Spaniotoma angusta

Ferrington Jr, Leonard C. & Saether, Ole A., 2011, A revision of the genera Pseudosmittia Edwards, 1932, Allocladius Kieffer, 1913, and Hydrosmittia gen. n. (Diptera: Chironomidae, Orthocladiinae) 2849, Zootaxa 2849 (1), pp. 1-314 : 254

angusta group

Transverse sternapodeme without oral projections; superior and median volsellae present and digitiform or lobe-like, occasionally fused; median volsella occasionally double or apically bifid, perhaps absent or fused with inferior volsella in P. lamasi ; inner surface of gonostylus or of secondary lobe covered by long and dense microtrichia or numerous setae except in P. gibbistyla and P. umbonata ; crista dorsalis evident except in the angusta subgroup and P. adunca . Female antenna with apical seta except in P. forcipata , tergite IX divided, seminal capsules with fine microtrichia except in P. pedata , spermathecal ducts with common openings and without bulbs before opening. Pupa without anal macrosetae and median seta on anal lobe. Antennal blade of larva 2–3.5 times as long as width of basal segment, mandible without dorsal teeth, posterior parapods with 0–6 slender claws, anal tubules without constrictions.

The group can be divided into five subgroups, the paraphyletic or occasionally monophyletic angusta subgroup consisting of P. angusta and P. aculeathrix , the danconai subgroup, the trilobata subgroup, the uncata subgroup, and the forcipata subgroup. P. lamasi , however, cannot easily be placed in any of these groups and forms a monotypic subgroup.