Clarias insolitus, a new species of clariid catfish (Teleostei: Siluriformes) from southern Borneo

Heok Hee Ng


resenting a short abstract from the latest paper (Sept.2003) from Heok Hee Ng.


A new species of catfish in the genus Clarias is described from the Barito River drainage in southern Borneo. Clarias insolitus can be clearly distinguished from all other Southeast Asian Clarias species in having a long and thin anterior fontanel and hypertrophied sensory canal pores on the head and body that are easily visible to the naked eye. Additional diagnostic characters not unique to this species are a uniform violet-gray color without any white spots on body and prominent serrations on the anterior edge of the pectoral spine.

Key words: Clariidae, Kalimantan Tengah, Barito River

The genus Clarias Scopoli, 1777 is a group of air-breathing catfishes found in inland waters throughout much of the Old World. They are easily identified by an anguilliform body, long-based dorsal and anal-fins, eye with free orbital margin and located dorsolaterally, large and well-developed neurocranium and the presence of an accessory breathing organ comprised of modified gill arches. Although the bulk of Clarias diversity is found
in Africa (Teugels, 1986), 18 nominal species, 12 of which are currently considered valid (Ng, 1999; 2001), are known from Southeast Asia. As recent studies have shown, the diversity of Southeast Asian Clarias is higher than previously thought and undescribed taxa are still being described. During an examination of material collected during an ichthyological survey of the upper Barito River drainage in southern Borneo, a highly distinctive species of Clarias with characters not previously seen in other Asian congeners was discovered. This material is described as Clarias insolitus, new species.
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