Lasioglossum (Hemihalictus) adabaschum ( Blüthgen, 1931 )

Astafurova, Yu. V. & Proshchalykin, M. Yu., 2023, First record of Lasioglossum adabaschum (Blüthgen, 1931) (Hymenoptera: Halictidae) from Europe with description of hitherto unknown male, Far Eastern Entomologist 479, pp. 1-6 : 2-5

Lasioglossum (Hemihalictus) adabaschum ( Blüthgen, 1931)

Figs 2–10

Halictus adabaschum Blüthgen, 1931: 368, fig. 12a, ♀ (holotype: ♀, Ashgabat, Turkmenistan, 5.V.1928, V. Gussakovskij; ZISP), examined .

MATERIAL EXAMINED. Russia: Astrakhan Province, Volzhskiy, 46°58' N, 47°32' E, 24.VII 2017, 3 ♀, 1 ♂, M. Mokrousov; Kalmyk Republic, 23 km SEE Khulkhuta, Davsna Sands , 46°17' N 46°40' E, 15-16.VII.2015, 1 ♀, M. Proshchalykin, V . Loktionov, M. Mokrousov; 16 km E of Khulkhuta , 46°17' N 46°41', 29. V 2016, 3 ♀, Yu. Astafurova [ ZISP] .

DIAGNOSIS. Pesenko (2007: 23) considered this species a member of the Lasioglossum punctatissimum species group into the subgenus Puncthalictus Warncke, 1975 . However L. adabaschum has the long dorsal surface of propodeum (as long as scutellum), the granulate (at list on upper half) mesepisternum (Figs 5, 6) and the relatively long malar space. In this features L. adabaschum is rather closest to L. pallidum (Radoszkowski, 1888) and in addition both have a head higher than wide, short male antennae, a inner metatibial spur with 3–4 relatively long truncate teeth (Fig. 4), similar form of gonostylus with elongate membranous lobe and similar structure/sculpture of the body. Lasioglossum adabaschum can be easily distinguished from L. pallidum by the mostly black body (versus almost entirely ochre- or whitish-yellow).

DESCRIPTION OF HITHERTO UNKNOWN MALE. Sructure and sculpture. Total body length 5.5 mm. Head (Figs 2, 3) elliptic, 1.12 times as long as wide; vertex not elevated, distance from top of head to upper margin of lateral ocellus ca. 0.3 lateral ocellar diameter as seen in frontal view. Clypeus 1.25 times wider than high; on lower third almost impunctate, with a few tiny punctures, on upper two thirds densely and finely (10–15 μm) punctate with punctures separated by 1–2 puncture diameters, interspaces polished and shiny. Supraclypeal area polished, irregularly and finely punctate (5–10 μm / 1–4). Frons and vertex with tiny punctures (5–10 μm) separated less than a puncture diameter. Genal area expanded downward, 0.75 times as wide as eye in lateral view, finely punctate with smooth interspaces (sculpture scarcely visible under denser pubescence). Antennae short, not reaching scutellum, F1 transverse, 0.8 times as long as wide, F2 1.35 times as long as wide, remaining flagellomeres ca. 1.15 times as long as wide. Mesepisternum with confluent

Figs 2–10. Lasioglossum adabaschum (Blüthgen) : 2, 3, 5, 7–10 – ♂ (2, 3 – head, frontal (2) and lateral (3) views; 5 – mesepisternum, dorsal view; 7 – metasoma, dorsal view; 8 – mesosoma, dorsal view; 9, 10 – genitalia, lateral (9) and dorsal (10) views); 4, 6 – ♀ (4 – inner metatibial spur, lateral view; 6 – mesepisternum, dorsal view). Scale bars: 0.5 mm (2, 3, 7, 8); 0.3 mm (4–6, 9, 10).

and tiny punctures (granulose) on upper half, on lower part with smooth and shiny interspaces ca. a puncture diameter (Fig. 5). Mesoscutum and mesoscutellum polished and shiny, medially finely and relatively sparse punctate (10–12 μm / 2–4), peripherally denser with punctures separated by ca. a puncture diameter (Fig. 8). Posterior vertical surface of propodeum without lateral carina in upper half; propodeum long, its dorsal surface as long as scutellum, flat, horizontal; metapostnotum shiny, with rugulose sculpture not reaching posterior margin, smother along its posterior margin (Fig. 8). Lateral and posterior surface of propodeum shagreened. Metasoma elongate elliptical, with maximum width at level of T 3 (Fig. 7). Terga smooth, densely and distinctly punctate (ca.10 μm / 0.5–3); posterior areas (marginal zones) depressed only laterally, on T 2– T 4 finely transversely lineolate (tessellate). Sterna finely transversely lineolate (tessellate). Gonostylus small (Fig. 10), membranous lobe long, expanded basally and pointed apically (Fig. 9).

Coloration. Body mostly black, but clypeus on lower third, labrum and mandibles yellow; antennae on upper side dark brown, on lower side ochre-yellow. Femur, tibia and tarsi yellow-red (amber). Wings hyaline with light yellow veins and stigma. Terga brownish with amber, posterior areas translucent, yellowish. Sterna amber with yellowish posterior areas. Pubescence. Whitish. Face, gena, lateral part of mesosoma with denser obscuring the integument pubescence. Mesoscutum with sparser tiny setae with but along margins with dense thick plumose setae. Metanotum with tomentum obscuring the integument. Terga with anterior bands of tomentum well visible under truculent posterior margins; T 1 with lateral spots of relatively dense tomentum. Sterna with long erect setae along posterior margins.

DISTRIBUTION. Turkmenistan (Ashgabat), Russia (Astrakhan Province, Kalmyk Republic) (new record).