Extracted from Studies of Halictinae (Apoidea: Halictidae), II: Revision of Sphecogastra Ashmead, Floral Specialists of Onagraceae by McGinley, J. R. (2003).
As Lasioglossum (Sphecodogastra) aberrans (Crawford).�Turner, 1966 [foraging activity, host plant biology, mating biology, predation, parasitism, nest site].
TYPE MATERIAL.�The holotype female, from the collection of the Bee Biology and Systematics Laboratory, Utah State University, has been deposited in the National Museum of Nat�ural History, Smithsonian Institution. It is in excellent condi�tion and is labeled "Antioch Calif.[oraia] IV[April]-4-[19]39 [handwritten]/GE Bohart Collector/HOLOTYPE Sphecodogas�tra antiochensis R.J. McGinley" [red label]. Paratypes are listed in "Specimens Examined," below.
ETYMOLOGY.�The specific name was a label manuscript name used by George E. Bohart, who along with P.H. Timber-lake was among the first workers to recognize this species as being distinct. As the name implies, this species is known only from the vicinity of Antioch, Contra Costa County, Cali�fornia.
DISTRIBUTION (Figure 92).�Sphecodogastra antiochensis is a geographically isolated species of this genus. It is known to occur only in the sand dune habitat of Antioch, Contra Costa County, California. Its host plant is a similarly isolated subspe�cies of primrose, Oenothera deltoides howellii (Klein, 1970). The nearest occurrences of another Sphecodogastra species I am aware of are two separate collections of S. lusoria from Delhi and Livingston, Merced County, California, approxi�mately 70 miles southeast of Antioch (Figure 92).
DIAGNOSIS.�Females: see "Diagnosis" for S. aberrans. Males: see "Diagnosis" for S. lusoria.
DESCRIPTION.�FEMALE: (1) Length 8.2-9.5 mm (mean = 8.8, n = 5); (2) wing length 2.6-3.0 mm (mean = 2.8, n = 5); (3) abdominal width 2.6-2.9 mm (mean = 2.7, n = 5).
Structure: (4) Head moderately elongate (Figure 72); length/width ratio 0.95-1.00 (mean = 0.98, n = 5). (5) Gena, at midpoint, slightly exceeding width of compound eye. (9) Clypeus projecting approximately 0.63 times its length below lower margin of eyes; (11) clypeal surface without median lon-gitudinal sulcation. (13) Ocular-ocellar distance exceeding distance between lateral ocellus and hind margin of vertex (oc�ular-ocellar space approximately 1.5 times lateral ocellar di�ameter); (14) distance between lateral ocelli slightly exceeding ocular-ocellar distance. (16) Inner margins of compound eyes converging below. (21) Scape reaching top of vertex; (22) pedicel subequal in length to flagellomere 1. (30) Mandible moderate in length, reaching opposing clypeal angle.
(40) Dorsal surface of propodeum about 0.59 times the length of scutellum and approximately 1.13 times the length of metanotum; (44) lateral propodeal carinae well developed, ex-tending to dorsal propodeal surface. (45) Inner hind tibial spur with 5-7 teeth, more numerous and somewhat longer than those of other Sphecodogastra species (Figure 59).
(46) Lateral edge of metasomal T2 rounded anteriorly, be�coming straight to faintly sinuate posteriorly.
Sculpture: (51) Supraclypeal area mostly polished, tessel-late only near lateral margins, (52) very densely punctate, most punctures separated by less then the width of their diameters. (53) Clypeus polished; (54) punctation extremely sparse, api�cal punctures only slightly larger than basal ones, most sepa�rated by at least three times their diameters. (55) Hypostoma striolate throughout.
(56) Mesoscutum somewhat dull, tessellate on anterior half, (57) punctation as in Figure 77, most punctures separated by 1-2 times their diameters. (63) Dorsal surface of propodeum ruguloso-striolate, nearly to posterior edge (Figure 27), (64) surface alveolated. (65) Tl shiny and polished, (66) punctation fine, moderately sparse, punctures separated by 1-2 times their diameters.
Coloration: (67) Abdomen dark brown. (69) Flagellum dark brown. (70) Tegula brown to light brown. (71) Wing membrane pale yellowish brown; veins and stigma amber. (72) Legs dark brown.
Vestiture: (74) Hairs on head pale yellowish brown. (75) Pubescence on thorax pale yellowish white; (76) mesoscutal hairs elongate, length approximately 1.5 times median ocellar diameter; mesoscutum and pleuron without short, suberect or adpressed hairs. (81) Basal hair bands on T2-T4 present, cov�ering basal one-fourth of tergal surface; moderately developed apical hair bands on T3 and T4.
MALE: As described for female except as follows: (1) Length 8.0-9.3 mm (mean = 8.5, n = 5); (2) wing length 2.2-2.6 mm (mean = 2.4, n = 5); (3) abdominal width 1.7-2.2 mm (mean = 2.0, n = 5). (4) Head (Figure 73) length/width ra�tio 1.08-1.11 (mean = 1.09, n = 5). (23) Flagellomere 2 approximately 2.0 times length of flagellomcre 1. (37) Median mesoscutal line impressed. (70) Teguia yellow-translucent to brown. (73) Short, adpresscd hairs on face extending dorsad to ocellar area, nearly enclosing median ocellus. (76) Mcsoscu-tum with moderately elongate hairs and extensive layer of short, adpresscd hairs; pleuron with short, adpresscd hairs.
Terminalia (Figures 78-81); (84) S7 lateral arms moder�ately well developed; (85) S8 moderately developed; apex of median process rounded; (89) rctrorsc membranous lobe narrow.
FLIGHT RECORDS (Figure 82).�Females of S. antiochensis examined in this study were collected from March through Au-gust, with most records (67%) collected during May. Male col-lections ranged from May through October, with an over-whelming number (96%) taken in June.
Turner (1966) reported the earliest records of female flight activity as 15 March and 5 April. During his 1964-1965 study, females were first active usually in late April. The flight period of this species normally extends through August; however, in 1965, unusual rainfall prolonged the season, with females and males being observed as late as 19 and 22 September, respec�tively. Turner indicated that Sphecodogastra antiochensis ap�parently produced two generations each year.
REMARKS.�Sphecodogastra antiochensis is known exclu�sively from the bluffs of Antioch, Contra Costa County, Cali�fornia, as is its host plant, Oenothera deltoides howellii (Klein, 1970). This area was recognized in 1980 as the Antioch Dunes National Wildlife Refuge, largely for the protection of the en�dangered Lange's metalmark butterfly (Apodemia mormo langei) and its host plant, Eriogonum nudum (Caterino, 1997). Caterino indicated that under protection and proper dune man�agement the situation for the butterfly and its host plant looked relatively good.
Jerry Powell, who has long been involved with conservation efforts on behalf of the Antioch Dunes (e.g., Powell, 1978), added (Powell, pers. comm., 1996) the following:
The last time I checked on Sphecodogastra at Antioch was June 1982, and it was present then (22 individuals, 0630-0830). Although I have visited a few times in early A.M. in recent years to look Hot Apodemia larvae, I didn't look for Sphecodogastra. Since that time there has been a concerted effort to plant Oenothera, even including trucking in and contouring whole new sandhills, with considerable success. The plant is much more abundant now than in the lowest ebb, when weediness was choking out seedling establishment. The plants set seed, so I assume the bee population has increased. I don't know that it will be of any advantage to propose the population as endangered because the property is already in Federal hands and because they target the Oenothera as an endangered species in their recovery plans.
I agree with Powell's opinion that it is probably unnecessary to propose endangered species status for S. antiochensis, but I hope this unique Oenothera-Sphecodogastra relationship will be monitored in the future.
SPECIMENS EXAMINED.�574 (233 females, 341 males); 573 paratypes are designated and so labeled. They are deposited in the following collections: KU, NMNH, UCB, UCR, UIM, UNL, and USU.
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