Reproductive biology of Leiognathus splendens was studied by using the samples collected from the catches of trawl fisheries in Myeik coastal waters during January to December 2014.Spawning takes place throughout the ...Reproductive biology of Leiognathus splendens was studied by using the samples collected from the catches of trawl fisheries in Myeik coastal waters during January to December 2014.Spawning takes place throughout the year,with a peak during April-May and September-December.The observed length at first maturity was 9.0 cm total length in males and 8.4 cm in females.The mean gonadosomatic index was more prominently in females(2.5)than males(1.5).Sex ratio(1 male:1.1 females)also indicates the general dominant of females over males Fecundity varied from 6120 to 58412 eggs.Relationship of fecundity to fish length,fish weight and ovary weight showed that fecundity is more related to the gonad weight(r=0.9)than length(r=0.8)and weight of fish(r=0.7).展开更多
Ponyfishes of the family Leiognathidae frequently show overlapping distribution pattems in the Indo-Pacific and South China Sea. The mouth morphology of three species of ponyfishes which feed at different lerels in th...Ponyfishes of the family Leiognathidae frequently show overlapping distribution pattems in the Indo-Pacific and South China Sea. The mouth morphology of three species of ponyfishes which feed at different lerels in the water column were compared. The species could be distinguished primarily by the mouth meropology. Gazza minuta (Bloch)feeds mainly on bethos, has the least protruding jaws; Secutor ruconius (Hamilton-Buchanan) feeds mainly on plankton, has the most protruding jaws, Leiognathus rivuatus (Temmink et Schlegel) has an intermediate deggree of jaw protrusion. This study showed that closely related species with overlapping distributions frequently exhibit morphologlcal, phpsiological or ecological differences related to the search for food, the intake of food or locomotion mode.展开更多
文摘Reproductive biology of Leiognathus splendens was studied by using the samples collected from the catches of trawl fisheries in Myeik coastal waters during January to December 2014.Spawning takes place throughout the year,with a peak during April-May and September-December.The observed length at first maturity was 9.0 cm total length in males and 8.4 cm in females.The mean gonadosomatic index was more prominently in females(2.5)than males(1.5).Sex ratio(1 male:1.1 females)also indicates the general dominant of females over males Fecundity varied from 6120 to 58412 eggs.Relationship of fecundity to fish length,fish weight and ovary weight showed that fecundity is more related to the gonad weight(r=0.9)than length(r=0.8)and weight of fish(r=0.7).
文摘Ponyfishes of the family Leiognathidae frequently show overlapping distribution pattems in the Indo-Pacific and South China Sea. The mouth morphology of three species of ponyfishes which feed at different lerels in the water column were compared. The species could be distinguished primarily by the mouth meropology. Gazza minuta (Bloch)feeds mainly on bethos, has the least protruding jaws; Secutor ruconius (Hamilton-Buchanan) feeds mainly on plankton, has the most protruding jaws, Leiognathus rivuatus (Temmink et Schlegel) has an intermediate deggree of jaw protrusion. This study showed that closely related species with overlapping distributions frequently exhibit morphologlcal, phpsiological or ecological differences related to the search for food, the intake of food or locomotion mode.
