PHYLOGENETIC-RELATIONSHIPS OF THE CREEK CHUBS AND THE SPINE-FINS - ANENIGMATIC GROUP OF NORTH-AMERICAN CYPRINID FISHES (ACTINOPTERYGII, CYPRINIDAE)

Phylogenetic analyses based on the complete nucleotide sequence of the mitochondrial 12S ribosomal RNA gene were performed for representativ es of major North American cyprinid clades. These analyses resolved fo ur monophyletic groups: (1) Western Clade, represented by Acrocheilus and Gila, (2) Creek Chub Clade, represented by Couesius, Hemitremia, S emotilus, and Margariscus, (3) Open Posterior Myodome Clade, represent ed by Campostoma, Phenacobius, Cyprinella, Notropis, Platygobio, and R hinichthys, and (4) Plagopterin Clade, represented by Snyderichthys, L epidomeda, and Meda. The overall results of these analyses refute prev ious hypotheses of relationships of North American Cyprinidae based on morphological data. Our analyses support recognition of Snyderichthys , formerly considered a subgenus of Gila, and indicate that the Plagop terin Clade is sister to the Creek Chub Clade. Furthermore, this analy sis indicates that hypotheses of relationship between plagopterins and other Western taxa are unsupported and the Open Posterior Myodome Cla de is a monophyletic group. (C) 1997 The Willi Hennig Society.