primitive catfish family from the rivers of
Chile and Argentina so would therefore be considered
cool water catfishes.
only maxillary barbels present; dorsal fin with
spine and 6 or 7 rays; anal fin with 9-12 principal
rays; adipose fin present; pectoral fin with
spine. Very rarely seen in the trade so there
is not much
information on keeping the 6 known species in
the Diplomystes genera.
Arratia (1987) erected the genus Olivaichthys
for the Argentinian specimens but some authors
still treat Olivaichthys
as a synonym of Diplomystes.