Thryssa mystax is silver, darker dorsally. There is a distinctive dark blotch behind upper part of gill opening, which can easily identify the species from other "Thryssa" species. Caudal fin is yellowish. It feeds on planktons, fish larva, and small crustaceans like shrimp larva. Thryssa mystax The moustached thryssa ("Thryssa mystax"), also known as Gangetic anchovy, is a species of oceanodromous ray-finned fish in the family Engraulidae. It is found in the tropical western Indo-Pacific region from India, Sri Lanka to Myanmar and south to Java, and Indonesia. It is a small schooling fish found in depth of 0-50m. Maximum length do
Fish fin preferred females with a larger pelvic fin and that pelvic fins grew in a more disproportionate way than other fins on female fish." There are two prevailing hypotheses that have been historically debated as models for the evolution of paired fins in fish: the gill arch theory and the lateral fin-fold theory. The former, commonly referred to as the “Gegenbaur hypothesis,” was posited in 1870 and proposes that the “paired fins are derived from gill structures”. This fell out of popularity in favor of the lateral fin-fold theory, first suggested in 1877, which proposes that paired fins budded from longitudinal,