Nakamura, M;
Keys to the Freshwater Fishes of Japan Fully Illustrated
in Colors(2) KENPEI
(1) Ben
Lee (1)
ScotCat
Sources:
Other
Sources:
Relevant
Information:
One of three species of Silurus
that are in Japan and is also the largest. The rock
catfish, S.
lithophilus, the Biwi
catfish, S. biwaensis and the far eastern
catfish S.
asotus.Reproduction: Based on observations,
a female first searches for a spawning site, with
a male following behind. Immediately the female stops,
the male first places his head under that of the female
and then, by bending his body towards her anal fin,
positions himself such that his tail is towards the
end of the female's snout. From this position, the
male then begins to wrap his tail around the head
of the female, gradually winding his body tighter
and moving along the body of the female until positioned
at the center of her body. The male then winds his
body tightly around the dorsal side of the female's
abdomen for 20-30 seconds. The female then shakes
her head from side to side several times, and orientates
her body downward. This behavior causes the male to
become separated from the female. Immediately after
separation, the female releases a large number of
eggs, and circles around with the male following on
the inside. Although gamete release by the male was
not actually observed, it seems likely that the eggs
are fertilised during circling. After circling, the
pair turns round twice violently, causing the eggs
to become widely scattered. The pair then swim away
with the female in the lead.
Common
Name:
Eurasian catfish, Biwi catfish
Synonyms:
Parasilurus biwaensis
Family:
Siluridae
Distribution:
Asia:Endemic to Lake Biwa, Japan. Type
locality: Offshore of Onoé, Lake Biwa-ko,
Japan.
Size:
115.0cm. (3ft 10ins)
Temp:
10-20°C (47-67°F)
p.H.
6.0-8.0.
Reference:
Ferraris, C.J. Jr.,
2007. Checklist of catfishes, recent and fossil (Osteichthyes:
Siluriformes), and catalogue of siluriform primary
types. Zootaxa 1418:1-628. Froese, R. and D. Pauly. Editors.
2021. FishBase. World Wide Web electronic publication.
www.fishbase.org, ( 08/2021 ). Kobayakawa, M.,
1989. Systematic revision of the catfish genus Silurus,
with description of a new species from Thailand and
Burma. Jap. J. Ichthyol. 36(2):155-186. Nakamura, M;
Keys to the Freshwater Fishes of Japan Fully Illustrated
in Colors. Hokuryukan, 1963.
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