One of the best-known members of the Siluridae is the transparent species often referred to as the glass catfish. This is the most commonly encountered silurid in the ornamental fish trade in which it has been present at least since 1934. It has long been identified in aquarium literature as Kryptopterus bicirrhis, or more recently Kryptopterus minor. Despite being known to aquarists and scientists since 1934, the exact identity of the glass catfish has not been thoroughly investigated. Scientists resolve the identity of the glass catfish, a species of Asian freshwater fish commonly encountered as an ornamental fish and an experimental subject that has long been misidentified as either Kryptopterus bicirrhis or Kryptopterus minor. The study indicates that the glass catfish is an unnamed species distinct from either, which the scientists describe here as Kryptopterus vitreolus. Kryptopterus vitreolus is known from river drainages in peninsular and southeastern Thailand, and is distinguished from congeners in having a combination of: transparent body in life, maxillary barbels reaching beyond the base of the first anal-fin, dorsal profile with a pronounced nuchal concavity, snout length 29–35% head length (HL), eye diameter 28–34% HL, slender body (depth at anus 16–20% standard length (SL)) and caudal peduncle (depth 4–7% SL), 14–18 rakers on the first gill arch, and 48–55 anal-fin rays.

Kryptopterus bicirrhis looks very different. It is not that translucend. K. bicirrhis becomes about 15 cm long which is much more that K. vitreolus (about 7 cm). K. minor originates from the island of Borneo and has in all probabilty never been imported as an ornamental fish. K. vitreolus originates from Thailand only.

Lexicon:

Kryptopterus: ancient Greek, means "with hidden fin".
bicirrhis: Latin, means "with two filaments".
minor: Latin, means "small".
vitreolus: Latin, means "small glass".