Intra-specific morphological variation and genetic variation of two colour morphs
of (that are identified as red and normal colour varieties) indigenous, long-snouted
barb Puntius dorsalis (Family Cyprinidae) from two freshwater bodies in southern
Sri Lanka (Dediyagala stream and Godapitiya wewa) was studied using
morphological and allozyme electrophoresis analysis. A conspicuous red colour in
fins at all life stages from juveniles to adults could be seen in red colour morph
while yellowish colour fins are seen at all life stages of normal colour morph.
There was no black blotch in caudal peduncle and dorsal fin of red colour morph
while they could be seen in normal colour morph.
Seven morphometric characteristics (CPL, HL, PROL, HD, MBD, PAL and
HPDD) describing the shape of the fish were significantly different between two
colour morphs of P. dorsalis. Significantly shorter PROL (5.84 ± 1.05 % SL in
normal colour morph vs. 8.68 ± 1.12 % SL in red colour morph) of normal colour
morph than red colour morph is found. PROL has the greatest power to
discriminate the two colour morphs. The results of PCA showed a good separation
between two colour morphs with a little overlap. Derived classification functions
from morphometric characters could correctly classify an average of 85.7%
individuals into two colour morphs. Considering meristic characters, there was a
significant difference in number of rows of transverse scales (Tr.) between two
colour morphs. In red colour morph, it was Tr. 3'A - 2Vi and in normal colour
morph, it was 4% - 2 /2 respectively above and below the lateral line. The scales of
red colour morph were large in size than normal colour morph. The shape of the
scales in the normal morph was discernibly of rhomboid. The results indicate an
important degree of spatial separation in morphology in P. dorsalis between the
two studied colour morphs.
Intra-specific morphological variation and genetic variation of two colour morphs
of (that are identified as red and normal colour varieties) indigenous, long-snouted
barb Puntius dorsalis (Family Cyprinidae) from two freshwater bodies in southern
Sri Lanka (Dediyagala stream and Godapitiya wewa) was studied using
morphological and allozyme electrophoresis analysis. A conspicuous red colour in
fins at all life stages from juveniles to adults could be seen in red colour morph
while yellowish colour fins are seen at all life stages of normal colour morph.
There was no black blotch in caudal peduncle and dorsal fin of red colour morph
while they could be seen in normal colour morph.
Seven morphometric characteristics (CPL, HL, PROL, HD, MBD, PAL and
HPDD) describing the shape of the fish were significantly different between two
colour morphs of P. dorsalis. Significantly shorter PROL (5.84 ± 1.05 % SL in
normal colour morph vs. 8.68 ± 1.12 % SL in red colour morph) of normal colour
morph than red colour morph is found. PROL has the greatest power to
discriminate the two colour morphs. The results of PCA showed a good separation
between two colour morphs with a little overlap. Derived classification functions
from morphometric characters could correctly classify an average of 85.7%
individuals into two colour morphs. Considering meristic characters, there was a
significant difference in number of rows of transverse scales (Tr.) between two
colour morphs. In red colour morph, it was Tr. 3'A - 2Vi and in normal colour
morph, it was 4% - 2 /2 respectively above and below the lateral line. The scales of
red colour morph were large in size than normal colour morph. The shape of the
scales in the normal morph was discernibly of rhomboid. The results indicate an
important degree of spatial separation in morphology in P. dorsalis between the
two studied colour morphs.
