A Revision of Perdita (Xerophasma) Timberlake (Hymenoptera: Andrenidae) Griswold, Terry Miller, Wensdae Zootaxa 2010 2010-06-24 2517 1 1 14 6V3B3 Griswold & Miller Griswold & Miller 2010 [151,789,562,588] Insecta Andrenidae Perdita Animalia Hymenoptera 5 6 Arthropoda species vespertina sp. nov. Xerophasma  ( Figs. 3, 8, 13, 18, 22)  Female. Length: 7.0– 8.5 mm. Forewing length: 6.2–7 mm. Head, mesosoma dark brown to nearly black except: cream-colored labrum, clypeus, paraocular area below level of fovea, spot on vertex between and slightly dorsal to lateral ocelli (sometimes reduced to point), postgenal area along margin of eye, pronotum except spot laterally, 'U'-shaped markings on mesoscutum with base of 'U' at scuto-scutellar margin, arms of 'U' running longitudinally between parapsidal and admedial lines, scutellum, metanotum, tegula, propodeum laterally, legs. Costal vein, prestigma dark. Stigma slightly darkened, ventral margin distinctly darkened. T1-5 with subapical brown bands on otherwise caramel-colored terga. Frons finely reticulate. Mesoscutum, scutellum shiny, mesoscutum anteriorly and laterally slightly reticulate. Mesoscutum moderately densely, distinctly punctate, evenly covered with sparse long pale hair. Propodeal triangle somewhat shiny, finely reticulate. Mandible simple, without preapical tooth. Labrum with apical margin obtusely angulate. Clypeal width dorsally slightly greater than width of each subantennal area. Frontal line strongly raised halfway to median ocellus then strongly depressed to median ocellus. Facial fovea dull, linear, densely pubescent, extending from middle of antennal socket nearly to level of median ocellus. Ocellar area slightly inflated. Median ocellar diameter 1/4 width of interocular distance at level of median ocellus. Length of vertex behind lateral ocellus less than ocellar diameter. Forecoxa with long, erect, slightly plumose, straight hair; mesepisternum ventrally with short, obliquely directed, straight hair. Length of marginal cell on wing margin twice apical width. Pygidial plate narrowly rounded.  Male. Length: 7.5–9.0 mm. Forewing length: 5.3–5.9 mm. Head, mesosoma, legs cream colored except: entire head slightly yellowed; dark brown on facial fovea, markings anterior to each of lateral ocelli, medially between lateral ocelli, line extending dorsally from median ocellus, marks sometimes forming ”V” between hindocelli on vertex, occasionally as rings around ocelli, sometimes along dorsal margin of eye orbit; brown subapical band on T1 and sometimes T2–4. T2 lateral fovea forming fine, sometimes dark, line. Sculpture, punctation, pubescence as in female. Clypeus dorsally about 1.5X width of subantennal area. Supraclypeal area not protuberant, without tuft of hair. Facial fovea pubescent, elliptical, minutely depressed, sometimes slightly tear-shaped with narrow end ventral, extending from level of ventral margin of median ocellus to slightly more than halfway to dorsal margin of antennal socket. Frontal line, ocellar diameter, forewing as in female. T7 with pygidial plate illdefined, with apical tuft of hair protruding from beneath apical margin. S8 as in Fig. 18. Genitalia as in Figs. 8, 13.   Type material.  Holotypefemale:  USA NEVADA, Clark County, Mesquite, 36°48.98' N 114°04.22' W,  26 May 1998,  Camissonia, T. Griswold, BBSL289459.  Paratypes: NEVADA, Clark County:  2 females, 7 males, same data as holotype;  1 female, St. Thomas Gap, 36°24.35' N 114°5.62' W,  8 Jun 1998,  Camissonia, T. Griswold;  2 females, 2 males, St. Thomas Gap, 36°24.45' N 114°05.58' W,  7 Jun 1998, pantrap, F. D. Parker;  2 females, Las Vegas Dunes Rec. Lds., 36°17.27' N 114°58.00' W,  22 May 1998, light blue pantrap, M. Andres, K. Receveur, K. Keen, C. Shultz; 1 female, 1 male, same except white pantrap; 1 male, same except dark blue pantrap;  1 female, SE of Overton, 36°31.32' N 114°26' W,  21 May 1998, yellow pantrap, C. Shultz, K. Receveur, K. Keen, M. Andres; 1 female, same except white pantrap; 2 females, same except light blue pantrap; 1 female, same except dark blue pantrap;  21 females, 13 males, Riverside,  11–21 May 1983, F. D. & J. H. Parker;  21 females, 55 males, Mesquite,  25 May 1973, at dusk,  Oenothera, G. Bohart;  6 females, 12 males, Glendale,  2 Jun 1973, P. F. Torchio;  12 females, 6 males, Toquap Wash, W Mesquite, 36°46'34"N 114°11'10"W,  24 May 2003, 19:30 h.,  Camissonia, D. Yanega;  2 males, Toquap Wash,  1 miN HwyI-  15, 485 m, N 36°46'39" W114°11'10",  25 May 2003,  Camissonia, D. Yanega;  1 female, 3 males, Kaolin Wash, S Overton, 36°30'42"N 114°26'39"W,  25 May 2003, D. Yanega;  1 female,  2.16 miSW Wechech Basin, 11S E755235 N4038290,  13 May 2005, flourescent yellow pantrap, R. Andrus, S. Higbee;  1 female,  0.4 miE St. Thomas Gap, 11S E760620 N4032979,  12 May 2005, white pantrap, D. Allen, E. Ahlstrom, R. Andrus, S. Higbee;  2 males,  3.9 miSSW Whitney Pocket, 11S E755045 N4039308,  26 May 2005, white pantrap, R. Andrus, S. Higbee; 1 male, same except flourescent yellow pantrap; 1 male, same except flourescent blue pantrap.  Holotypedeposited in the U.S. National Pollinating Insects Collection, Logan, Utah; paratypesin Logan and Riverside.   Diagnosis.Timberlake recognized this as a new species and gave it a manuscript name that remained unpublished at his death.  Perdita vespertinadiffers from all other  Xerophasmaexcept  P. celadonain the largely dark mesoscutum. The ocelli of  P. vespertinaare larger than in  P. celadona.Females differ from  P. celadonain the simple mandible, pale clypeus, and rounded rather than acute pygidial plate. Males differ in the absence of dark marks above the antennal sockets and the rounded rather than emarginate apex of S8. The scopa on the hindtibia is denser than in other  Xerophasma.  Range.Apparently endemic to Clark County, Nevadain the eastern Mojave Desert ( Fig. 27) where it was active at dusk. Known only from scattered low elevation, sandy localities from Las Vegas Dunes to Mesquite and St.Thomas Gap. Some specimens were labeled as collected on  Oenotherabut these were from plants now assigned to  Camissonia(Parker, personal communication).   Variation.Some individuals lack the intercalated second submarginal cell on one or both wings. The incidence varies among populations. In the Riverside population (n = 36) 22% have intercalated submarginal cell absent or incomplete on one wing; 11% missing on both wings. The cell was absent in only one specimen(1 %) of the Mesquite sample (n = 82) and none of the Glendale sample (n = 17). Two females from Glendale, Nevada1973 had the mesoscutum light, with the mesepisternum light dorsally but brown ventrally.   Etymology.From the Latin, “vesper”, meaning evening and west, in reference to the evening flight period and southwestern origin of the bee. 1998-05-26 United States of America Clark County 36.816334 Mesquite 11 -114.070335 5 6 1 Nevada holotype [770,1199,1829,1855] United States of America Clark County Clark County 5 6 1 Nevada paratype 1998-05-26 United States of America Clark County 36.816334 Mesquite 11 -114.070335 5 6 9 2 7 NEVADA paratype 1998-06-08 United States of America 36.405834 St. Thomas Gap 11 -114.093666 5 6 1 1 NEVADA paratype [276,1432,1904,1930] 1998-06-07 F. D. Parker United States of America 36.4075 St. Thomas Gap 11 -114.093 5 6 4 2 2 NEVADA paratype 1998-05-22 M. Andres & K. Receveur & Keen & Shultz United States of America 36.287834 Las Vegas Dunes Rec. Lds. 11 -114.96667 5 6 2 2 NEVADA paratype 1998-05-21 C. Shultz & K. Receveur & K. Keen & Andres United States of America 36.522 SE of Overton 743 -114.433334 6 7 1 1 NEVADA paratype 1983-05-11 1983-05-21 1983-05-11 F. D. & J. H. Parker United States of America Riverside 6 7 34 21 13 NEVADA paratype [312,1260,264,290] 1973-05-25 United States of America Mesquite 6 7 76 21 55 NEVADA paratype 1973-06-02 P. F. Torchio United States of America Glendale 6 7 18 6 12 NEVADA paratype 2003-05-24 W Mesquite United States of America 36.77611 Toquap Wash 19 -114.18611 6 7 18 12 6 NEVADA paratype 2003-05-25 United States of America 15485 Toquap Wash -36.7775 6 7 2 2 NEVADA paratype 2003-05-25 Wash, S & D. Yanega United States of America 36.511665 Overton 19 -114.44417 6 7 4 1 3 NEVADA paratype 2005-05-13 R Andrus, S & Higbee United States of America 2.16 mi SW Wechech Basin 6 7 1 1 NEVADA paratype 2005-05-12 R Allen & E. Ahlstrom & Andrus, S & Higbee United States of America 0.4 mi E St. Thomas Gap 6 7 1 1 NEVADA paratype 2005-05-26 R Andrus, S & Higbee United States of America 3.9 mi SSW Whitney Pocket 6 7 2 2 NEVADA paratype U. S. National Pollinating Insects Collection United States of America Utah 6 7 2 Utah holotype