Rheocricotopus (Psilocricotopus) tobatervicesimus Kikuchi & Sasa

Fu, Yue, Huang, Jingli, Liu, Wenbin, Fang, Xiangliang & Wang, Xinhua, 2016, Redescription of 13 holotypes of Rheocricotopus Brundin, 1956 (Diptera: Chironomidae) from the Sino – Indian Region, Zootaxa 4114 (3), pp. 261-276 : 265-266

Rheocricotopus (Psilocricotopus) tobatervicesimus Kikuchi & Sasa

( Figs 4 A–B )

Rheocricotopus (Psilocricotopus) tobatervicesimus Kikuchi & Sasa, 1990: 326 ; Ashe & O’Connor 2012: 567.

Material examined. Holotype, male, At the side of Lake Toba, Sumatra, Indonesia, 1. I. 1988, Kikuchi and Sasa (No. 200: 22).

Diagnostic characters. The species can be separated from other East Asian members of the genus by superior volsella reduced, inferior volsella developed and rounded margins, with many microtrichia, gonostylus with a triangularly rounded crista dorsalis.

Additional description and corrections. Based on the analysis of holotype material, the examined characters were consistent with the original description, but some additional characters should be added: Clypeus with 9 setae.

Tentorium 128 µm long, 30 µm wide. Dorsocentrals 8. Wing of holotype destoryed. Palpomeres length (in µm): 33, 48, 75, 92, 125. Palpomere 2 ellipsoid, 3 and 4 rectangular, 5 long and slender, Palpomeres 5/3: 1.7. Anal point 43 µm long, basal wide 20 µm, peak wide 2 µm. Transverse sternapodeme 70 µm long, with weak oral projections. Gonocoxite 152 µm long. Gonostylus 75 µm long, with crista dorsalis. Megaseta 10 µm long. HR 2.0, HV 2.2. The hypopygium of holotype are re-drawn as in Figs 4 A–B .

Distribution. The species occurs in Indonesia (Oriental Region).

Figures

FIGURE 4 A – B. Rhecricotopus (Psilocricotopus) tobatervicesimus Kikuchi & Sasa, Male imago. A. Hypopygium, dorsal view. B. Hypopygium, ventral view.