The morphology of the catfish horizontal cells is comparable to that in other fish retinas. The external horizontal cells contact cone receptors and are stellate in shape; the intermediate horizontal cells are even more so and contact rod receptors.
What is the body shape of clarias Gariepinus?
Diagnosis: body depth 6-8 times in standard length, head 3-3,5 times (Ref. 34290). Head somewhat between rectangular and pointed in dorsal outline; snout broadly rounded; eyes supero-lateral and relatively small (Ref. 248).
What are the adaptive features of clarias Gariepinus?
They are very adaptive to extreme environmental conditions and can live in pH range of 6.5-8.0. They are able to live in very turbid waters and can tolerate temperatures of 8-35 degrees Celsius. Their optimal temperature for growth is 28-30 degrees Celsius (Teugels 1986).
How do you identify clarias Gariepinus?
These fish have slender bodies, flat bony heads, notably flatter than in the genus Silurus, and broad, terminal mouths with four pairs of barbels. They also have large accessory breathing organs composed of modified gill arches. Also, only the pectoral fins have spines.
Are catfish invasive?
Blue catfish are considered an invasive species in the Chesapeake Bay. They were introduced to several rivers on Virginia’s Western Shore decades ago. They swam out into the Bay and back into other rivers. And people moved them from one river to another, too.
What are the characteristics of catfish?
Cat Fish Characteristics Catfish have no scales. All catfish, except members of Electric Catfish family, possess a strong, hollow, bony leading ray on their dorsal and pectoral fins, through which a stinging protein can be delivered if the fish is irritated.
How can we recognized the male C Gariepinus based on its body?
gariepinus can be easily recognized as the male has a distinct sexual papilla, located just behind the anus. This sexual papilla is absent in females (Figure 4).
Does clarias Gariepinus have adipose fin?
The species has 61–75 dorsal rays and 45–60 anal fin rays. Dorsal fin extends from behind head nearly to base of caudal fin. Anal fin extends from base of anus to base of caudal fin. No adipose fin.
What’s the best tasting catfish?
flatheads
Some anglers believe flatheads’ diet is responsible for their superior table quality. And a properly cleaned flathead (be sure to remove the yellow fat in the meat) is unquestionably the best tasting of all catfish.
What do Clarias catfish eat?
Wild Clarias like insects and fish, but don’t care whether food is dead or alive. It’s almost as though they lack the sense to tell the difference. Carrion or fresh, they’ll take the lot. It seems the younger cats prefer insect food, while adults have a thing for smaller fish, fry and eggs.
How many gill rakers does a Clarias gariepinus have?
Contrary to other Clarias species, Clarias gariepinus has a high number of gill rakers varying from 24-110 (Ref. 248, 34290, 81644, 101841 ), the number increasing with size of the fish; gill rakers long, slender and closely set (Ref. 248, 34290 ).
Where did the African catfish come from?
Several strains of the African catfish have been introduced to Indonesia for aquaculture purposes, initiated by Dumbo strain from Taiwan in 1985, followed by Paiton strain from Thailand in 1998, then Egypt strain from Egypt in 2007, Masamo strain from Thailand in 2010 and later Kenya strain from Kenya in 2011.
What is the etymology of Clarias?
Etymology: Clarias: Greek, chlaros = lively, in reference to the ability of the fish to live for a long time out of water; gariepinus: Named after its type locality, the Gariep river, the Hottentot name for the Orange river, South Africa.
How long does a sharptooth catfish electric discharge last?
During intra-specific aggressive interactions, this species was noted to generate electric organ discharges that were monophasic, head-positive and lasting from 5-260 ms (Ref. 10479 ). Known as sharptooth catfish in aquaculture, a highly recommended food fish in Africa (Ref. 52863 ).
