Bull. nat. Hist. Mus. Lond. (Zool.) 59(2): 125-170 



Issued 25 November 1993 



Foregut anatomy, feeding mechanisms, 

 relationships and classification of the 

 Conoidea (= Toxoglossa) (Gastropoda) 



JOHN D. TAYLOR 



Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5 BD 



YURI I. KANTOR 



A.N. Severtzov Institute of Animal Evolutionary Morphology and Ecology, Russian Academy of 

 Sciences, Lenin Avenue 33, Moscow 117071 



ALEXANDER V. SYSOEV 



Institute of Parasitology, Russian Academy of Sciences, Lenin Avenue 33, Moscow 117071 



CONTENTS 



Introduction 125 



Material and Methods 1 26 



Foregut anatomy 126 



Functional morphology of the digestive system and feeding mechanisms in the Conoidea 145 



Relationships of Conoidea 150 



Classification of Conoidea and diagnoses of higher taxa 156 



Acknowledgements 161 



Appendix 1. Description of shell characters used in phylogenctic analysis 162 



Appendix 2. Classification of Recent turrid genera 163 



Refe rences 1 68 



Synopsis. A survey of the anterior alimentary system of species from all the higher taxa of the highly diverse 

 gastropod superfamily Conoidea (including the Turridae. Tercbridae, and Conidae) has revealed a great variety of 

 foregut structure. A series of anatomical characters of the rhynchodeum, proboscis, buccal mass, radular apparatus 

 and foregut glands has been defined and their distribution established amongst the various conoidean families and 

 sub-families. Twelve major types of foregut structure were recognised, which ranged from gastropods with a full set 

 of foregut organs and glands to others in which most of the structures including the radula, venom gland and 

 proboscis are absent. A set of these anatomical characters together with a few shell characters were used in a 

 cladistic analysis attempting to determine relationships amongst the conoidean higher taxa. A classification 

 incorporating the new anatomical data and based partly upon the phylogenetic analysis recognises 6 families and 13 

 subfamilies of Conoidea. New data suggest that the Pervicaciinae and Terebrinae share a common ancestor and 

 there is little evidence to justify familial separation of the Coninae. Some major foregut structures seem to have 

 evolved independently in different clades. Thus, hollow 'hypodermic' radular teeth have been derived indepen- 

 dently in a least five clades; the radular caecum and rhynchodeal introvert have evolved independently in two clades. 

 Several clades also show loss of major foregut structures such as the proboscis, venom gland and radular apparatus. 

 Finally, the 378 genera of Recent Turridae' are placed into the higher taxa recognised in the proposed classification. 



INTRODUCTION 



The prosobranch gastropod superfamily Conoidea (=Toxo- 

 ■glossa), which includes the families Turridae, Conidae, Per- 

 vicaciidae and Terebridae, is extremely diverse, with as many 

 as 679 genera and 10,000 living and fossil species claimed for 

 the Turridae alone (Bouchet, 1990) and Conus with around 

 500 living species, is considered to be the most diverse genus 

 af marine animal (Kohn, 1990). Current classifications of 

 axa within the Conoidea are based almost entirely upon shell 



characters, or upon a combination of shell and radular 

 characters (Turridae-Powell, 1966; McLean 1971; Kilburn, 

 1983, 1985, 1986, 1988; Terebridae-Bratcher & Cerno- 

 horsky, 1987). The Turridae are the most morphologically 

 disparate of the four families with seventeen subfamilies in 

 current use. However, most of these subfamilies are rather 

 poorly defined. Despite the biological interest in the venom 

 apparatus of the group, little is known of the relationships of 

 the Conoidea to other gastropods, of relationships between 

 the families of the Conoidea or of relationships within the 

 constituent families. 



©The Natural History Museum, 1993 



