Pylaemenes Stål, 1875: 51, 93 (= Datames Stål, 1875; = Pyloemenes Bradley & Galil, 1977). Type-species: Phasma (Pachymorpha) coronatum Haan, 1842: 137, pl. 14, figs 4–5 (= Pylaemenes coronatus), by subsequent designation of Kirby, 1904: 400.
Diagnosis. Medium to large Dataminae. Apterous. Body robust and thick-built. Head oval. Occiput of head conically elevated with a short crest. Antennae distinctly longer than profemora, surpassing apices of protibiae. Scapus with short tubercles on outer edge. Pronotum nearly square or trapezoidal. Mesonotum rectangular or trapezoidal, more than twice as long as pronotum, carinate medially. Metanotum longer than wide or as long as wide, longer than median segment. Abdomen cylindrical or subcylindrical in female, cylindrical in male. Seventh sternum with or without praeopercular organ on posterior area in female. Cerci flattened, small and short. Profemora indistinctly curved basally. Anterodorsal and posterodorsal carinae of mesofemora and metafemora with small blunt teeth. Anteroventral and posteroventral carinae of mesofemora and metafemora with or lacking blunt teeth near apices.
Distribution. China, Indonesia, Japan, Malaysia, Singapore, Thailand, Vietnam.
Remarks. Currently, four species of Pylaemenes are recognized in Vietnam. A key to the females of the genus is provided. The female of P. abramovi sp. nov. is unknown and not sufficiently provided in the key. A key to the males of the genus is not provided because the males of P. konkakinhensis sp. nov. and P. guangxiensis (Bi & Li, 1994) are unknown.
Key to females of Pylaemenes Stål, 1875 from Vietnam.
1. Posteromedial area of seventh abdominal sternum lacking praeopercular organ.......................................................... P. guangxiensis
Posteromedial area of seventh abdominal sternum with a hump-like praeopercular organ..................................................................2 2. Scapus of antennae with a short tubercle on outer edge........................................................................... P. konchurangensis sp. nov.
Scapus of antennae with two short tubercles on outer edge........................................................................ P. konkakinhensis sp. nov.