DISTINCTIVE ANATOMICAL FEATURES OF THE BRANCHIAL BASKET IN 4 CARAPIDAE SPECIES (OPHIDIIFORMI, PARACANTHOPTERYGII)

The present study focuses on the branchial basket in four Carapidae sp ecies: Carapus acus, Encheliophis boraborensis, Encheliophis homei and Encheliophis gracilis. The aim is to highlight the skeletal and muscu lar features of the branchial basket, especially those that are believ ed to be related to their way of life and/or to be linked to the prese nce of primary sound-producing muscles. The space occupied by the prim ary sound-producing muscles between the neurocranium and the branchial basket gives rise to distinctive skeletal and muscular features. They prevent the Ist pharyngobranchials Stem becoming attached to the neur ocranium in the normal way. These do not seem to play any role in the suspension of the the upper pharyngeal jaws, as it is usually the case in teleosteans. The Ist epibranchials are separated from the 2nd phar yngobranchials. Ossified interarcual elements jointed to the 2nd phary ngobranchials and Ist epibranchials are found in the position usually occupied by the latter The presence of primary sound-producing muscles gives rise to the need for the reorganisation of the musculature whic h is seen in particular with regards to the levatores branchiales. The se al-e not found on the neurocranium but on the hyomandibular The gen eral skeletal and muscular data and the observations of the stomach co ntents suggest that the action of the branchial basket is restricted t o carrying food in Carapus acus, Encheliophis boraborensis and Encheli ophis homei, whereas it could also play a sole in the work of cutting up soft food in Encheliophis gracilis.