Acanthocnema Becker, 1894

Sinclair, Bradley J., 2025, Revision of the Nearctic species of Acanthocnema Becker, 1894 (Diptera: Scathophagidae), European Journal of Taxonomy 1026, pp. 304-337 : 306-307

Genus Acanthocnema Becker, 1894

Acanthocnema Becker, 1894: 136 (preocc. Costa, 1859). Name conserved by ICZN (1954: 91).

Clinoceroides Hendel, 1917: 36 . Type species: Cordylura glaucescens Loew, 1864 , by original designation.

Type species

Cordylura nigrimana Zetterstedt, 1846 , by original designation.

Diagnosis

The genus Acanthocnema is characterized by the following combination of characters (modified from Ozerov & Krivosheina 2018): arista short pubescent basally, bare apically; palpus elongate, spatulate, without strong apical / subapical seta; proepisternum with setulae anterior to spiracle; anepisternum covered with setulae along dorsal margin and posteriorly only, without setulae posterior to anterior spiracle; katepisternum with one strong seta in posterodorsal corner; anepimeron bare; postmetacoxal bridge absent; fore femur with or without black spine-like setae ventrally; fore tibia with ventral apical spur, with or without rows of short spinules ventrally; scutellum with a pair of strong apical and a pair of strong basal setae; male sternite 5 usually bilobate posteriorly; ovipositor short and compact, proctiger shifted dorsally bearing long setae; female tergite and sternite 7 fused anteroventrally, tergite 7 subtriangular, strongly tapered and narrowly divided dorsally; female tergite 8 U-shaped, narrowly divided dorsally and encircling proctiger; female sternite 8 divided medially into pair of narrow, tapered lobes.

Eggs

The egg of A. glaucescens was illustrated by Hinton (1981: pl. 129) with the respiratory ridges or horns surrounding the plastron projecting above the jelly-mass of the host eggs.

Larvae

The larval instars of A. glaucescens were described and illustrated by Nelson (1992). The final instar is densely covered in setae, with posterior spiracles surrounded by well-developed lateral tubercles. The mouthhooks have dense and pronounced dentation. The prothoracic spiracles are bicornate with 17 papillae.

Puparium

The puparium was briefly described by Nelson (1992) and photographed by Purcell et al. (2008).