Systematics, zoogeography, and ecology of the Priapulida

Abstract

CONTENTS 1 Introduction 4 1.1 Plan 4 1.2 Material and methods 5 1.3 Acknowledgements 6 2 Systematics 8 2.1 Historical introduction 8 2.2 Phylum Priapulida 9 2.2.1 Diagnosis 10 2.2.2 Classification 10 2.2.3 Definition of terms 12 2.2.4 Basic adaptive features 13 2.2.5 General features 13 2.2.6 Systematic notes 25 2.3 Key to the taxa 26 2.4 Survey of the taxa 29 Priapulidae 29 Priapulopsis 30 Priapulus 51 Acanthopriapulus 60 Halicryptus 62 Tubiluchidae 70 Tubiluchus 73 3 Zoogeography and ecology 84 3.1 Distribution 84