Taxonomy, Distribution and Evolution of Trisopterine Gadidae by Means of Otoliths and Other Characteristics

Author:
Open Access
Publisher website
Google Scholar
Abstract
In a greater study of the recent fossil Gadidae, the object of this paper is to better define the trisopterine species and their relationships. The taxonomy of the four recent species usually included in the genus Trisopterus is further elaborated by means of published and new data on their otoliths, by published data on general external features and meristics of the fishes, and their genetics. Fossil otoliths, from the beginning of the Oligocene up to the present, reveal much of their evolution and throw more light on their relationships. Several succeeding and partly overlapping lineages representing different genera are recognized during this time interval. The genus Neocolliolus Gaemers, 1976, for Trisopterus esmarkii (Nilsson, 1855), is more firmly based. A new genus, Allotrisopterus, is introduced for Trisopterus minutus (Linnaeus, 1758). The similarity with Trisopterus capelanus (Lacepède, 1800) is an example of convergent evolution. The tribe Trisopterini Endo (2002) should only contain Trisopterus, Allotrisopterus and Neocolliolus as recent genera. Correct identification of otoliths from fisheries research and from sea bottom samples extends the knowledge of the present day geographical distribution of T. capelanus and T. luscus (Linnaeus, 1758). T. capelanus is also living along the Atlantic coast of Portugal and at least up to and including the Ría de Arosa, Galicia, Spain. There it can easily be mistaken for A. minutus that is also living there. Otoliths of T. luscus have been identified from the Evvoïkós Channel between Euboia and the mainland of Greece, thus it must live also in the Aegean Sea. Otoliths prove to be a powerful tool in taxonomy, biogeography and evolution of teleosts.

This publication has 35 references indexed in Scilit: