Parachanna insignis
{pronunciation} in-sig-nis
First description:
Sauvage, H.E. 1884.
Ophiocephalus insignis.
Bulletin Du Societe Zoologique (France). p.195; pl.V; fig.3.
Diagnostic:
Compared with P.obscura, P.insignis has a sharper contrast in the pattern,
even in the fright stage. It also has much longer nostrils in comparison with P.obscura.
Meristic:
D: 40-44 A: 27-31 C: rounded V: present Ratio: 30.6-35.3 %
Ll:
73-90
Description:
At 250 mm the colouration of this species can vary tremendously according to
it's mood or enviroment. Dorsal and anal fins are clear with numerous spots
and blotches which become progressively larger nearer the body. The caudal
is black, becoming lighter when it joins the peduncle. A large, dark spot
can be observed in the mid fin. Ventral and pectoral fins are spotted.
The body is black and white in varying shades, the upper portion having 6-7
patches beneath the dorsal fin, with a further 7 larger patches centrally
from the opercle to the caudal. The belly is speckled.
On the head, a black wedge- shaped pattern begins at the snout and runs
through the eye to the opercle. The underside of the mottled chin is black
and white. Viewed from above, the head is flattish which, in turn, places
the eye high up on the face.
Size:
Total length to 532 mm
Sub-species and colour variants:
An in-depth study of the two closely related species,
P.insignis and P.obscura, was conducted by
Teugels & Daget (1984).
Close scrutiny of the scale counts of 68 preserved specimens revealed
differences, that are recorded in the table below, based on the following
characters :-
a) Upper transverse scale count
A count of scales from the first ray of the dorsal fin, downwards to the
lateral line, although the scale perforated by the lateral line is not included.
b) Lower transverse scale count
The imaginary line is followed downwards, till it reaches the middle of the
pelvic fin base.
c) Lateral line count
|
P.insignis |
P.obscura |
| Upper Transverse |
8-9 |
6-7 |
| Lower Transverse |
18-21 |
4-16 |
| Lateral line |
76-86 |
64-78 |
Finally, the preserved specimens of P.insignis also generally showed a lighter colour.
Synonyms:
Ophiocephalus insignis, Channa insignis, Parophiocephalus insignis.
Geographical location:
Boulenger (1916)
reports that this fish ranges from Cameroons to the Congo.
The Ogowe basin and Zaire basin were mentioned by
Teugels & Daget (1985).