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Lampreys

  • J. E. Webb
  • J. A. Wallwork
  • J. H. Elgood
Chapter
Part of the Classification Guides book series

Abstract

The first aquatic vertebrates, the Agnatha, which appeared 450 million years ago in the Ordovician period, are represented today solely by the lampreys and hagfishes. Early agnathans were quite different in appearance from the lampreys. Many had a bony armour covering the head and trunk and were dorsoventrally flattened, suggesting a slow-moving bottom-living habit, while others were evidently more active, with bony scales and a slender body. All these ancient fishes had a median pineal eye on top of the head. This is retained in the lamprey, but no trace remains of ancestral bony armour in any present-day agnathan.

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Copyright information

© J. E. Webb, J. A. Wallwork and J. H. Elgood 1981

Authors and Affiliations

  • J. E. Webb
    • 1
  • J. A. Wallwork
    • 1
  • J. H. Elgood
    • 2
  1. 1.Westfield CollegeUniversity of LondonUK
  2. 2.University of IbadanNigeria

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