Perdita vesca Timberlake
Creators: name: Portman, Zachary M.
name: Neff, John L.
name: Griswold, Terry
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Andrenidae
Perdita
Perdita vesca

description: Perdita vesca Timberlake
Figs. 4 A, 19F–H, 20H–I, 21E–F, 22D–E, 23S, 24U, 31A, 53, 57F, 60G–H
Perdita (Heteroperdita) vesca Timberlake, 1968: 11, ♂♀. Holotype ♀ (CAS type no. 14749), Wadsworth, Washoe Co., Nevada, USA.
Diagnosis. Both sexes have an exceptionally variable coloration on the metasoma. In the typical form, the metasoma is tan with obscure, poorly defined dark spots (Figs. 19 G, 20H), however the coloration can range from entirely whitish-tan (Figs.19 F, 20I) to solidly brown (Fig. 19 H). The female can be further recognized by having the second medial cell present (Fig. 4 A), the pygidial plate triangular with the apex broadly and evenly rounded (Fig. 24 U), the head and mesosoma with greenish-bronze tint, and the head only slightly broader than long (Figs. 22 D–E). The male can be further recognized by the head and mesosoma greenish-bronze, the pygidial plate broadly truncate (Fig. 23 S), the tan legs that lack well-defined dark markings, and the metasoma equal in width or broader than the mesosoma.
Redescription of female. Length: 2.6 mm. Forewing length: 1.7 mm.
Coloration. Head (Figs. 22 D–E) and mesosoma base color black with greenish-bronze luster; clypeus variably marked, ranging from dark brown to tan; supraclypeal mark generally dark, sometimes with narrowly transverse tan mark; paraocular mark tan, narrowly transverse, often reduced or absent; mandible tan, tip reddish; labrum tan, often brownish on apical half; scape tan; antenna brown dorsally, tan ventrally; pronotal collar brown or black with slight metallic tints; pronotal lobe tan, sometimes darkened; legs tan except brown on all coxae and often with blotchy, nebulous brown markings medially on fore and mid femora, posterior face of mid tibia, medially on hind femur, and distal hind tarsi; wing veins ranging from light to dark brown; metasoma exceptionally variable, base color generally tan, T1–T4 generally with five nebulous brown spots: two baso-lateral, two apico-sublateral, and one basomedial (Fig. 20 H), coloration sometimes ranging from entirely whitish-tan (Fig. 20 I) to entirely brown; T2 fovea black; pygidial plate tan.
Structure and vestiture. Head slightly broader than long (Figs. 22 D–E); lateral areas and circle around antennal socket covered in dense recumbent white pubescence, vertex with sparse erect pubescence; eyes subparallel, slightly converging ventrally; facial fovea obscure, parallel to eye, extending from top of antennal socket 1/2 distance to apex of eye, generally more or less obscured by pubescence; mandible with small preapical tooth; labrum quadrate, 1.2X broader than long; disc of clypeus broader than high, convex, apically protruding slightly less than 1 OD from face; lateral extension reaching 1/3 distance to base of mandible; venter of head with abundant inward-facing broadly hooked hairs; mesosoma strongly tessellate, impunctate, slightly shiny; pronotal collar slightly impressed, humeral angle weak; mesepisternum and margins of scutum very sparsely covered by combination of recumbent and erect white pubescence; fore coxa with abundant, broadly hooked hairs; apex of mid tibia with some short, thick, curved setae; forewing with second medial cell present; metasoma oval, slightly narrowed basally, tapering apically, widest at T3 (Figs. 20 H–I); terga tessellate and impunctate; T2 fovea linear, slightly over 1/2 length of T2; pygidial plate triangular, apex strongly and evenly rounded (Fig. 24 U); hairs of prepygidial fimbria thin, sparse.
Redescription of male. Length: 2.4 mm. Forewing length: 1.8 mm.
Coloration. Head (Figs. 21 E–F) and mesosoma base color metallic greenish-bronze; clypeus tan; supraclypeal mark variable, ranging from a large transverse tan mark to entirely absent; paraocular mark tan, subtriangular to triangular, generally reaching level of antennal socket; subantennal area generally dark, often lightened to tan along margin of antennal socket or even entirely light; mandible tan, tip reddish; labrum tan, sometimes with basomedial dark spot; scape tan, more or less marked with brown apically on anterior face; antenna light brown dorsally, tan ventrally; pronotal collar generally lacking light markings, sometimes with pair of well-separated transverse marks on dorso-posterior margin; pronotal lobe tan; legs entirely tan except often with faint, nebulous brown marks medially on all femora and medially on mid and hind tibiae, hind tarsi often slightly darkened; wing veins dark brown; metasoma extremely variable, ranging from tan to dark brown, T1–T5 generally darkened along basal margin with poorly defined dark triangles basomedially and poorly defined large dark sublateral spots (Fig. 19 G), coloration often entirely dark brown (Fig. 19 H) or rarely entirely tan (Fig. 19 F); T2 fovea dark brown; pygidial plate tan or brown.
Structure and vestiture. Head subquadrate or quadrate, broader than long or width and length equal (Figs. 21 E– F); face, except for clypeus, lower supraclypeal area, and frons covered by sparse recumbent white pubescence; eyes slightly converging ventrally; mandible simple, extending to far side of labrum in repose; labrum quadrate, 1.5X broader than long; disc of clypeus broader than high, moderately convex, apically protruding less than 1 OD from face; lateral extension reaching 1/4 distance to base of mandible; head with sparse pubescence ventrally; mesosoma strongly tessellate, impunctate, slightly shiny; pronotal collar slightly impressed, humeral angle weak; mesepisternum and margins of scutum sparsely covered by combination of recumbent and erect white pubescence; hind tibia with sparse, short, slightly thickened hairs; metasoma broader or equal in width to mesosoma, broadly oval, wide basally, tapering apically, widest at T3 (Figs. 19 F–H); terga tessellate and impunctate; T2 fovea linear, slightly thickened, 1/3 length of T2; pygidial plate broadly triangular, apex broadly truncate and evenly rounded (Fig. 23 S); hairs of prepygidial fimbria thin, sparse.
Terminalia. S8 (Fig. 57 F) with spiculum triangular, bottom edge approaching slightly emarginate; lateral apodemes prominent, strongly curving downwards; apical portion moderately convex, quadrate, sides roughly parallel below, slightly converging above to truncate and slightly inflated apex; short hairs ventrally; lacking thinned cuticular area. Genital capsule as in Figs. 60 G–H. Gonostyli separated dorsally by narrow V-shape; dorsal lobe of gonostylus broad and squat; ventral lobe narrow with few hairs apically; volsella small, strongly curved dorsally; cuspis with multiple spicules on outer face; digitus smaller than cuspis with single spicule apically; penis valve narrow, parallel, slightly turned outwards at apex, extending well beyond rest of genitalia; endophallus extending slightly beyond level of penis valve.
Floral records. Asteraceae (2 ♂): Tetradymia sp. 2 ♂, Boraginaceae (18 ♂ 26 ♀): Nama sp. 2 ♂, Tiquilia nuttallii 16 ♂ 26 ♀, Fabaceae (5 ♂ 1 ♀): Astragalus sp. 5 ♂, Dalea sp. 1 ♀, Tamaricaceae (1 ♀): Tamarix sp. 1 ♀.
Phenology. Active from April to August.
Distribution. Great Basin (Fig. 31 A), USA.
Type material examined. Holotype data: ♀, NEVADA: Washoe Co.: Wadsworth, 23 June 1962, G.I. Stage, on Coldenia nuttallii [= Tiquilia nuttallii (Hook.) A.T. Richardson] (CAS type no. 14749). Allotype data: ♂, same data as holotype (CAS). Paratype data: 1 ♀, same data as holotype (UCRC).
Additional material examined. Total specimens: 70 ♂ 52 ♀. CALIFORNIA: Mono Co.: Fish Slough, ~ 7 mi N Bishop (37.48583 -118.41305): 1 ♀, 22 Jun 1978, J.D. Pinto, Dalea sp.. NEVADA: Churchill Co.: Sand Mountain, 25 mi SE Fallon (39.3163 -118.4128): 1 ♂, 17 Jun 1981, R.W. Rust; Clark Co.: Glendale, 20 mi W (36.7919 -114.8676): 12 ♀, 29 Apr 1973, P.F. Torchio, F.D. Parker; 35 ♂, 29 May 1973, P.F. Torchio, F.D. Parker; Overton, 8 mi S (36.4536 -114.4336): 2 ♂, 27 Apr 1972, G.E. Bohart, F.D. Parker, P.F. Torchio, Nama sp.; Elko Co.: Montello, 14.2 km NE (41.35367 -114.07985): 1 ♂, 7 Jul 2013, Z.M. Portman, Tiquilia nuttallii; Montello, 9 mi NE (41.35 -114.07): 1 ♀, 26 Jul 2000, F.D. Parker; Esmeralda Co.: Clayton Valley Dunes (37.6713 -117.6166): 1 ♂, 18 Aug 1998, F.D. Parker; Lyon Co.: Fernley (39.56531 -119.19343): 2 ♂, 1 Jun 1996, F.D. Parker, Tetradymia sp.; Nye Co.: 16 mi E Gabbs (38.8605 -117.623): 3 ♂ 2 ♀, 22 Aug 1998, F.D. Parker; Big Dune, 1.2 km NW (36.66179 -116.60863): 4 ♂ 2 ♀, 29 Apr 2013, M. C. Orr, T. nuttallii; Washoe Co.: Nixon, 4 mi N (39.8734 -119.3952): 1 ♀, 7 Jun 1996, F.D. Parker, Tamarix sp.; Nixon, 5 mi N (39.8868 -119.3882): 5 ♂, 7 Jun 1996, F.D. Parker, Astragalus sp.. OREGON: Harney Co.: Mickey Hot Springs, 5.8 km WSW (42.65795 - 118.41258): 2 ♂ 9 ♀, 18 Jun 2012, Z.M. Portman; Road to Mickey Hot Springs; BM 4125 0.9 km E (42.66242 - 118.42136): 4 ♂ 5 ♀, 17 Jun 2012, Z.M. Portman, T. nuttallii; Road to Mickey Hot Springs; BM 4127, 0.5 km SW (42.65692 -118.4108): 1 ♂, 18 Jun 2012, Z.M. Portman; 1 ♂ 4 ♀, 18 Jun 2012, Z.M. Portman, T. nuttallii; Road to Mickey Hot Springs; Mickey Hot Springs, 5.7 km WSW (42.65772 -118.41238): 5 ♂ 15 ♀, 18 Jun 2012, Z.M. Portman, T. nuttallii. UTAH: Box Elder Co.: Park Valley, 35 mi SW (41.446 -113.6842): 1 ♂, 24 Jun 1973, P.F. Torchio; Washington Co.: Santa Clara, 3 mi W (37.123 -113.687): 2 ♂, 30 May 1973, P.F. Torchio, F.D. Parker.
Remarks. Perdita vesca is widespread throughout the Great Basin and into the northern edge of the Mojave Desert. In general, the northern populations tend to be darker in color while the southern populations tend to be lighter. However, there is significant color variation within populations as well. In the southwestern portion of the range, the specimens are distinctly lighter (metasoma whitish and male faces light below the antennae) and the males appear to have slightly broader heads. However, no additional morphological differences could be found, even in the male terminalia. While there is the potential that P. vesca could represent a species complex, the variation in color, the lack of morphological characters, and the relative dearth of collection events through much of the likely range make it impossible to even speculate.
description: Published as part of Portman, Zachary M., Neff, John L. & Griswold, Terry, 2016, Taxonomic revision of Perdita subgenus Heteroperdita Timberlake (Hymenoptera: Andrenidae), with descriptions of two ant-like males, pp. 1-97 in Zootaxa 4214 (1) on pages 83-85, DOI: 10.11646/zootaxa.4214.1.1, http://zenodo.org/record/253086