The taxonomic accounts of the genus Symmorphus Wesmael (Hymenoptera, Vespidae, Eumeninae) from China, with descriptions of three new species

Abstract In this study, we recognize and review a total of 19 species of the genus Symmorphus Wesmael from China. We also provide a key to these species. Three new species are described and illustrated, namely Symmorphus (Symmorphus) tianchiensis Li & Chen, sp. n., S. (S.) cavatus Li & Chen, sp. n., and S. (S.) nigriclypeus Li & Chen, sp. n. The following four species are newly recorded from China: Symmorphus (S.) fuscipes (Herrich-Schaeffer), S. (S.) lucens (Kostylev), S. (S.) sublaevis Kostylev, and S. (S.) violaceipennis Giordani Soika. In addition, we map the species geographical distributions in China of these 19 species. Type specimens of these three new species are deposited in Chongqing Normal University and Yunnan Agricultural University.


Materials and methods
The specimens examined are deposited in the Institute of Entomology and Molecular Biology, Chongqing Normal University, Chongqing, China (CQNU) and Department of Entomology, College of Plant Protection, Yunnan Agricultural University, Kunming (YNAU), respectively. Descriptions and measurements were made under a stereomicroscope (Nikon SMZ1500), and all figures were taken with a stereomicroscope (LEICA EZ4HD) attached to a computer using Leica Application Suite version 2.1.0 software. The ratios used throughout the descriptions were measured in the same amplifying multiple of stereomicroscope. All measurements were taken as the maximal length of body parts measured. Body length was measured from the anterior margin of head to the posterior margin of metasomal tergum 2. For the density description of punctures, the phrase widely spaced means that the intervals between are larger than diameter, moderately spaced means equal to diameter, and whereas closedly spaced means less than diameter. The abbreviations used in the text are shown as follows: T1 for metasomal tergum 1, T2 for metasomal tergum 2, S1 for metasomal sternum 1, S2 for metasomal sternum 2, and so on. Terminology principally follows Carpenter (1982) and Cumming and van der Vecht (1986).
Distribution. China (Yunnan). Remarks. This species is similar to S. (S.) sichuanensis by S1 without basal carina, T1 with transverse carina laterally faint to obsolete, and mesepisternum with epicnemial carina dorsally obsolete; but can be easily distinguished from the similar species and other members of the genus by the combination of the following characters: body moderately long; in both female and male, dorsal pronotal spot orange-red (Figs 1, 5); in female, mesepisternum with epicnemial carina ventrally faint; in male, antenna without tyloids (Fig. 2), and subapical border of both T2 and S2 orange-red.
Etymology. It is named after the type locality of the species, Tianchi National Nature Reserve in Dali city, Yunnan of China. Description. Female ( Fig. 11): body length 6.5 mm, forewing length 7.0 mm. Black; with the following parts pale brown: basal transverse band of clypeus, post-ocular dot, medially uninterrupted dorsal pronotal band, large dorsal mesepisternal spot, tegula, large mesoscutellar spot apically, apex of T1, apical margin of both T2 and S2, apex of fore femur, and fore tibia largely; fore and mid tarsi dark brown. Wings lightly infuscate. Hairs pale brown, mesosoma without sparse lengthened hairs, in addition to short pubescence.
Remarks. This species is easily distinguished at once from all other species of Symmorphus by the combination of the following characters: propodeal posterior face deeply hollowed (Fig. 16), and occipital carina with 2 submedial incisions, in other species of the genus propodeal posterior face not hollowed.
Female. Unknown. Remarks. This species is easily distinguished from all other species of Symmorphus by the combination of the following characters: body black, except apical margin of T1, and subapical margins of both T2 and S2 (Fig. 17); clypeal apex deeply emarginated and with acute apical toothed laterally (Fig. 18).