Pseudohercostomus Stackelberg, 1931

Grootaert, Patrick & Velde, Isabella Van de, 2021, Understanding the tangled taxonomy of the genus Pseudohercostomus Stackelberg, 1931 (Insecta: Diptera: Dolichopodidae) with description of new species from Singapore and DR Congo, Raffles Bulletin of Zoology 69, pp. 324-335 : 325

Pseudohercostomus Stackelberg, 1931

Pseudohercostomus Stackelberg, 1931: 776 . Type species: Pseudohercostomus echinatus Stackelberg by original designation.

Brooks, 2005: 857 (synonymy; discussion on systematic position).

Genus diagnosis. Robust, Dolichopodinae-like species but antennal scape lacking dorsal bristles and with a long inner apical projection. Metepimeron very wide. Anterior third of mesoscutum uniformly covered with short bristles. Acrostichals biserial or quadriserial. Hind coxa with a long, almost apical exterior bristle. Legs with strong bristles. Mid and hind femora wide and laterally flattened, with a very strong anterior preapical bristle. Mid and hind tarsomeres 1–4 anterodorsally covered with combs of short bristles. Male with only five external abdominal segments visible. Terminalia small, encapsulated in the apical segments of the abdomen. Hypopygium not stalked. Sperm pump bilobate ( Brooks, 2005). Female terminalia with hemitergites (acanthophorites) with tergite 9+10 covered with several rows of spines (acanthae).

There are several additional characters that are particular and that seem to be typical for the genus such as the mid and hind tarsi tapering towards the tip, and the apical tarsomere of the mid and hind tarsi dorsally bearing a pair of claw-like apical bristles. The mid and hind tibiae are anterodorsally naked, lacking anterodorsal short bristling except for extreme base and apical fifth; simultaneously the rows of anterodorsal and posterodorsal bristles become very strong towards apex of the tibia.

The terminology of the appendages of the male terminalia is not clear though we follow Brooks (2005). The basoventral epandrial bristle close to the base of the hypandrium is very long. The apicoventral epandrial bristle is very short, inserted on a short papilla, probably representing the reduced apicoventral epandrial lobe. The ventral surstylus bears a variable number of ventral bristles. The tip of the dorsal surstylus bears a subapical short black spine inserted at the inside.