Relationships within the genus Myoxocephalus (Pisces: Cottidae) based on morphological and biochemical data using numerical and conventional methods of analyses

Abstract

Systematic relationships within the cottid genus Myoxocephalus are derived, based on morphological and biochemical (muscle myogen, lactic and malic dehydrogenase electropherograms) characteristics. The effects of numerical and conventional taxonomic analyses on the relationships derived from both sources of data are investigated.Comparison of numerical clustering of morphological and biochemical data indicates that the relationships are not comparable. However if the data are combined, the relationships obtained are similar to those based solely on morphological information.Conventional analyses of 45 morphological and 35 biochemical characters yielded similar patterns of relationship. The biochemical ones are, however, notably more conservative and simplified. The two treatments of morphological data and the numerical treatment of combined morphological and biochemical data indicate very similar relationships. However the numerical treatment of biochemical data resulted in completely different affinities.It is nevertheless possible to conclude that where evidence is available from a wide variety of systems within the organism, the two analytical techniques yield similar results. Also the inclusion of a limited amount of biochemical data should not be expected to result in greatly improved or altered systematic conclusions.