Onycholyda tianmushana Shinohara & Xiao, 2006

Shinohara, Akihiko, Kakuda, Tsuneo, Wei, Meicai & Kameda, Yuichi, 2018, DNA Barcodes Identify the Larvae and Unassociated Male of Three Onycholyda Sawflies (Hymenoptera, Pamphiliidae) from China, Zootaxa 4403 (1), pp. 123-132 : 130

Onycholyda tianmushana Shinohara & Xiao, 2006

( Fig. 4 )

Onycholyda tianmushana Shinohara & Xiao, 2006: 290 ; Shinohara & Wei, 2016: 308.

Distribution. China (Zhejiang, Hunan, Jiangxi).

Host plant. Unknown.

Description of the male: Length about 6.5 mm. Head black: creamy white are whole frontal surface approximately from line just above level of facial crest, and malar space ( Fig. 4C ). Mandible creamy white, brownish at apex; palpi creamy white. Antenna with scape and pedicel creamy white, and apex of pedicel and entire flagellum black. Thorax black, with tegula creamy white. Wings very slightly infuscated; veins and stigma blackish, with very narrow base of stigma pale ( Fig. 4A, B ). Legs creamy white, with coxal bases black and tibiae (except very bases) and tarsi slightly dark brownish. Abdomen black, with 3rd and 4th segments pale orange and broad posterior margins of sterna creamy white.

Head generally similar to other Onycholyda males. Upper frons below ocelli very strongly angularly convex, with shallow but distinct notch medially; ocellar basin deep, triangular in outline, without distinct anterolateral extension; median fovea shallow but distinct; clypeus divided medially by sharply carinate frontoclypeal crest, each half shallowly concave; facial crest very strongly convex and sharply carinate; clypeus with anterior margin not distinctly thickened. Head generally very smooth, almost impunctate; gena very shallowly rugose, punctate and pilose. Left mandible ( Fig. 4D ) bidentate, without median tooth and right one ( Fig. 4E ) tridentate, with incision between apical and median teeth much wider and deeper than incision between median and basal teeth. Left antenna with 27 antennomeres and right one 26 antennomeres; 1 st flagellomere about 1.6× length of 2nd. Subgenital plate with posterior margin subtriangularly produced into narrowly rounded apex. Genitalia normal for the genus, similar to those of O. fulvicornis (see fig. 4 in Shinohara & Wei 2016).

Remarks. Onycholyda tianmushana was described from a female specimen from Xitianmushan, Zhejiang Province (Shinohara & Xiao 2006) and later recorded from Hunan Province and Jiangxi Province also based on female specimens only (Shinohara & Wei 2016). Here we describe the male for the first time.

Based only on the female adult morphology, particularly because of the absence of a middle tooth on the left mandible, Shinohara and Xiao (2006) placed O. tianmushana in the wongi complex of the wongi subgroup of the luteicornis group defined by Shinohara (2002). However, the newly discovered male specimen revealed that O. tianmushana belongs to the amplecta group. The male of O. tianmushana has an entire, high and carinate frontoclypeal crest ( Fig. 4C ), which is characteristic of the species of the amplecta group. Onycholyda tianmushana is the only species of the amplecta group that has a bidentate left mandible ( Fig. 4D ).

Among the Chinese species of the amplecta group, the male of O. tianmushana is similar to that of O. subquadrata (Maa, 1944) in having the head quite smooth and shiny ( Fig. 4C ). Onycholyda tianmushana is a small species (about 6.5 mm) characterized by the bidentate left mandible ( Fig. 4D ), creamy white pale part of the head, and almost entirely blackish stigma and veins C and Sc in the forewing ( Fig. 4A, B ). Onycholyda subquadrata is larger (about 8.5–9.5 mm) and has the left mandible tridentate with a low but distinct median tooth, the pale part of the head pale yellow, and the broad base of the stigma and the veins C and Sc pale yellow. Onycholyda sinica Shinohara, Naito & Huang, 1991 , is also a large species (about 10 mm) having most of the head covered with microsculpture, not very smooth, the left mandible tridentate, the antennal pedicel and flagellum pale brown, and the 2nd and 3rd abdominal terga orange.

Figures

FIGURE 4. Onycholyda tianmushana, male, Kaishan Laodian, Mt. Tianmushan.--- A, Dorsal view; B, ventral view; C, head, frontodorsal view; D, left mandible, dorsal view; E, right mandible dorsal view.A–C, photographed by T. Komatsu.