Bathygobius

Abstract: Hermaphroditism has been reported for a small number of gobiid fishes, but the extent of this sexual pattern within the family is not known. Gonad structure was examined in one or more species from twenty-one gobiid genera. No evidence of hermaphroditism was found in the species selected from 14 genera. Laboratory studies supported the conclusion of gonochorism for the examined species in four of them:Asterropteryx, Bathygobius, Gnatholepis, andPsilogobius. Currently, the absence of precursive testicular tissues associated with the ovary in females, in conjunction with no retained ovarian features in the testes of males, appear to be reliable indicators of a gonochoristic sexual pattern in gobiid fishes. Evidence for hermaphroditism was observed in seven genera:Eviota, Trimma, Fusigobius, Lophogobius, Priolepis, Gobiodon, andParagobiodon. Protogyny was experimentally confirmed inE. epiphanes, and the gonad structure in another nine of ten species ofEviota suggested either protogyny or protogynous tendencies. With the exception ofGobiodon andParagobiodon, which exhibited similar gonadal structure, ovarian and testicular structure varied considerably among the hermaphroditic genera examined, both with regard to the configuration and to the degree of development of ovarian and testicular tissues, or testicular tissue precursors. Findings of this study indicate that hermaphroditic gonad structure will prove to be a useful trait in determining evolutionary relationships within the Gobiidae.

Abstract: DURING the early phase of investigations on the production of underwater sound by fishes, Griffin (1950) stated: \"The discovery that a wide variety of underwater sounds are produced by fish and other marine animals has raised many unsolved problems concerning the biological significance of these sounds. Are they purely accidental by-products of other activities, are they used for communication from one animal to another, or do they serve in any way for orientation?\" This, of course, does not exclude the possibility that more than one function can be served by a given sound under different circumstances. As one of the primary steps in the study of these problems, Fish and other workers (1952, 1954) began to

Abstract: Electrophoretic study of 26 gene loci was carried out on Bathygobius soporator from the Atlantic side of Panama, and B. ramosus and B. andrei from the Pacific side of Panama. The most closely related pair is B. soporator and B. andrei. The predicted divergence time is about 2.5 million years, which is in accord with geological evidence on the rise of the Panama land bridge. B. ramosus is the distant member of the trio, about equidistant from the other pair.