Epeolus howardi Mitchell, 1962

Onuferko, Thomas M., 2018, A revision of the cleptoparasitic bee genus Epeolus Latreille for Nearctic species, north of Mexico (Hymenoptera, Apidae), ZooKeys 755, pp. 1-185 : 91-93

26. Epeolus howardi Mitchell, 1962 Figs 55, 56

Epeolus howardi Mitchell, 1962. N. C. Agric. Exp. Stn. Tech. Bull. 152: 447 (♀).

Diagnosis.

The following morphological features in combination (excluding any that are specific to the opposite sex of the one being diagnosed) can be used to tell E. howardi apart from all other North American Epeolus : the axilla is large, with the tip extending as far back as or beyond the posterior margin of the mesoscutellum, dilated laterally, and like the mesoscutellum ferruginous; the mesopleuron is closely (i≤1d) and evenly punctate; the metasomal terga are black; T1 has a distinct, although sometimes medially-interrupted, basal fascia; the mesoscutum and metasomal terga have bands of bright or pale yellow short appressed setae; at least the T1-T3 apical fasciae are distinctly interrupted medially; and the pseudopygidial area of the female is lunate with the apex <2 × the medial length. Epeolus howardi most closely resembles E. andriyi and E. floridensis , but in E. andriyi the axillae are shorter, not extending as far back as the posterior margin of the mesoscutellum, and in E. floridensis the mesoscutum and metasomal terga have bands of pale gray to white short appressed setae and T1 is (with few exceptions) ferruginous. Epeolus howardi is also similar to E. scutellaris , but in E. scutellaris the T1-T3 apical fasciae are complete or only very narrowly interrupted medially, and the pseudopygidial area of the female is lunate with the apex>2 × the medial length.

Redescription.

FEMALE: Length 8.6 mm; head length 2.2 mm; head width 2.9 mm; fore wing length 6.0 mm.

Integument coloration. Black in part, at least partially ferruginous on mandible, labrum, clypeus, antenna, pronotal collar, pronotal lobe, tegula, axilla, mesoscutum, mesoscutellum, metanotum, mesopleuron, legs, T1, pygidial plate, and metasomal sterna. Mandible with apex darker than rest of mandible; preapical tooth slightly lighter than mandibular apex. Antenna brown and orange in part. Pronotal lobe and tegula pale ferruginous to amber. Mesoscutum reddish brown along lateral margin and with pair of reddish-brown markings near posterior margin between midline and parapsidal line. Wing membrane dusky subhyaline, slightly darker at apex. Legs more extensively reddish orange than brown or black. T1 dark in general, not contrasting strongly with remaining metasomal terga, but reddish brown laterally.

Pubescence. Face with tomentum densest around antennal socket. Clypeus, upper paraocular and frontal areas, and vertexal area mostly exposed. Dorsum of mesosoma and metasoma with bands of off-white to pale yellow short appressed setae. Mesoscutum with paramedian band. Mesopleuron sparsely hairy, but tomentum moderately dense along margins. Metanotum with tomentum uninterrupted, uniformly off white. T1 with discal patch quadrangular and very wide, the basal and apical fasciae only narrowly joined laterally by few sparsely scattered pale hairs. T1-T4 with apical fasciae interrupted medially and narrowed before becoming somewhat broader laterally, T2 with fascia without anterolateral extensions of tomentum. T5 with two patches of pale tomentum lateral to and contacting pseudopygidial area. T5 with pseudopygidial area lunate, its apex less than twice as wide as medial length, indicated by silvery setae on impressed disc of apicomedial region elevated from rest of tergum. S5 with apical fimbria of coppery to silvery hairs not extending beyond apex of sternum by more than 1/4 MOD.

Surface sculpture. Punctures dense. Labrum with larger punctures than clypeus, but punctures of both equally dense (i<1d). Upper paraocular area sparsely punctate in part, the interspaces shining. Small impunctate shiny spot lateral to lateral ocellus. Mesoscutum, mesoscutellum, and axilla coarsely and densely rugose-punctate. Tegula densely punctate mesally (i≤1d), less so laterally (i=1-2d). Mesopleuron with denser (i≤1d) punctures in upper half than ventrolateral half (i≤2d), the interspaces shining. Metasomal terga with punctures very fine, dense (i≈1d), evenly distributed on disc; the interspaces shining somewhat.

Structure. Preapical tooth inconspicuous, blunt and obtuse. Labrum with pair of small subapical denticles, each preceded by small discrete longitudinal ridge. Frontal keel not strongly raised. Scape with greatest length 1.8 × greatest width. F2 noticeably longer than wide (L/W ratio = 1.7). Preoccipital ridge not joining hypostomal carina, from which it is separated by less than 1 MOD at its terminal. Mesoscutellum weakly bigibbous. Axilla large, its lateral margin (L) more than half as long as mesoscutellar width (W) (L/W ratio = 0.7) and tip extending beyond apex of horizontal dorsal portion of mesoscutellum; axilla with tip clearly visible, but unattached to mesoscutellum for less than 2/5 the medial length of axilla; axilla with lateral margin arcuate. Fore wing with three submarginal cells. Pygidial plate apically truncate.

MALE: Description as for female except for usual secondary sexual characters and as follows: F2 shorter, but still longer than wide (L/W ratio = 1.3); S4 and S5 with much longer coppery to silvery subapical hairs; pygidial plate apically rounded, with large deep punctures more or less evenly spaced throughout, with the interspaces shining.

Distribution.

Mid-Atlantic states to Texas (Fig. 56).

Ecology.

HOST RECORDS: According to Mitchell (1962), Colletes howardi Swenk is the suspected host of E. howardi .

FLORAL RECORDS: Mitchell (1962) indicated a floral association with Dalea pinnata (J.F.Gmel.) Barneby. Labels of examined voucher specimens further indicate associations with Heterotheca subaxillaris ssp. latifolia (Buckley) Semple, Symphyotrichum drummondii var. texanum (E.S. Burgess) G.L. Nesom, and Xanthisma texanum DC. ( Compositae ).

Discussion.

Epeolus howardi is a southeastern species that appears to be uncommon, or at least uncommonly collected. In general, there is little morphological variation among examined specimens except in integument coloration; the mesoscutum and mesopleuron range from varying degrees of ferruginous to entirely black, with differences not conforming to any discernable geographic pattern. Based on known records, adults of E. howardi are active in late summer and much of autumn.

Material studied.

Type material. Primary: USA: North Carolina: Southern Pines, 30.ix.1951, T.B. Mitchell (holotype ♀ [USNM, catalog number: 534046]).

DNA barcoded material with BIN-compliant sequences.

Available. BOLD:ADK0941. Specimens examined and sequenced.-USA: Maryland: Denton (38.9196°N; 75.8273°W) (Caroline County), 19.viii.2012, S. Westre (1♂, BIML).

Non-barcoded material examined.

USA: Texas: Austin (Travis County), 27.x.1981, J.L. Neff (1♀, CTMI); Brackenridge Field Laboratory (Austin, Travis County), 02.xi.1992, J.L. Neff (1♀, CTMI); Brazos County, 24.x.1960, A.H. Alex (1♀, USNM); Dallas, 15.x.??05, F.C. Bishopp (1♀, USNM); Sayersville (Bastrop County), 20.ix.1998, J.L. Neff (1♀, CTMI).