Clarias anfractus is a species of clariid catfish from Borneo. It is known from the Segama and Kalabakan drainages in Sabah, Northeastern Borneo.
According to type specimens collected from Sabah, it can be found in slow pools of forested fast-flowing streams with mud and soil substrates containing substantial amounts of leaf debris. The fish were found living in holes in the substrate.[1] It has also supposedly been observed in Long Te Malinau Regency, North Kalimantan.[2]
Collected in 1999, the holotype for this specimen was noted to be 176.4 mm long (17.64 cm) from the edge of the skull to the caudal fin, with the 5 recorded paratypes ranging from 140.4 to 204.2 mm (14–20.4 cm). The diagnosis of this species includes the following characters:[1]
Other notable traits also include:
Preserved specimens are known to be gray, with paler undersides. Dorsal, caudal and anal fins are also of body color, with pelvic and pectoral fins being opaque white to translucent. Big white or yellow spots are also common in other Asian forest Clarias species. The specimens were kept in a 10% formalin solution.