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.
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.
Leviton, A.E., Gibbs, R.H.Jr., Heal, E. & Dawson,
C.E. (1985) Standards in herpetology and ichthyology:
Part I. Standard symbolic codes for institutional
resource collections in herpetology and ichthyology.
Copeia, 1985, 802–832.
Ng, H.H. (1999) Two new species of Clarias from Borneo
(Teleostei: Clariidae). The Raffles Bulletin Zoology,
Ng, H.H. (2001) Clarias microstomus, a new species
of clariid catfish from eastern Borneo (Teleostei
Siluriformes). Zoological Studies,
Roberts, T.R. (1994) Systematic revision of Asian
bagrid catfishes of the genus Mystus sensu stricto,
with a new species from Thailand
and Cambodia. Ichthyological Exploration of Freshwaters,
Tan, H.H. & Ng, H.H. (2000) The catfishes (Teleostei:
Siluriformes) of central Sumatra. Journal of Natural
History, 34, 267–303.
Teugels, G.G. (1986) A systematic revision of the
African species of the genus Clarias (Pisces; Clariidae).
Annales Musée Royal de l’Afrique
Centrale. Sciences Zoologiques, 247, 1–199.
Teugels, G.G., Diego, R.C., Pouyaud, L. & Legendre,
M. (1999) Redescription of Clarias macrocephalus
(Siluriformes: Clariidae) from South-east Asia. Cybium,