SPECIAL ICHTHYOLOGY - R. S. Pentyliuk - 2011

1. ORIGIN AND EVOLUTION OF CYCLOSTOMES AND FISHES. SYSTEMATICS OF MODERN CYCLOSTOMES AND FISHES. SUBPHYLUM CRANIATA. INFRAPHYLUM JAWLESS VERTEBRATES (AGNATHA). CLASS CYCLOSTOMATA

Cyclostomes and Fishes belong to the earliest and least complex vertebrate animals (subphylum Vertebrata), reflecting a gradual evolutionary increase in biological complexity from primitive jawless forms (branch or infraphylum Agnatha), which comprise the single Class of cyclostomes (Cyclostomata), to the more advanced cartilaginous (Chondrichthyes) and bony fishes (Osteichthyes).



Last update: 07/08/2026

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