Acerocnema Becker 1894

Genus Acerocnema Becker, 1894 Acerocnema Becker, 1894: 154. Type species, Cordylura breviseta Zetterstedt (original designation). Pachystyla Lioy, 1864: 1005. Type species, Cordylura macrocera Meigen (original designation). Preoccupied by Pachystyla Mörch, 1852 (Mollusca). Diagnosis. Small-bodied flies around 3.0–6.0 mm in length; arista bare or short pubescent, not exceeding the maximum length of the postpedicel in male; palpus basally slender and spatula-shaped apically, without strong apical or subapical seta; proboscis slender with reduced labella; setae whitish yellow or black on head and body; thorax yellow to black and shiny, covered with microtrichia; proepisternum covered with setulae at middle or in anterior part; anepisternum covered with setulae along dorsal margin and on posterior part only, without setulae posterior to anterior spiracle; katepisternum with one strong seta on posterodorsal corner; scutellum with strong setae; vein R 1 usually bare or with setulae on apical portion; CuA+CuP not reaching wing margin; legs slender without black or strong setae; abdomen with fine setae over surface; male sternite V usually strongly bilobate posteriorly, surstylus slender and flattened with various shapes, sometimes enlarged apically; cerci well developed and divided with multiple sections; female abdomen segments beyond VI compressed; ovipositor short, strongly sclerotized.