Epeolus gibbsi, Onuferko, Thomas M., 2018

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 : 84-86

24. Epeolus gibbsi sp. n. Figs 3D, 51, 52, 96C, 97F

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. gibbsi apart from all other North American Epeolus : the mandible has a blunt, obtuse preapical tooth; in females, F2 is less than 1.2 × as long as wide; the axilla does not attain the midlength of the mesoscutellum but the free portion is distinctly hooked, with the tip unattached to the mesoscutellum for more than 1/3 of the entire medial length of the axilla; the mesopleuron is closely and evenly punctate (i≤1d), with the interspaces shining and punctures similar in size; the legs are usually darker, at least from the metacoxa to metatibia; the metasomal terga have rather fine punctures; S4 and S5 of the male have long curved coppery to silvery subapical hairs; and the pseudopygidial area of the female is distinctly campanulate with the apex <2 × the medial length and in contact with two large patches of pale tomentum (one on each side [the two are parallel to each other]) throughout its length. Epeolus gibbsi most closely resembles E. ilicis and E. inornatus , but in males of the latter S4 and S5 have short straight subapical hairs and in both E. ilicis and E. inornatus the mandible is simple, and in females of both species F2 is more than 1.2 × as long as wide and the pseudopygidial area is not in contact with two large patches of pale tomentum (one on each side) throughout its length (in contact only at apex, diverging basally).

Description.

FEMALE: Length 7.3 mm; head length 1.9 mm; head width 2.5 mm; fore wing length 5.8 mm.

Integument coloration. Mostly black; notable exceptions as follows: partially to entirely ferruginous on mandible, antenna, pronotal lobe, tegula, and legs. Mandible with apex darker than all but extreme base; preapical tooth lighter than mandibular apex (difficult to see in holotype; described from paratype). Antenna dark brown except scape and F1 reddish brown in part. Pronotal lobe dark brown to black. Tegula pale ferruginous to amber. Wing membrane subhyaline, apically dusky. Legs more extensively reddish orange than brown or black.

Pubescence. Face with tomentum densest around antennal socket. Tomentum slightly sparser on 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 densely hairy, except for two sparsely hairy circular patches (one behind pronotal lobe, a larger one occupying much of ventrolateral half of mesopleuron). Metanotum with tomentum uninterrupted except for median bare patch in posterior half, uniformly off white. T1 with median elliptical verging on semicircular discal patch. T1 and T2 with apical fasciae interrupted medially, those of T2 and T3 somewhat broader laterally, T2 with fascia with anterolateral extensions of sparser tomentum. T3 and T4 with fasciae complete. T5 with two large patches of pale tomentum parallel to and contacting pseudopygidial area throughout its length. T5 with pseudopygidial area campanulate, 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 extending beyond apex of sternum by ~1/3 MOD.

Surface sculpture. Punctures dense. Labrum with larger punctures than clypeus, but punctures of both equally dense (i<1d). Impunctate spot lateral to lateral ocellus absent in holotype, but shiny spot present in some paratypes. Mesoscutum, mesoscutellum, and axilla coarsely and densely rugose-punctate. Tegula densely punctate (i≤2d). Mesopleuron with ventrolateral half densely punctate (i≤1d), the interspaces shining; mesopleuron with punctures similar in size and more or less equally dense throughout. Metasomal terga with punctures very fine, dense (i=1-2d), evenly distributed on disc; the interspaces shining somewhat.

Structure. Preapical tooth blunt and obtuse. Labrum with pair of small subapical denticles not preceded by carinae. Frontal keel not strongly raised. Scape with greatest length 1.8 × greatest width. F2 not noticeably longer than wide (L/W ratio = 1.1). Preoccipital ridge not joining hypostomal carina, from which it is separated by about 1 MOD at its terminal (difficult to see in holotype; described from paratype). Mesoscutellum strongly bigibbous. Axilla small to intermediate in size, its lateral margin (L) less than half as long as mesoscutellar width (W) (L/W ratio = 0.4) and tip attaining midlength of mesoscutellum; axilla with tip conspicuously diverging from side of mesoscutellum, distinctly hooked, and axilla with free portion 2/5 its medial length; axilla with lateral margin relatively straight and without carina. 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, as long as wide (L/W ratio = 1.0); S4 and S5 with much longer coppery to silvery subapical hairs; pygidial plate apically rounded, with large deep punctures closely clustered.

Etymology.

This species is named after its discoverer, Prof. Jason Gibbs, who collected the specimen herein designated as the holotype, recognized it as an unusual find, and brought his discovery to my attention.

Distribution.

Upper midwest and adjacent Canada (Fig. 52).

Ecology.

HOST RECORDS: The holotype of E. gibbsi was collected in an area where Colletes brevicornis and C. kincaidii were in abundance, the latter of which is likely associated with E. minimus , which was also present at the site, as was E. ainsliei and its tentative host C. susannae (J. Gibbs, personal communication, 2017).

FLORAL RECORDS: Unknown.

Discussion.

What Romankova (2004) identified as E. ilicis , which constituted a new record of that species in Canada, might actually be E. gibbsi and/or E. inornatus . Unfortunately, the vouchered material from that study (three specimens from Ontario) cannot be traced, so the presence of E. ilicis in Canada has not been confirmed in the present study. Epeolus ilicis has been reported from the New England states, though the only examined specimen from that region (a male from Massachusetts) that has been identified as E. ilicis (by Richard L. Brumley) appears to actually be E. inornatus based on the very short straight subapical hairs on S4 and S5. In Canada, E. gibbsi is only confirmed from southern Manitoba, so the specimens from southern Ontario studied by Romankova could represent any of the three species. The key presented in Onuferko (2017) still works for E. ilicis , but can also lead to E. gibbsi and E. inornatus with the modifications presented in Suppl. material 3 starting at couplet 4. Presently, only a single 422 bp sequence is available for E. ilicis (a male specimen from Florida, USA), which clusters with sequences of E. zonatus (Suppl. material 2), and all were assigned the same BIN. In addition to the diagnostic morphological features that separate E. gibbsi from other similar species (notably E. erigeronis , E. ilicis , and E. inornatus , for which only partial sequences 394 to 422 bp in length are available), the status of E. gibbsi as a separate species is supported by a separate BIN and large barcode sequence divergence (4.7%) from its nearest neighbor, E. glabratus . Based on the few known records, adults of E. gibbsi appear to be active in late spring/early summer.

Material studied.

Type material. Primary: Canada: Manitoba: Spruce Woods Provincial Park (49.6630°N; 99.2790°W) (Spirit Sands, Division 7), 07.vii.2017, J. Gibbs and Nozoe (holotype ♀ [CCDB-30345 D02], JBWM).

Secondary: USA: Wisconsin: Two Rivers, 26.vi.1911 (allotype ♂, CUM), 26.vi.1911 (paratypes 1♀, 6♂, CUM).

DNA barcoded material with BIN-compliant sequences.

Available. BOLD:ADI6791. See Type material for specimens examined and sequenced (indicated by unique CCDB-plate and well number).