Rheocricotopus (Psilocricotopus) robacki (Beck & Beck, 1964)

Liu, Wenbin, Lin, Xiaolong & Wang, Xinhua, 2014, A review of Rheocricotopus (Psilocricotopus) chalybeatus species group from China, with the description of three new species (Diptera, Chironomidae), ZooKeys 388, pp. 17-34 : 24

Rheocricotopus (Psilocricotopus) robacki (Beck & Beck, 1964)

Tricocladius robacki Beck & Beck, 1964: 204.

Rheocricotopus kenorensis Sæther, 1969: 88.

Rheocricotopus (Psilocricotopus) robacki Sæther, 1985: 79, Ashe and O’Connor 2012: 567.

Specimens examined.

1♂, Shaanxi Province, Xi’an City, Zhouzhi County, Banfangzi, 33°81'84"N, 107°99'64"E, 10.viii.1994, light trap, Ji BC; 8♂♂, Jiangxi Province, Yichun City, Yifeng County, 28°39'69"N, 114°67'55"E, sweeping, Yan CC; 1♂, Fujian Province, Longyan City, Shanghang County, 25°05'21"N, 116°41'52"E, 6.v.1993, sweeping, Wang XH; 2♂♂, Xinjiang Uygur Autonomous Region, Boertala Mongol Autonomous Prefecture, Sailimu lake, 44°62'32"N, 81°20'48"E,30.vii.2002, sweeping, Tang HQ; 7♂♂, Guizhou Province, Zunhua City, Daozhen County, Dasha River, 28°86'58"N, 107°60'73"E, 25.v.2004, light trap, Tang HQ; 2♂♂, Guizhou Province, Zunhua City, Daozhen County, Dasha River, 28°86'58"N, 107°60'73"E, 24.viii.2004, sweeping, Yu X; 3♂♂, Yunnan Province, Dali Bai Autonomous Prefecture, Eryuan County, Niujie Town, 26°25'55"N, 99°98'90"E, light trap, Wang BX; 1♂, Tibet, Xigaze, Nielamu County, 27°98'73"N, 85°98'32"E, 15.8.1987, light trap, Deng CY; 1♂, Tibet, Xigaze, Nielamu County, 27°98'73"N, 85°98'32"E, 21.9.1987, light trap, Deng CY.

Diagnosis.

The species is characterized by having a relatively high AR (1.14-1.24), very weak and short acrostichals, 8-14 dorsocentrals, reduced number of bristles on squama, anal tergite extending beyond tip of anal point, superior volsella triangular, crista dorsalis triangular, apex pointed.

Remarks.

Chinese specimens mainly agree with the description of Sæther (1969, 1985). It is recorded in Palearctic Region for the first time. Chinese specimens have lower body length (2.55-3.13 mm) and lower AR 1.07 than species from Nearctic Region (total length 3.10-3.30 mm, AR 1.18).

Distribution.

China (Fujian, Guizhou, Jiangxi, Shaanxi and Yunnan Provinces, Xinjiang Uygur Autonomous Region, Tibet), Canada, U.S.A.