Lasioglossum (Lasioglossum) haesitans (Blüthgen, 1931)

Halictus haesitans Blüthgen, 1931: 348, ♂. Holotype: ♂, Russia: “Temir-chan-schura” (Dagestan); ZISP. Published data. Blüthgen 1931: 348 (Dagestan Republic); Pesenko 1986: 123 (Dagestan Republic, as L. korbi).

Material examined. RUSSIA. Chechen Republic: 1 ♂, Paraboch, 13.VII.1927, Kirichenko; Dagestan Republic: 1 ♂, 22 km SW of Terekli-Mekteb, 44°04′N 45°64′E, 21.VI.2018, MP, VL, MM ; 2 ♂, 20 km W of Makhachkala, Sarykum, 43°00′N 47°14′E, 28, 29. V.2019, MP, VL ; 2 ♂, Kumtorkala, near Barkhan Sarykum, 43°002′N 47°237′E, 31.V.2019, MM, KF ; 1 ♂, 5 km NW of Talgi, 42°52′N 47°26′E, 25. VI.2018, KF ; 1 ♂, idem, 31.05.2019, MP, VL .

Distribution. Russia (North Caucasus); Greece, Azerbaijan, Turkey.

Remarks. Blüthgen (1931: 348) described Lasioglossum haesitans from a male and suggested the possible synonymy of this species with L. korbi (Blüthgen, 1929) because of the more likely association of the male of L. haesitans with female of L. korbi . Later L. haesitans was considered as a junior synonym of L. korbi (Pesenko 1986; Astafurova & Proshchalykin 2017a, 2018). Ebmer (2014: 347) restored L. haesitans as a valid species. Ebmer does not give a diagnosis or description of the female, but noted on misidentification with L. quadrinotatum in published data. A female of L. haesitans from Greece was illustrated in Pauly (2016). The correct identification of the species can only be done by the male, which differs from L. quadrinotatum by entirely black clypeus or only narrowly apical strip (vs wide yellow spot in L. quadrinotatum) and longer gonostylus, distinctly longer than wide (Fig. 9, vs about as long as wide in L. quadrinotatum, Fig. 10). The records of Lasioglossum korbi in Azerbaijan by Pesenko (1986) and Astafurova et al. (2024a) refer to L. haesitans . Thus, L. korbi is known only from Turkey.