Bull. not. Hist. Mus. Lond. (Zool.) 60(1): 39-104 



Issued 23 June 1994 



On Recent species of Spiraserpula 

 Regenhardt, 1961, a serpulid polychaete 

 genus hitherto known only from Cretaceous 

 and Tertiary fossils 



T. GOTTFRIED PILLAI 



Marine Biological Services Division, Department of Zoology, The Natural History Museum, Cromwell 

 Road, London SW7 5 BD 



HARRY A. TEN HOVE 



Universiteit van Amsterdam, Instituut voor Taxonomische Zoologie, Postbus 94766, 1090 GT 

 Amsterdam, Nederland 



CONTENTS 



Synopsis 39 



Introduction 39 



Methods and materials 40 



Terminology 40 



Diagrammatic representations of internal tube structures 41 



Diagnosis of Spiraserpula Regenhardt , 1961 41 



Key to the Recent species of Spiraserpula Regenhardt, 1961 46 



Description of species 49 



Discussion 99 



Acknowledgements 103 



References 103 



Synopsis. A group of Recent serpulid species related to the genus Serpula Linnaeus, 1758, but differing from it in 

 two important characters, is described in this paper. The first is a hitherto undescribed character, namely, the 

 possession of internal tube structures which consist of longitudinal ridges and other structures, the form and 

 arrangement of which, in combination with characters of the worms themselves, served to separate the various 

 species. The second is that the thoracic membranes of the two sides in the worm do not unite ventrally at the end of 

 the thorax to form a flap or apron as in Serpula. These characters are also common to 18 species, including three 

 previously described ones. On the basis of the tube structures, these Recent species can be referred to the genus 

 Spiraserpula Regenhardt, 1961, which was previously known only from fossils (Pillai, 1993). Scissiparity was 

 observed in at least three of its species. A key to the known Recent species of Spiraserpula and a discussion on the 

 systematics of the genus are included. 



INTRODUCTION 



In the course of a study of the serpulids currently referred to 

 the genus Serpula Linnaeus, 1758, it was observed that the 

 worms of larger species could frequently be extracted undam- 

 aged from the anterior ends of their tubes with a pair of fine 

 forceps, while they were invariably damaged in the process in 

 certain small species as, for instance, in the well-known 

 Mediterranean species Serpula massiliensis Zibrowius, 1968. 

 In almost every collection of the latter, the worms which had 

 been previously extracted from their tubes were incomplete 

 posteriorly, and the ends of their longitudinal musculature 



provided evidence of their having been forcefully broken off 

 from the rest of the abdomen. The cause of the difficulty in 

 extracting complete worms was revealed by opening their 

 tubes carefully from their anterior ends all the way to their 

 posterior ends. It was found that the posterior end of the 

 abdomen was retracted very tightly into the posterior coiled 

 part of the tube and, quite surprisingly, against a longitudinal 

 row of sharp serrations projecting from the inside of the tube. 

 Examination of more material showed that these were consis- 

 tent for 5. massiliensis. 



Study of similar material from various other geographical 

 localities revealed the existence of species with other forms of 

 internal tube structures. Evidently, these serve for anchorage 



)The Natural History Museum, 1994 



