Proceedings of the California Academy of Sciences, February 15, 1977, Vol. 41

Download or read book Proceedings of the California Academy of Sciences, February 15, 1977, Vol. 41 written by John E. McCosker and published by Forgotten Books. This book was released on 2018-02-12 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Proceedings of the California Academy of Sciences, February 15, 1977, Vol. 41: The Osteology, Classification, and Relationships of the Eel Family Ophichthidae Abstract. A classification of the genera of the apodal family Ophichthidae is proposed on the basis of internal and external morphology, with particular emphasis on osteological characters, Specimens of 89 ophichthid species from 44 genera and comparative material from ten other apodal families were prepared for osteological examination, usually by a trypsin-based staining and clearing technique, and critically compared. Forty-nine ophichthid genera are recognized and are distributed among six tribes in two subfamilies. Diagnostic characters for the recognition of genera include the shape and condition of elements of the gill arch and hyoid arch, number and placement of branchiostegal rays along the hyoid, sus pensorium elements, neurocrania, dentition, pectoral girdle elements, cephalic pore patterns, lateral line ossification, fin placement, and morphometric characters. The Ophichthidae are defined on the basis of their numerous overlapping branchiostegals, supraorbital canals united by a transverse commissure through the fused frontals, first and second epibranchial interconnections, absence of a palatine, and the separation of the pterygoid from the vomer. A monophetic origin of the family from a congrid-iike ancestor is proposed. An evolu tionary history of the Ophichthidae is suggested, in which the subfamily Myrophinae has separated into two tribes and the subfamily Ophichthinae has radiated into four tribes. The validity of the family name Ophichthidae is discussed. The family names Ophisuridae, Myridae, Mephidae, Muraenichthyidae, Echelidae, Neenchelidae, Aoteidae, Acanthen chelyidae and Sphagebranchidae are synonyms of the name Ophichthidae. A comparison is made between an ophichthid classification based primarily on osteology and the previous classification, based primarily on external morphology. The results of two computer-pro grammed classification schemes of species relationships within a single tribe are compared with a classification developed using traditional methodology. Alternate hypotheses are pro posed to explain the log-normal inverse relationship between genera and the distribution of species among genera in the Ophichthidae. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.