K. Watanabe et al., MORPHOLOGICAL-CHARACTERISTICS IN THE 2 FO RMS OF FLATFISH, GENUS PLEURONICHTHYS, IN KIISUIDO CHANNEL WATERS OFF THE PACIFIC COAST OF CENTRAL JAPAN, Nippon Suisan Gakkaishi, 62(1), 1996, pp. 23-27
Morphological differences between the two forms of Pleuronicthys were
investigated. These two forms, Honmeita and Bakemeita, were clearly di
stinguished by comparing the arrangement of scales on the right side o
f the body. Scales were arranged regularly in a line on the central pa
rt of the right body side in the Honmeita, but were arranged irregular
ly in the Bakemeita except near the lateral line. The mean numbers of
precaudal vertebrae, dorsal fin rays, anal fin rays, caudal fin rays a
nd upper gill rakers of nine meristic characters examined were differe
nt at a statistically significant level between the two forms. The rel
ative growth of various body parts to the body length, such as body he
ight, diameter of eye, depth of caudal peduncle, length of caudal pedu
ncle, height of longest dorsal say, length of longest pectral ray and
length of longest anal ray were significantly different between the tw
o forms. Branching of the lateral line under the base of the dorsal fi
n was observed in 9.2 percent of Honmeita, and 84.4 percent of Bakemei
ta. The complete differences in the arrangement of scales and the stat
istical differences in these morphological characters provide evidence
of the distinctiveness of the two forms as the species.