Petrothrincus Barnard, 1934 : 323

Johanson, Kjell Arne & Oláh, János, 2006, Eleven new species of Sericostomatoidea from Madagascar (Trichoptera: Helicopsychidae, Petrothrincidae, Sericostomatidae), Zootaxa 1205, pp. 1-30 : 10

Petrothrincus Barnard, 1934: 323 , 325.

Gyrocarisa Weaver, 1997: 467 –468. New synonym

Type species: Petrothrincus circularis Barnard, 1934: 325 –327.

The Madagascan genus Gyrocarisa Weaver was separated from the South African genus Petrothrincus on the basis of dorsal posterolateral setal warts of the head reniform in both male and female, and forewing with a short discal cell in both male and female. Evidence from the new species from Madagascar, suggests that the shape and pattern of the setal warts on the head and thorax are not very stable. Also, the length of discal cell varies between 1x and 3x its width in the species described here. Moreover, in number of segments, and ratios of length and shape of the male maxillary palp vary to a very great extent. The basic patterns of the genitalia structures as well as forewing venation are very similar and stable between the species. Based on these new findings, division of the species referred to Petrothrincidae into different genera is indefensible. In this paper, Gyrocarisa is therefore synonymized with Petrothrincus .