Eleven new species of Sericostomatoidea from Madagascar (Trichoptera: Helicopsychidae, Petrothrincidae, Sericostomatidae) Author Johanson, Kjell Arne Author Oláh, János text Zootaxa 2006 1205 1 30 journal article 50790 10.5281/zenodo.172376 54e48000-e28d-42b8-993e-d39b4923683f 1175­5326 172376 Helicopsyche ( Petrotrichia ) Ulmer, 1910 Type species: Helicopsyche palpalis (Ulmer, 1910) : 44. The genus Petrotrichia was established for a species described from Mahé Island in the Seychelles , and originally classified within the Hydroptilidae . The species was transferred to Helicopsyche by Marlier & Malicky (1979) . Johanson (1998) argued for a phylogenetically close relationship between the African species of the genus ( Seychelles , Madagascar and East Africa) and referred them to the subgenus Petrotrichia . Species of this subgenus are recognized by maxillary palps divided into a short basal and long distal segment, the basal segment bearing strong median setae; interantennal setal warts flat or absent; head tentorium without processes; forewing fork 3 and Cu1b absent, forewing crossvein R3­R4 directed posteriad, hind wing fork 1 longer than its stalk, crossvein M­Cu absent, Cu1 undivided; and abdominal reticulation reduced. The Madagascan species are recognized by having a longitudinal fold in the forewing, with sensillae located between veins M and Cu.