Euhesma aulaca Hogendoorn & Leijs

Hogendoorn, Katja, Stevens, Mark & Leijs, Remko, 2015, DNA barcoding of euryglossine bees and the description of new species of Euhesma Michener (Hymenoptera, Colletidae, Euryglossinae), ZooKeys 520, pp. 41-59 : 48-51

Taxon classification Animalia Hymenoptera Colletidae

Euhesma aulaca Hogendoorn & Leijs sp. n. Figs 7 A–I, 8 A–E

Material examined.

Holotype: ♀, SAMA 32-033281, Bon Bon Station, South Australia, 30.8440°S, 135.5389°E, 27 October 2010, R Leijs (SAMA). BOLD: AUSBS133-12.

Paratype(male). ♂, SAMA 32-033282, same date and locality as holotype. Paratypes: 3♀, Bon Bon Station, South Australia, 30.7416°S, 135.3665°E, on Eremophila scoparia ; 1♀, Bon Bon Station, South Australia, 30.5250°E, 135.5917°E; 7♀+1♂ in ethanol RL1636 all same date as holotype (SAMA). BOLD: AUSBS131,2,4-12.

Diagnosis.

The species is most like Euhesma yellowdinensis , but the clypeus has a distinctive deep median furrow and the total length of the labial palps is only slightly shorter than the head.

Description.

Female. Length approximately 5.5 mm; wing length approximately 3.5 mm. Head width 1.6 mm. Relative head measurements: width 50; length 50; clypeal length 14; lower interocular distance 28; upper interocular distance 32; interantennal distance 12; antennocular distance 6; interocellar distance 12; ocellocular distance 8. Clypeus with deep median furrow, anterior margin truncate, upper margin indistinct; facial fovae broad, upper part slightly bent towards ocelli; malar space short; labial palp segments increasing in length in the order 1,2,3=4. Clypeus and frons above antennae, interocellar area and scutum with dense reticulation; clypeus and supraclypeal area shining, frons, paraocular areas and scutum dull. Head black; antennae brown with flagella yellowish ventrally; labial palp segments 1 and 2 dark brown, 3 and 4 ribbon-like, yellowish; all femora and tibiae of middle and hind legs medially dark brown, fore tibiae, all tarsi and remaining parts yellow; gaster dark brown. Marginal zones of metasoma wide and translucent. Forewing with first recurrent vein almost interstitial with first submarginal crossvein. Scattered long white hairs on frons, clypeus, antennal scapes, vertex, mandibles, posterior genae, sides of thorax, venter and gastral tergum 5, pygidial fimbria pale orange.

Male. Length approximately 5.2 mm; wing length approximately 3.6 mm. Head width 1.2 mm. Relative head measurements: width 50; length 60, clypeal length 17; lower interocular distance 22; upper interocular distance 30; interantennal distance 8; antennocular distance 5; interocellar distance 12; ocellocular distance 9. Forewings, labial palps and other characters as in female; inner hind tibial spur roughly pectinate; Terminalia as in Fig. 8 A–E.

Remarks.

Exley (1998) distinguishes the species from group 1 (the alicia species group) from those of groups 2 and 3 on the basis of the length of the labial palps, which are substantially shorter than the head in the species of group 1, and longer than the head in groups 2 and 3. Although the labial palps of female Euhesma aulaca are shorter than the head, the difference in length is only slight, while the shape and length of the labial palp segments are like other species in the alicia species group. Based on molecular and morphological data, Euhesma aulaca has been classified in the alicia species group, and the first couplet of the key has been modified to include this species.

Etymology.

The specific name means 'with a furrow’, referring to the deep median furrow in the clypeus.