Morphology of the alimentary tract in relation to diet among gobioid fishes

Abstract

The morphology and general course of the alimentary canal, the relative length, number and morphology of the gill rakers and the pattern of the buccal and pharyngeal dentition in 20 spp. of gobioids belonging to 3 families are studied [Awaous stamineus (Val.), Pseudogobius javanicus (Blkr.) and Oxyurichthys tentacularis (Cuv. and Val.), O. microplepis (Blkr.), Stenogobius gymnopomus (Blkr.), Oligolepis acutipennis (Cuv. and Val.), Acentrogobius caninus (Cuv. and Val), Bathygobius fuscus (Rupp.), A. reichei (Blkr.), A. chlorostigmatoides (Blkr.), A. cyanomos (Blkr.), Pseudogobius oligactis (Blkr.), Glossogobius giuris (Ham.), G. biocellatus (Cuv. and Val.), G. minutus (sp. nov.) Ctenogobius veliensis (sp. nov.), Eleotris fusca (Bl. Schn.), Butis butis (Ham.), Odontamblyopus rubicundus (Ham.), Taenioides cirratus (Blyth)]. The food of the species studied is analyzed from gut contents. Depending on the predominance of different food items in the gut the fishes can be categorized into herbivores feeding on algae, omnivores on algae, crustaceans or fish, any of which may be dominant and detritivores on soft benthic ooze. The morphology of the alimentary canal, the R.L.G. [relative length], the morphology of the gill rakers and the pattern of buccal and pharyngeal dentition are related to the food of the fishes.