5 mainly black. T6 orangish. Trochanter and femur on all legs brown with orange tinge. All tibia and tarsi orange-yellow.

Head (Prosoma): Clypeus with fairly dense punctation (interspace 1–1.5× puncture diameter), interspaces shiny and superficially smooth (but very faintly reticulate), no medio-longitudinal clypeal sulcus, lower edge of clypeus medially emarginate. Supraclypeal area strongly protuberant above adjacent antennal sockets. Anterior face of supraclypeal areas with rather sparse punctation, shiny with faint reticulation. Paraocular area, frons and vertex densely punctate (interspace 0.5–1× puncture diameter), interspaces smooth and shiny, vertex not carinulate. Frontal line apically carinate. Facial fovea slit-like. Eyes diverge very slightly dorsally, proportion of upper to lower interocular distance 1.0:1.1. Antenna just reaches tegula.

Mesosoma: Lateral ridge of pronotum weak. Mesoscutum densely punctate (interspace 0.5–1× puncture diameter), anterior interspaces with faint reticulation, remainder smooth. Median line moderately impressed, notaulus very weak and barely evident. Scutellum sparsely punctate, interspaces shiny, superficially smooth with very faint reticulations. Propodeum strongly angulate. Basal area of propodeal triangle with short, longitudinal carinae, remainder of triangle roughened. Basal area of propodeal triangle approximately 1.7× longer than metanotum.Mesepisternum densely punctate with reticulate interspaces, pre-episternal groove pitted throughout.

Legs: Metabasitibial plate reduced to a ring of seven to nine irregularly-shaped tubercles. Pretarsal claws simple.

Metasoma: Tergal discs with dense punctation and smooth interspaces. T2 fovea ovoid. Pygidial plate weakly tapering, rounded, dorsal surface smooth.

Terminalia:T7 sub-quadrate with moderately produced apodemal region, posterior edge curved and slightly produced ventro-posteriorly, spiracle placed far back but not opening onto posterior edge, lateral lamina fairly narrow (approximately 0.2× breadth of lamina spiracularis). Dorsal arm of furcula sub-equal in length to ventral arms. Condylar ridge area of T8 strongly curved. Apodeme of T8 extends beyond tergum.

Holotype: ơ NAMIBIA: Gaub Pass (23°30'S: 15°46'E), 19.iii.1997, F.W. & S.K. Gess ( AMGS).

Paratypes: 6ơ and 4^with same label data as holotype ( AMGS) and 7ơ and 8^from Namibia, Swakop River (22°41'S: 14°35'E), on road to Goanikontes, 11.iv.1998, F.W. & S.K. Gess ( AMGS) .

Distribution: Namibian endemic, only known from the Gaub Pass and Swakop River area.

Biology: Specimens (both sexes) were caught visiting the yellow flowers of Tetraena (= Zygophyllum ) simplex (L.) Beier & Thulin ( Zygophyllaceae ) in dry river-beds. The bees have been captured in March–April, suggestive of a late summer bee.

Figures

Figs 110–113. Scrapter pyretus sp. n., terminalia: (110) genitalia (dorsal and ventral views), (111–113) S6–8. Scale bar = 0.4 mm.

Fig. 114. Lateral view of female Scrapter pyretus sp. n.