Original scientific paper
TAXONOMIC AND OTOLITH SHAPE PARAMETERS OF NINE SYMPATRIC CATFISHES COMMERCIALLY HARVESTED IN PAKISTAN
2023, 81 (1) p. 0-0
Noureen Farooq, Sher Khan Panhwar
Abstract
Accurate reorganization of harvested species is essential for appropriate fisheries monitoring but is often unnoticed. In this study, an attempt was made to provide an accurate species description based on fish taxonomy and otolith shape parameters of nine sea catfishes living in Pakistan. The lapillus, the largest otolith of catfishes, includes the position of the umbo, the structure of the anterior mesial projection (amp), the incisura linea basalis (ilb) and sulcus lapilli marks (slm) in nine ariid catfishes. Discriminant function analysis was performed using twenty-two morphometric parameters of nine species, and showed significant variations between the length of the maxillary barbel, adipose length and preorbital length, which were highlighted as basic discriminating characters. Species without barbells, such as Batrachocephalus mino and Osteogeneiosus militaris, were found to be distant. The taxonomic characters of the genera Netuma and Plicofollis overlapped due to a short adipose fin length. Nevertheless, species Arius arius, Sciades sona and Nemapterxy caelatus differed in a moderate adipose fin length. The preorbital length of Netuma bilineata has a short and rounded snout, while N. thalassina has a long and pointed snout, which is a distinguishing characteristic of both species. The coincident use of fish taxonomy and otolith shape parameters is an effective tool for catfish identification which helps in appropriate fisheries sampling programs and management in Pakistan whenever implemented.
Keywords
Fish taxonomy, lapillus otoliths, species segregation, catfishes, Ariidae, multivariate approach