Megachile viridicollis Morawitz, 1875

Praz, Christophe J. & Benon, Dimitri, 2023, Revision of the leachella group of Megachile subgenus Eutricharaea in the Western Palaearctic (Hymenoptera, Apoidea, Megachilidae): A renewed plea for DNA barcoding type material, Journal of Hymenoptera Research 95, pp. 143-198 : 143

Megachile viridicollis Morawitz, 1875

Figs 67-70

Megachile viridicollis Morawitz, 1875: 117, ♂, “поймать только раз в степи Кизиль кумъ 15 мая у восточной окрайны горы Каракъ [Caught only once in the steppe of Kyzyl Kum, the 15. May, at the eastern edge of the mountain Karak; Kyzyl Kum does not refer to the Kyzyl Kum Desert, but probably to the locality Қызылқұм, approx. 41.911N 67.988E, Kazakhstan]".

Material examined.

Type material. We were not able to examine the type material of M. viridicollis . The placement of this species into the Megachile concinna complex is based on the original description, which mentions that the species is highly similar to " M. argentata " (either M. pilidens or M. leachella ), but markedly larger, and with a conspicuous tooth at the base of the mandible. We interpret this tooth as the tooth present just behind the base of the mandible (as in Fig. 12 ). We also examined one male specimen identified as M. viridicollis from " Baigakum bei Djulek Turkest. [ Kazakhstan: Baygekum, Zholek; approx. 44.314 N 66.475 E]", identified by L. Wollmann (who possibly had access to material identified as M. viridicollis by Morawitz) and perfectly agreeing with the original description of M. viridicollis . Baygekum is located approximately 200 km NE of the type locality of M. viridicollis .

Other material.

Eight specimens from Kazakhstan and Uzbekistan (Suppl. material 1).

Description.

The following description is based on one male specimen from Baygekum and several female specimens from Gazli, Uzbekistan, presumed to be conspecific.

Male: Member of the Megachile concinna complex, as determined by the presence of the tooth behind the mandibular base and the apically simple genitalia. OOD as in European populations of M. anatolica (as in Fig. 11 ), thus nearly as long as interocellar distance. Vestiture particularly long and dense, in particular tergal fasciae thicker and longer. Larger than all other species of the Megachile concinna -complex (body length 10 mm).

Female: similar to M. anatolica , differs from that species in the following characteristics: larger (body length 11 mm). Vertex laterally covered with short, brownish hairs, so that integument is not visible under vestiture unless the hairs are removed (Fig. 70 ); punctation dense and fine (Fig. 70 ). Clypeus apically without teeth, broadly emarginated (as in M. pilidens ) but with a conspicuous, rounded, thickened margin, medially with a small tooth (Fig. 69 ). Metasoma with snow white vestiture forming particularly dense tergal fasciae and entirely covering the base of T6. Punctation of disc of T4 sparse (Fig. 68 ), similar to European populations of M. anatolica (Fig. 8 ).

Distribution.

So far known only from few specimens from Kazakhstan and Uzbekistan.

Geographic variation and note.

The identity of this taxon remains unclear, as very little material has been studied. Soltani et al. (2017) presented sequence data for two populations, one based on several male specimens from the region of Khiva, Uzbekistan (41.33N, 60.35E and 41.36N, 60.35E), and one based on several female specimens from Gazli, Uzbekistan (40.383N, 63.100E); these two populations were genetically strongly divergent (4.1 %). The male specimens from the Khiva region are markedly smaller than the male examined from Baygekum (see above), while the females from Gazli are particularly large for the Megachile concinna complex. It is possible that the populations from Khiva represent transitional populations to M. anatolica . Additional research including more material from Central Asia is needed to better delineate this species. Megachile viridicollis and M. anatolica are genetically closely related, and both may be treated as conspecific, in which case the name M. viridicollis would have priority. The striking differences in female morphology lead us to treat both taxa are distinct species.

Figures

Figures 67 - 70. Megachile viridicollis 67 female metasoma 68 female metasomal tergum 4 69 apex of female clypeus 70 female vertex.

Figures 7 - 14. Megachile anatolica 7 female metasoma 8 female metasomal tergum 4 9 female vertex 10 apex of female clypeus 11 dorsal view of head of holotype male 12 front view of male head with distinct tooth behind mandibular base 13 male metasomal sterna 3 - 5 14 male genitalia.