Lentocerus lijiangensis Dong & Naito 1999

Broad, Gavin R., 2021, Taxonomic changes in Ichneumonoidea (Hymenoptera), and notes on certain type specimens, Zootaxa 4941 (4), pp. 511-541 : 529-531

Lentocerus lijiangensis Dong & Naito 1999

Current combination. junior synonym of Euceros sensibus Uchida 1930 , new synonymy ( Ichneumonidae : Eucerotinae ).

Material examined. Lentocerus dentatus Dong & Naito 1999 ♂ holotype, ISAS, China, Yunnan, Lijiang , 2,915 m a.s.l., 15.vi.1996, coll. Dong Dazhi; Lentocerus lijiangensis Dong & Naito 1999 ♂ holotype [published as ♀], ISAS, China, Yunnan, Lijiang , 2,915 m a.s.l., 15.vi.1996, coll. Dong Dazhi.

Comments. Dong & Naito (1999) described a striking new genus of Cryptinae (as Gelinae) from China, Yunnan Province, based on two specimens representing two species. Although the authors placed this genus, Lentocerus Dong & Naito 1999 , in the Cryptini subtribe Sphecophagina , they were unaware of the genus Euceros Gravenhorst , which comprises one of two genera of the subfamily Eucerotinae ( Gauld & Wahl 2002) . The strikingly modified antennal flagellum, proposed by Dong & Naito as a unique feature of their new genus, is a notable apomorphy of males of many species of Euceros , which otherwise look rather unremarkable, being stout ichneumonids with a broad first metasomal tergite, superficially resembling Sphecophaga Westwood in general morphology and wing venation, hence the confusion regarding classification of these specimens. A unique feature of Euceros , that is often difficult to see on specimens when the head is not tilted correctly, is the bilobed process on the dorsum of the pronotum. Thanks to Prof. Mao-Ling Sheng, I was able to examine photographs of the holotypes of both Lentocerus dentatus Dong & Naito and L. lijiangensis Dong & Naito and could confirm that these are indeed specimens of Euceros . Both species are synonymised here with described species of Euceros .

The extremely modified male antennae (the central flagellomeres with tooth-like expansions on each side) and the colour pattern (mesosoma with several yellow markings and metasoma with pale posterior bands on first to fourth tergites) firmly place Lentocerus dentatus as a junior synonym of Euceros pruinosus . Often relatively common, E. pruinosus has been recorded across the Palaearctic from Britain and Spain in the west to Japan and Russia (Kamchatka) in the East, but this is the first record for China (from Yunnan Province).

Lentocerus lijiangensis fits Barron’s (1978) redescription of E. sensibus very well and matches a specimen identified as this species, from Nepal, in NHMUK. Contrary to Dong & Naito (1999) the holotype of Lentocerus lijiangensis is a male, not a female (the tiny ovipositor of eucerotines can easily be mistaken for an aedeagus). The male antennae are highly modified and the colour pattern, especially the conspicuous ferruginous spots apicolaterally on tergites 1–3, is distinctive. The face is mostly yellow, at the paler end of the spectrum of variation as described by Barron (1978). Previously recorded from Japan, Korea, Nepal, Russia and Taiwan, this is the first record of E. sensibus from mainland China (from Yunnan Province).