PARMENTIER, E.*; LAGARDERE, F.; DIOGO, R.; VANDEWALLE, P.: Study of the otoliths and otic area in Carapidae fishes : Eco-morphological implications ?

Carapidae-family species are characterised by so-called otophysical structures (sonic muscles, broad first apophyses covering the anterior part of the swimbladder, etc.) The family includes pelagic (e.g..Pyramodon sp.) and benthic (e.g. Echiodon sp.) species and ones that are either commensal (e.g..Carapus sp.) or parasites of (e.g. Encheliophis sp.) invertebrates (sea cucumbers, etc). The aim of the work is to seek possible relationships between the structures of the inner ear on the one hand and otophysical structures and lifestyles within the Carapidae family. In the eight species studied, the otic cavity is wide, the saccular otosac and its sagitta are particularly developed. The sacculi touch each other on the median line. A comparison of the inner ear structures reveals notably that the species with the most developed sagitta and sacculus are those with the largest parapophyses. These structures, both auditory and otophysical, are most developed in species that are not completely free-swimming, i.e., with a commensal or especially a parasitic lifestyle.