Lasioglossum (Dialictus) submandibulare Niu, 2020

Niu, Zeqing, Zhang, Dan & Zhu, Chaodong, 2020, Extraordinary bees of the genus Lasioglossum Curtis, 1833 (Hymenoptera: Apoidea: Halictidae) from China, Zoological Systematics 45 (1), pp. 50-58 : 54-56

publication ID	https://doi.org/ 10.11865/zs.202005
publication LSID	lsid:zoobank.org:pub:DDB1E5B8-2D81-461D-9C0F-F3BE928E0408
DOI	https://doi.org/10.5281/zenodo.4617900
persistent identifier	https://treatment.plazi.org/id/A74387EC-FF8C-FFD9-2A98-F8BD77B13E02
treatment provided by	Carolina
scientific name	Lasioglossum (Dialictus) submandibulare Niu
status	sp. nov.

Treatment

Lasioglossum (Dialictus) submandibulare Niu , sp. nov. ( Figs 4–5 View Figure 4 View Figure 5 )

Type material. Holotype, female, China, Sichuan, Mao Xian (31º43′N, 103º55′E), 25.V.2011, leg. Zeqing Niu. GoogleMaps

Etymology. The specific name means the new species is very similar to Lasioglossum mandibulare ( Morawitz, 1866) .

Diagnosis. According to the current subgeneric classification of the genus Lasioglossum ( Gibbs, 2010) , the new species belongs to the subgenus Dialictus . The extraordinary and amazing characters of the new species is its elongated mandible ( Fig. 4C View Figure 4 ) and strongly raised pronotum ( Fig. 4G View Figure 4 ). The new species is very similar to L. mandibulare ( Morawitz, 1866) by its elongated mandible. Comparing with the type species of L. mandibulare ( Morawitz, 1866) (Astafurova & Proshchalykin, 2018) , the species has following characters: head and mesosoma with blue-green metallic reflections; antennal flagellum blackish-brown ( Fig. 4A View Figure 4 ); mandible dark brown ( Fig. 4C View Figure 4 ); all tibiae and tarsi brown ( Fig. 5A View Figure 5 ); punctures on clypeus and supraclypeal area sparser; the dorsolateral angle of pronotum triangle, right-angle apically ( Fig. 4D View Figure 4 ); lateral slope of propodeum smooth, without fine striate ( Fig. 4E View Figure 4 ). Meanwhile, L. mandibulare ( Morawitz, 1866) is characterized by: head and mesosoma black, without metallic reflections; antennal flagellum yellowish-brown; mandible yellow; all tarsi yellowishbrown; lateral slope of propodeum with fine striae.

The new species is also similar to L. pronotale Ebmer, 2002 by the strongly raised pronotum, but has the head as broad as long, nearly quadrate in frontal view, while the head of L. pronotale is longer than broad, longitudinal rectangular in frontal view.

Description. Female. BL 7.0 mm ( Fig. 5A View Figure 5 ); head quadrate in frontal view, nearly as broad as long, HW: HL = 48: 47 ( Fig. 5B View Figure 5 ); vertex long, ocelloccipital distance long, about 4 times as long as the lateral ocellus diameter ( Fig. 4A View Figure 4 ); gena obviously broader than eye, GW: EW = 19: 9 ( Fig. 4B View Figure 4 ). Clypeus rectangle, nearly 3 times as broad as long, apical margin truncate ( Fig. 4C View Figure 4 ); mandible elongate, with single preapical tooth ( Fig. 4C View Figure 4 ); forewing with three submarginal cells, 1st equal in length to 2nd and 3rd combined, distal veins (1rs-m, 2rs-m, 2m-cu and distal abscissae of M) weak, marginal cell pointed on anterior margin of wing ( Fig. 5B View Figure 5 ); dorsolateral angle of pronotum triangle, right-angle shaped apically ( Fig. 4D View Figure 4 ), pronotum strongly convex toward to the dorsum ( Fig. 4G View Figure 4 ); propodeal dorsum as long as scutellum, nearly flat, with very fine striae not reaching posterior margin of propodeal dorsum ( Fig. 4E View Figure 4 ); lateral slope of propodeum smooth, without fine striae ( Fig. 4E View Figure 4 ), posterior vertical surface of propodeum carinate along lateral margin, but the carina ill-developed, only up to 2/3 of the lateral margin, lateral carina and transverse carina absent ( Fig. 4E View Figure 4 ); hind basitibial plate present, enclosed by carina; inner hind tibial spur pectinate with two large teeth ( Fig. 4H View Figure 4 ). Clypeus nearly polished, only with a few scattered punctures ( Fig. 4C View Figure 4 ); supraclypeal area very sparsely punctate, i=3–5d ( Fig. 4C View Figure 4 ); paraocular area and frons very densely and finely punctate, i=0.2–1.0d ( Fig. 4C View Figure 4 ); vertex very sparsely punctate, i=5–6d ( Fig. 4A View Figure 4 ); scutellum sparsely punctate, i=1–3d ( Fig. 4D View Figure 4 ); T 1 polished, without punctures ( Fig. 4F View Figure 4 ). Head, mesosoma with blue-green metallic reflections, metasomal terga dull reddish-brown, without metallic reflections ( Figs 4F View Figure 4 , 5A View Figure 5 ); mandible dull reddish-brown ( Fig. 4C View Figure 4 ); antenna blackishbrown except flagellum with ventral surface lighter, brown ( Fig. 4A View Figure 4 ); forewing subhyaline with brownish-yellow veins and stigma except R vein brown ( Fig. 5B View Figure 5 ); legs dark brown ( Figs 4H View Figure 4 , 5A View Figure 5 ). Clypeus, lower part of paraocular area, vertex, and mesosoma covered sparse dirty-yellowish pubescence. T 2– T 3 with basal whitish tomentum ( Fig. 4F View Figure 4 ). Hind femur and tibia with yellowish plumose hairs forming the scopa ( Fig. 4H View Figure 4 ).

Male. Unknown.

Distribution. China (Sichuan).

Floral association. No information.

Funding This work was financially supported mainly by the National Natural Science Foundation of China (31772487) to Zeqing Niu, the grant (Y229YX5105) from Key Laboratory of Zoological Systematics and Evolution, Chinese Academy of Sciences. Chaodong Zhu acknowledges the supports of the National Science Fund for Distinguished Young Scholars (31625024) and Singapore-China Joint Research Grant (41761144068).

Acknowledgements The authors would like to express their sincere thanks to Dr. Alain Pauly for his assistance in identification of Lasioglossum longirostre , also to Dr. Jason Gibbs, and two anonymous reviewers for their comments and suggestions to streamline and improve the earlier drafts of the manuscript.