Osteology and myology of the cephalic region and pectoral girdle of Plotosus lineatus, with comments on Plotosidae (Teleostei : Siluriformes) autapomorphies

From comparisons of the cephalic and pectoral girdle structures of Plotosus lineatus with those of other plotosid as well as non-plotosid siluriforms, plotosid catfishes can be defined by at least six autapomorphies. These ar e: (1) the absence of the ventral division of the muscle arrector dorsalis; (2) the double articulation between the neurocranium and the anterior part of the suspensorium (3) the greatly enlarged utricular otolith, which prof oundly inflates the ventral surfaces of both the prootic and the pterotic; (4) the attachment of the muscle extensor tentaculi on the neurocranium lie s further anteriorly than its insertion on the autopalatine (5) the coronoi d process of the inaudible is linked to the maxillary by means of two thick , long ligaments; (6) the enlarged base of the maxillary barbel. (C) 2001 T he Fisheries Society of the British Isles.