Epeolus tessieris, 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 : 147-149

42. Epeolus tessieris sp. n. Figs 87, 88, 92H

Epeolus cretus Brumley, 1965. M.S. thesis, Utah State University, Logan 42 (♀) [nomen nudum].

Diagnosis.

The following morphological features in combination can be used to tell E. tessieris apart from all other North American Epeolus except E. interruptus : the axilla does not attain the midlength of the mesoscutellum, its tip is unattached to the mesoscutellum for less than 1/3 of the entire medial length of the axilla, and like the mesoscutellum is ferruginous; the mesopleuron has sparser punctures ventrolaterally (most i≥1d) than in upper half, with the interspaces shining; and T1-T4 have medially-interrupted metasomal fasciae. Whereas in E. interruptus the metanotum has a blunt median process and T1 has a wide triangular discal patch with concave lateral sides, in E. tessieris the metanotum is flat and T1 has a trapezoidal to nearly semicircular discal patch.

Description.

FEMALE: Length 5.8 mm; head length 1.7 mm; head width 2.3 mm; fore wing length 4.8 mm.

Integument coloration. Mostly black; notable exceptions as follows: partially to entirely ferruginous on mandible, labrum, antenna, pronotal lobe, tegula, axilla, mesoscutellum, and legs. Mandible with apex darker than rest of mandible; preapical tooth lighter than mandibular apex (difficult to see in holotype because mandible closed; described from paratypes). Antenna brown and orange in part. Pronotal lobe and 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. Dorsum of mesosoma and metasoma with bands of off-white to pale yellow short appressed setae. Mesoscutum with paramedian band. Mesopleuron with upper half hairy, except beneath base of fore wing (hypoepimeral area); ventrolateral half nearly bare. Metanotum with tomentum sparser medially, uniformly off white. T1 with median trapezoidal verging on semicircular black discal patch enclosed by pale tomentum, except for medial separations at base and apex. T2-T4 with fasciae interrupted medially and narrowed before becoming somewhat broader laterally, T2 with fascia with anterolateral extensions of sparser tomentum. T5 with two large patches of pale tomentum anterolateral to and separate from pseudopygidial area. T5 with pseudopygidial area lunate, its apex more 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 much more than 1/4 MOD.

Surface sculpture. Punctures dense, except those of mesopleuron. Labrum with larger punctures than clypeus, but punctures of both equally dense (i≤1d). Small impunctate shiny spot lateral to lateral ocellus. Mesoscutum, mesoscutellum, and axilla coarsely and densely rugose-punctate. Tegula densely punctate (i≤2d). Mesopleuron with denser (i≤1d) punctures in upper half than ventrolateral half (i>1d, largely impunctate areas below line of pale tomentum), the interspaces shining. Metasomal terga with punctures very fine, dense (i≈1d), evenly distributed on disc.

Structure. Preapical tooth blunt and obtuse. Labrum with submedial pair of very small denticles, apex with pair of small points separated by shallow concavity (difficult to see in holotype; described from paratypes). Frontal keel not strongly raised. Scape with greatest length 1.8 × greatest width. F2 noticeably longer than wide (L/W ratio = 1.4). Preoccipital ridge not joining hypostomal carina, from which it is separated by about 1.5 MOD at its terminal. Mesoscutellum moderately 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 not extending beyond midlength of mesoscutellum; axilla with tip visible, but unattached to mesoscutellum for less than 1/3 the medial length of axilla; 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, not noticeably longer than wide (L/W ratio = 1.1); S4 and S5 with much longer coppery to silvery subapical hairs; pygidial plate apically rounded, with large deep punctures closely clustered basomedially and sparser apically and laterally, with the interspaces shining.

Etymology.

This species is named in honor of my wife, biologist Stéphanie Tessier. The name is in the genitive case and declined as mulier, a Latin noun with a consonant stem.

Distribution.

Northern Mexico and bordering U.S. States (Fig. 88).

Ecology.

HOST RECORDS: The host species of E. tessieris is/are presently unknown.

FLORAL RECORDS: Labels of examined voucher specimens indicate floral associations with Cuscuta umbellata Kunth ( Convolvulaceae ), Marshallia Schreb. ( Compositae ), and Pectis papposa .

Discussion.

Of the Epeolus Brumley (1965) identified as new, this appears to be the least commonly collected species. Among examined specimens, there is notable variability in punctation density of the mesopleuron, but the smooth, shiny interspaces are usually greater than puncture diameters. Although BIN-compliant sequences are presently not available for E. tessieris , 421 bp sequences are available for two specimens (a female from Arizona, USA and a male from Coahuila, Mexico), and there is virtually no divergence (<1%) between the two. Moreover, these sequences do not cluster closely with any sequences from other Epeolus species in a NJ tree (Suppl. material 2).

Material studied.

Type material. Primary: USA: Arizona: 3 mi W Marana (Pima County), 13.ix.1962, J.C. Bequaert (holotype ♀, CAS).

Secondary: Mexico: Baja California Sur: Playa El Coyote (26 km SSE Mulegé), 08.ix.1977, E. Fisher and R. Westcott (paratype ♂, CAS); Coahuila: 7 km SE Zapata, 25.viii.1991, J.G. Rozen (paratype ♂, KUNHM).

USA: Arizona: 1 mi E Douglas (Cochise County), 17.viii.1962, M.A. Cazier (paratype ♂, UCBME); 3 mi W Marana (Pima County), 13.ix.1962, J.C. Bequaert (allotype ♂, KUNHM); 4 mi E Willcox (Cochise County), 30.viii.2004, J.G. Rozen and J.S. Ascher (paratype ♀, AMNH); Tucson (Pima County), 27.x.1939, R.H. Crandall (paratype ♀, LACM); New Mexico: 1 mi N Rodeo (Hidalgo County), 22.viii.1964, J.H. Puckle, M.A. Mortenson, and M.A. Cazier (paratype ♂, EMEC); Texas: Kerrville, 31.v.??06, F.C. Pratt (paratype ♀, USNM).

DNA barcoded material with BIN-compliant sequences.

Unavailable.