Perdita exusta Portman & Griswold

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, Zootaxa 4214 (1), pp. 1-97 : 43-46

Perdita exusta Portman & Griswold , sp. n.

Figs. 19 C, 20D, 21D, 22C, 23D, 24E, 31B, 32, 56D, 58G–H

Diagnosis. The female of P. exusta has the metasoma yellowish-tan, often with vestigial dark spots laterally ( Fig. 20 D). It can be recognized from similar species by the combination of the second medial cell present (e.g. Fig 4 A), and the pygidial plate narrowly triangular and bluntly pointed ( Fig. 24 E).

Unlike the female, the metasoma of the male is dark brown with the terga more or less lightened to light brown or tan on the apical margins ( Fig. 19 C). It can be distinguished from all similar species by the shape of the pygidial plate, which is quite narrow with the apex slightly truncate ( Fig. 23 D). It can be further recognized by the face marks yellowish-tan, and the head broader than long and oval in shape, approaching subquadrate in some specimens ( Fig. 21 D).

Description of female. Length: 3.4 mm. Forewing length: 2.1 mm.

Coloration. Head ( Fig. 22 C) and mesosoma base color black with greenish-bronze or bluish metallic luster; clypeus whitish-tan, occasionally with pair of submedial faint dark vertical bars; supraclypeal mark whitish-tan, large, transverse; paraocular mark tannish-white, transverse, reaching level of summit of clypeus except in thin line along the eye not going above top of antennal socket; mandible whitish-tan, tip reddish; labrum whitish-tan, sometimes with small medial dark spot; scape tan; antenna light brown dorsally, tan ventrally; pronotal collar brown with pair of large, narrowly separated yellowish-tan transverse marks dorso-posteriorly; pronotal lobe tan; metapleuron and anterior propodeum ranging from entirely brown to entirely yellowish-tan ( Fig. 32 A); propodeum generally dark, rarely with pair of reduced yellow marks dorso-anteriorly; legs yellowish tan except occasionally with poorly-defined vestigial brown marks basally on fore femur, dorsoapical spot on hind femur, medially on hind tibia, and distal hind tarsi; wing veins ranging from tan to brown; metasoma yellowish-tan, except T1 with pair of C-shaped brown marks on anterior face, T1–T5 often with pair of small apico-sublateral brown spots and even smaller baso-lateral spots, spots often reduced or absent on apical terga, joints of terga often slightly darkened Fig. 20 D); T2 fovea dark brown; pygidial plate tan.

Structure and vestiture. Head broader than long ( Fig. 22 C); lateral areas and circle around antennal socket densely covered in recumbent white pubescence, vertex with combination of recumbent and erect pubescence; eyes subparallel, slightly converging ventrally; facial fovea diverging dorsally, oval, extending from top of antennal socket 2/3 distance to apex of eye, generally more or less obscured by pubescence; mandible simple; labrum quadrate, slightly less than 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 mostly 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 suboval, wide basally, tapering apically, widest at T3 ( Fig. 20 D); terga tessellate and impunctate; T2 fovea linear, 2/3 length of T2; pygidial plate narrow, triangular, apex bluntly pointed ( Fig. 24 E); hairs of prepygidial fimbria thin, sparse.

Description of male. Length: 2.8 mm. Forewing length: 1.9 mm.

Coloration. Head ( Fig. 21 D) and mesosoma base color black with greenish-bronze or bluish metallic luster; clypeus yellowish-tan; supraclypeal mark yellowish-tan, large, transverse; paraocular mark yellowish-tan, transverse to subtriangular, reaching level of summit of clypeus, except continuing in thin line along eye to level of top of antennal socket; mandible whitish-tan, tip reddish; labrum whitish-tan, sometimes with basomedial dark spot; scape yellowish tan, anterior face more or less brown medially; antenna light brown dorsally, tan ventrally; pronotal collar brown with pair of large, narrowly separated yellowish-tan transverse marks dorso-posteriorly; pronotal lobe yellowish-tan; legs tan except more or less marked with brown on coxae, dorsobasally on all femora, medially on hind tibia, and distal hind tarsi; wing veins dark brown; metasoma dark brown except T1–T6 more or less lightened to tan on apical margin ( Fig. 19 C); T2 fovea black; pygidial plate tan or brown.

Structure and vestiture. Head oval or subquadrate, broader than long ( Fig. 21 D); lateral areas and circle around antennal socket densely covered in recumbent white pubescence, vertex with combination of recumbent and erect 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 1 OD from face; lateral extension reaching 1/3 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 mostly covered by combination of recumbent and erect white pubescence; hind tibia with sparse, short, slightly thickened hairs; metasoma narrower or equal in width to mesosoma, narrowly oval, wide basally, tapering apically, widest at T3 ( Fig. 19 C); terga tessellate and impunctate; T2 fovea linear, slightly thickened, 1/3 length of T2; pygidial plate narrowly triangular, apex thin, slightly truncate ( Fig. 23 D); hairs of prepygidial fimbria thin, sparse.

Terminalia . S8 ( Fig. 56 D) with spiculum bifurcate basally, lateral apodemes not prominent, apical portion convex, longer than broad, sides expanding medially before converging slightly towards truncate apex; a short hairs ventrally; lacking an obviously thinned area. Genital capsule as in Figs. 58 G–H. Gonostyli separated dorsally by narrow V-shape; lobes of gonostylus nearly equal in length, extending slightly beyond level of penis valve; ventral lobe slightly longer than dorsal lobe with few sparse hairs along outer margin of apex; volsella much shorter than gonostylus; cuspis with multiple spicules on apex; digitus shorter and thicker than cuspis, lacking spicules; penis valve relatively close together, slightly converging above, slightly turned outward at apex; endophallus extending slightly beyond level of penis valve.

Floral records. Boraginaceae (54 ♂ 59 ♀): Heliotropium sp. 1 ♀, Nama sp. 30 ♂ 30 ♀, Tiquilia latior 20 ♂ 24 ♀, T. sp. 4 ♂ 4 ♀, Loasaceae (1 ♀): Eucnide sp. 1 ♀.

Phenology. S pring (April and May).

Distribution. Mojave Desert ( Fig. 31 B), USA. Known only from the northeastern part of Clark County, Nevada, USA.

Type material. Holotype data: ♀, NEVADA: Clark Co.: Blue Point Spr. (36.3912 -114.4295): 30 Apr 2004, S.M. Higbee, Tiquilia sp. ( BBSL, accession no. BBSL 578253 ) . Paratype data: (16 ♂ 20 ♀) NEVADA: Clark Co.: Beehive Rock, W, West Valley of Fire State Park entrance (36.4091 -114.5494) : 2 ♀, 21 May 1998, M. Andres, Tiquilia latior ; Blue Point Spr. (36.3912 -114.4295): 1 ♀, 30 Apr 2004, B. Hansen, T. sp.; 1 ♀, 30 Apr 2004, S.M. Higbee, T. sp.; Glendale, 20 mi E (36.4431 -114.4272): 11 ♂, 2 May 1986, P.F. & D.M. Torchio; 5 ♀, 2 May 1986, P.F. & D.M. Torchio, Nama sp.; Magnesite Wash, E (36.4928 -114.5313): 1 ♀, 6 May 1998, M. Andres, K. Keen, K. Receveur, C. Schultz; Mesquite, 14 mi SW (36.7236 -114.2453): 2 ♂, 4 May 1982, F.D. Parker; Overton, 8 mi S (36.4536 -114.4336): 2 ♂ 6 ♀, 27 Apr 1972, G.E. Bohart, F.D. Parker, P.F. Torchio, N. sp. (1 ♂ 1 ♀ UCRC); Riverside, 7.5 km SW; Virgin Valley ; New Gold Butte Rd (36.68514 -114.27375) : 1 ♂, 16 May 2012, Z.M. Portman, T. latior ; St. Thomas Wash (36.4377 -114.4317) : 3 ♀, 5 May 1998, M. Andres, C. Schultz, T. latior ; 1 ♀, 5 May 1998, T.L. Griswold, T. latior .

Additional material examined. Total specimens: 71 ♂ 49 ♀. NEVADA: Clark Co.: Beehive Rock, W, West Valley of Fire State Park entrance (36.4091 -114.5494) : 3 ♂ 3 ♀, 21 May 1998, M. Andres, Tiquilia latior ; 1 ♂ 1 ♀, 21 May 1998, M. Andres, K. Keen, K. Receveur, C. Schultz; Blue Point Spr. (36.3912 -114.4295): 2 ♂, 30 Apr 2004, B. Hansen, T. sp.; 2 ♂ 1 ♀, 30 Apr 2004, S.M. Higbee, T. sp.; Glendale, 20 mi E (36.4431 -114.4272): 7 ♂, 2 May 1986, P.F. & D.M. Torchio; 5 ♀, 2 May 1986, P.F. & D.M. Torchio, Nama sp.; Glendale, 32 mi SE(36.3217 - 114.4936): 1 ♀, 1 May 1986, P.F. & D.M. Torchio, Eucnide sp.; Las Vegas Dunes (36.2853 -114.9642): 1 ♂ 3 ♀, 1 May 1998, K. Keen, C. Schultz, T. latior ; 1 ♂ 3 ♀, 28 May 1998, K. Keen, C. Schultz; Las Vegas Dunes (36.286 - 114.9667): 2 ♂ 5 ♀, 22 May 1998, M. Andres, K. Keen, K. Receveur, C. Schultz; Logandale (36.622 -114.4844): 1 ♀, 27 Apr 1972, G.E. Bohart, F.D. Parker, P.F. Torchio, Heliotropium sp.; Mesquite, 14 mi SW (36.7236 - 114.2453): 8 ♂, 4 May 1982, F.D. Parker; Overton, 8 mi S (36.4536 -114.4336): 28 ♂ 14 ♀, 27 Apr 1972, G.E. Bohart, F.D. Parker, P.F. Torchio, N. sp.; Riverside to Freeway (36.7541 -114.2312): 1 ♂, 16 May 1983, F.D. & J.H. Parker; St. Thomas Wash (36.4377 -114.4317) : 4 ♂ 2 ♀, 5 May 1998, M. Andres, C. Schultz, T. latior ; 9 ♂ 4 ♀, 5 May 1998, T.L. Griswold, T. latior ; Valley of Fire State Park (36.4435 -114.528): 2 ♂ 6 ♀, 21 May 1998, K. Keen, K. Receveur, T. latior .

Etymology. From Latin exustus meaning “burned” or “burned out” in reference both to the color of the metasoma and the Valley of Fire where it was found.

Remarks. Perdita exusta was originally reported by Griswold et al. (1999) and again in Griswold et al. (2006) in reports to the Nature Conservancy and Clark County, NV. However, the species has not been described until now.

The structure of the male terminalia indicates that P. exusta is a close relative of P. arenaria and the other species with a yellow metasoma with dark spots. Apparently P. exusta has largely lost the distinctive spotted pattern.

Figures

FIGURE 4. Second submedial cell of forewing. (A) Perdita vesca female, present (BBSL 816135; Harney Co., OR). (B) P. prodigiosa female, 2 m-cu vein weakened dorsally (paratype, BBSL 344037; Clark Co., NV). (C) P. bellula female, absent / weakened (BBSL 316794; Clark Co., NV). (D) P. wasbaueri male, absent / weakened (BBSL 842242; Imperial Co., CA).

FIGURE 19. Miscellaneous male metasomas. (A) Perdita bellula, typical form (141678; Yuma Co., AZ). (B) P. bellula, variation (BBSL 817827; Riverside Co., CA). (C) P. exusta (141895; Clark Co., NV). (D) P. rhodogastra (BBSL 309170; Clark Co., NV). (E) P. rhodogastra, dark form with light band (BBSL 290131; Clark Co., NV). (F) P. vesca, light coloration (BBSL 904888; Nye Co., NV). (G) P. vesca, spotted (BBSL 816156; Harney Co., NV). (H) P. vesca, solid coloration (141789; Clark Co., NV). All scale bars 0.5 mm.

FIGURE 20. Miscellaneous female metasomas. (A) Perdita bellula, typical coloration (103744; San Bernardino Co., CA). (B) P. bellula, melanized (BBSL 316794; Clark Co., NV). (C) P. desdemona (paratype, UCRC 185342; San Bernardino Co., CA). (D) P. exusta (paratype, 141946; Clark Co., NV). (E) P. prodigiosa, light coloration (BBSL 344016). (F) P. prodigiosa, dark coloration (paratype, BBSL 344044; Clark Co., NV). (G) P. rhodogastra (BBSL 271666; Clark Co., NV). (H) P. vesca, dark typical coloration (BBSL 816172; Harney Co., OR). (I) P. vesca, light coloration (BBSL 904881; Nye Co., NV). All scale bars 0.5 mm.

FIGURE 21. Miscellaneous male faces. (A) Perdita bellula, large specimen (BBSL 842249; Imperial Co., CA). (B) P. bellula, small specimen (BBSL 817812; Mojave Co., AZ). (C) P. rhodogastra (BBSL 817150; Mojave Co., AZ). (D) P. exusta (141888; Clark Co., NV). (E) P. vesca, dark coloration (BBSL 816156; Harney Co., OR). (F) P. vesca, light coloration (BBSL 904888; Nye Co., NV). All scale bars 0.25 mm.

FIGURE 22. Miscellaneous female faces. (A) Perdita bellula (BBSL 813459; Imperial Co., CA). (B) P. desdemona (paratype, BBSL 289006; San Bernardino Co., CA). (C) P. exusta (paratype, 141952; Clark Co., NV). (D) P. vesca, dark coloration (BBSL 816172; Harney Co., OR). (E) P. vesca, light coloration (BBSL 904881; Nye Co., NV). (F) P. prodigiosa, dark coloration (paratype, BBSL 813546; Clark Co., NV). (G) P. prodigiosa, light coloration (paratype, BBSL 318844; Clark Co., NV). All scale bars 0.25 mm.

FIGURE 23. Male pygidial plates. (A) Perdita arenaria (BBSL 814703; Imperial Co., CA). (B) P. bellula (103717; San Bernardino Co., CA). (C) P. coldeniae (UCRC 277998; Imperial Co., CA). (D) P. exusta (141888; Clark Co., NV). (E) P. frontalis (BBSL 989204; Imperial Co., CA). (F) P. hippolyta (paratype, BBSL 844677; Culberson Co., TX). (G) P. hooki (note: the pygidial plate is from a dissected specimen and the lateral edges have been artificially enhanced to give a better idea of the lateral edges, paratype, BBSL 852902; Coahuila de Zaragoza, MEX). (H) P. maculosa (BBSL 668379; Clark Co., NV). (I) P. nuttalliae (paratype, BBSL 816190; Harney Co., OR). (J) P. optiva (BBSL 813428; Imperial Co., CA). (K) P. pilonotata (CAVE 17654; Eddy Co., NM). (L) P. prodigiosa (paratype, BBSL 344085; Clark Co., NV). (M) P. rhodogastra (UCRC 277717; Yuma Co., AZ). (N) P. scutellaris (DEVA 55305; San Bernardino Co., CA). (O) P. sexfasciata (141736; San Bernardino Co., CA). (P) P. sycorax (note: the picture is taken at an angle but it still accurately represents the shape the pygidial plate, paratype, 37225; Emery Co., UT). (Q) P. titania (pygidial plate is artificially outlined for better visibility, paratype, UCRC 166000; Imperial Co., CA). (R) P. trifasciata (141767; Chihuahua, MEX). (S) P. vesca (BBSL 816156; Harney Co., OR). (T) P. wasbaueri (BBSL 904842; Imperial Co., CA). (U) P. yanegai (UCRC 50407; Riverside Co., CA). Scale bar = 0.1 mm. All images are at the same scale.

FIGURE 24. Female pygidial plates. (A) Perdita arenaria (BBSL 289244; Clark Co., NV). (B) P. bellula (103744; San Bernardino Co., CA). (C) P. coldeniae (BBSL 813873; Imperial Co., CA). (D) P. desdemona (holotype, BBSL 289742; San Bernardino Co., CA). (E) P. exusta (paratype, 141946; Clark Co., NV). (F) P. frontalis (BBSL 813797; Imperial Co., CA). (G) P. hippolyta (paratype, BBSL 844647; Culberson Co., TX). (H) P. hooki (paratype, 141840; Terrell Co., TX). (I) P. maculosa (UCRC 179125; Riverside Co., CA). (J) P. nuttalliae (142005; Box Elder Co., UT). (K) P. optiva (BBSL 284974; Clark Co., NV). (L) P. pilonotata (neotype, UCRC 182770; Otero Co., NM). (M) P. prodigiosa (paratype, BBSL 319169; Clark Co., NV). (N) P. rhodogastra, pointed (FDP 102612; Maricopa Co., AZ). (O) P. rhodogastra, rounded (BBSL 271674; Clark Co., NV). (P) P. scutellaris (BBSL 904845; Imperial Co., CA). (Q) P. sexfasciata (BBSL 295303; Clark Co., NV). (R) P. sycorax (paratype, 37238; Emery Co., UT). (S) P. titania (holotype, BBSL 326372; San Bernardino Co., CA). (T) P. trifasciata (FDP 75046; Brewster Co., TX). (U) P. vesca (BBSL 339200; Nye Co., NV). (V) P. wasbaueri (141836; Imperial Co., CA). (W) P. yanegai (UCRC 221828; San Bernardino Co., CA). Scale bar = 0.1 mm. All images are at the same scale.

FIGURE 31. Distribution of (A) Perdita desdemona (triangles) and P. vesca (circles), (B) P. exusta (squares) and P. frontalis (stars). Scale bars = 100 km.

FIGURE 32. Perdita exusta (A) female lateral habitus (paratype, 141952; Clark Co., NV), (B) male lateral habitus (141888; Clark Co., NV). Scale bars = 1 mm.

FIGURE 56. Male S 8 in dorsal view. (A) Perdita arenaria (BBSL 814693; Imperial Co., CA). (B) P. bellula (BBSL 842486; Riverside Co., CA). (C) P. coldeniae (BBSL 813338; Yuma Co., AZ). (D) P. exusta (BBSL 578345; Clark Co., NV). (E) P. frontalis (BBSL 813814; Imperial Co., CA). (F) P. hippolyta (paratype, CAVE 4578; Eddy Co., NM). (G) P. hooki (paratype, BBSL 852902; Coahuila, MEX). (H) P. maculosa (BBSL 638408; Clark Co., NV). (I) P. nuttalliae (BBSL 816192; Harney Co., OR). (J) P. optiva (BBSL 814695; Imperial Co., CA). (K) P. pilonotata (CAVE 17654; Eddy Co., NM). (L) P. prodigiosa (BBSL 344096; Clark Co., NV). Scale bar = 0.25 mm. All images are at the same scale.

FIGURE 58. Male genital capsules in ventral and dorsal view. (A) Perdita arenaria dorsal and (B) ventral (BBSL 814693; Imperial Co., CA). (C) P. bellula dorsal and (D) ventral (BBSL 307306; Clark Co., NV). (E) P. coldeniae dorsal and (F) ventral (BBSL 817844; Riverside Co., CA). (G) P. exusta dorsal and (H) ventral (141875; Clark Co., NV). (I) P. frontalis dorsal and (J) ventral (BBSL 813814; Imperial Co., CA). (K) P. hippolyta dorsal and (L) ventral (paratype, CAVE 4578; Eddy Co., NM). (M) P. hooki dorsal and (N) ventral (paratype, BBSL 852902; Coahuila, MEX). Scale bar = 0.25 mm. All images are at the same scale.