Gomphidictinus perakensis

Fraser erected Gomphidictinus as a separate genus from Gomphidia based on the ventral spine on the penis. Until I found the as yet undescribed new species sharing this characteristic, Gomphidictinus had only one member species, Gomphidictinus perakensis. It has been questioned whether the spine on the penis warrants separation from Gomphidia. Apart from this character, the species looks very much like other Gomphidia species.

According to the IUCN website, this species occurs widely in Malaysia, Thailand and Laos and a specimen of unknown exact provenance, but from Vietnam, is kept in the collections of the Natural History Museum in London. Karube (2014) mentions two records from 1996 and 2003, both from Lam Dong in southern Vietnam. According to him, these are the first records for Vietnam. These two statements appear contradictory. Karube assumes that G. perakensis only occurs in southern Vietnam. However, I saw one male on a stream in northern Bac Kan Province on June 22, 3 males on a different stream also in northern Bac Kan Province on June 25, and on July 7 2 males at a stream approximately 25km from these locations in southern Cao Bang Province. Clearly the species occurs right up to the Chinese border in Vietnam.

Male Gomphidictinus perakensis, June 22 Bac Kan Province

Another male in hand on June 25, also Bac Kan Province

Another male, July 7 in Cao Bang Province

Frontal view of the face 

Dorsal view of thorax

Distinctive appendages in dorsal view

And in lateral view