84 



Y.I. KANTOR, A. MEDINSKAYA AND J.D. TAYLOR 



Gemmula deshayesii (Doumet, 1839) 

 (Figs 18b, 30f) 



Rhynchodeum and proboscis 



There is a large rhynchodeal sphincter situated slightly to the 

 posterior. The rhynchodeum has a folded epithelium of tall glandular 

 cells for its entire length. 



The proboscis is long, nearly as long as the rhynchodeum. The 

 proboscis walls are medium thick about 15% of total diameter, 

 whilst the walls of the buccal tube are thin forming about 5% of the 

 diameter. The muscles of the proboscis wall are less developed near 

 the tip. There is a small anterior buccal tube sphincter, with a short 

 sac-like enlargement and epithelial pad. A single wishbone radular 

 tooth was held in the enlargement. An large intermediate buccal tube 

 sphincter lies at about five tooth lengths from the mouth. 



Buccal mass and oesophagus 



The buccal mass is short, muscular and uncurved and lies within the 

 base of the proboscis. The buccal lips are medium long and invert- 

 ible. The oesophagus is not elongated between the nerve ring and 

 buccal mass. 



Glands 



Salivary glands are large and acinous with paired ducts. There is no 

 change in the histology of the venom gland to the anterior of the 

 nerve ring. The gland opens into the rear of the buccal cavity by a 

 short ciliated duct. The muscular bulb comprises two subequal 

 layers of circular muscle divided by a connective tissue layer. 



Odontophore and radula 



There a two medium-sized odontophoral cartilages. The buccal sac 

 is medium long. The radula consist of both central and marginal 

 teeth (Fig. 18b) The central tooth is wide and low with a central 

 spine-like cusp. The marginal teeth are wishbone in form, but of the 

 'clothes-peg' type with pointed tips and bifurcated proximal ends. 



CHARACTER ANALYSIS AND RELATION- 

 SHIPS WITHIN THE CRASSISPIRINAE 



Characters and states 



On the basis of the analysis of the thin sections described above and 

 previous work (Taylor et al., 1993) we selected 20 characters with 

 potential for determining relationships between the species studied. 

 These characters and their states are listed in Table 2. Many of these 

 are self explanatory or reference is given to figures which illustrate 

 the various states. However, further explanation of some characters 

 is given below. 

 Character 2. In some species, such as Inquisitor latifasciata and 



Ptychobela suturalis, the proboscis tip may be inverted deeply 



into the buccal tube (Fig. 20). 

 Character 5. In some species there is an epithelial pad of large cubic 



cells in the anterior part of the buccal tube (C. (Gibbaspira) 



dysoni, Fig. 5). 

 Character 7. In many species there is a sac-like enlargement of the 



anterior part of the buccal tube. This is often lined with an 



epithelium of tall cells. The function of the sac is to hold single 



detached radular teeth at the proboscis tip (Fig. 30d). 

 Character 9. Some taxa possess large buccal lips which are often 



capable of inversion into the buccal cavity; in others this was not 



observed. 

 Character 11. In many species there is a sharp bend within the 

 buccal mass (e.g. Fig. 9), while other species show no curvature. 



Table 2 List of characters and states used in the cladistic analysis 



1 . Epithelium of posterior rhynchodeal wall: - glandular; 

 1 - continuous with proboscis wall for less than Vi of the 

 rhynchodeum length; 2 - continuous with proboscis wall for more 

 than Vi of the rhynchodeum length. 



2. Proboscis tip: - not inverted inside; 1 - inverted inside. 



3. Proboscis tip epithelium: - not invaginated; 1 - invaginated. 



4. Proboscis length: - very long (longer than rhynchodeum); 



1 - long (50-100% of rhynchodeum length); 2 - short (less than 50% 

 of rhynchodeum length). 



5. Epithelial pad at tip of buccal tube: - present; 1 - absent. 



6. Anterior buccal tube sphincters (the distance from the sphincter to the 

 mouth opening is less than the radular tooth length): - one; 1 - two; 



2 - absent. 



7. Sac-like enlargement of the buccal tube with tall epithelium: 

 - present; 1 - absent. 



8. Intermediate sphincter of the buccal tube (the distance from the 

 sphincter to the mouth opening is more than the tooth length): 



- absent; 1 - present. 



9. Buccal lips: - large invertible; 1 - large uninvertible; 2 - small; 



3 - absent. 



10. Position of the buccal mass: - posterior to the proboscis base; 



1 - at the proboscis base; 1 - within the proboscis (up to near tip). 



1 1 . Buccal mass shape: - not curved; 1 - curved. 



12. Elongation of the oesophagus between buccal mass and nerve ring: 

 - absent; 1 - present. 



13. Salivary glands: - acinous; 1 - modified acinous; 2 - acinous 

 tubular; 3 - simple tubular; 4 - anastomosing tubular. 



14. Histology of the venom gland anterior to the nerve ring: 

 - unchanged; 1 - changed. 



15. Position of opening of venom gland into oesophagus: 0- into rear 

 part of buccal mass; 1 - into oesophagus behind buccal mass. 



16. Number of muscular layers of the muscular bulb: 0-2 layers; 1-3 

 layers. 



1 7. Orientation of fibres in outer two layers of muscular bulb: 

 - similar orientation; 1 - opposite orientation. 



18. Raddula: central 'tooth': - absent; 1 - central ridges present; 



2 - spinose tooth. 



19. Radula: curved lateral 'teeth': - absent; 1 - present. 



20. Radula: marginal teeth: - Epidirona type; 1 - Inquisitor type; 

 2 - Funa type; 3 - Haedropleura type; 4 - Hindsiclava type; 



5 - Cheungbeia type; 6 - Ptychobela type. 



Character 1 3. During this study we found several distinct morphologies 

 of the salivary glands. Many species possessed the normal acinous 

 type found in most neogastropods. In some species, Cheungbeia 

 robusta and Burchia spectabilis. the appearance is of modified 

 acinous (State 1). Funa Jeffrey 'sii and Antiguraleus morgani have 

 glands consisting of single tubes surrounded by acinous cells; this 

 we refer to as acinous tubular (state 2). Simple tubular glands are 

 found in Haedropleura septangularis and Naudedrillia, these are 

 highly coiled inC latizonata (State 3). Finally, in a number of taxa 

 the salivary glands appear to be made up of a mass of anastomosing 

 tubes (State 4). 



Character 14. In most Crassispirinae, the venom gland becomes 

 ciliated and duct-like anterior to the nerve ring. 



Character 17. The muscle fibres in the outer two layers of the 

 muscular bulb, may either have the same or differing orientations. 



Character 1 8. Although there is no central tooth to the radula in any of 

 Crassispirinae studied, we did observe in two species some low 

 transverse ridges which cross the ribbon (Fig. 14a). We refer to 

 these as transverse ridges. In the outgroup, Gemmula deshayesii, a 

 robust central tooth with a spinose central cusp is present (Fig. 1 8b). 



Character 19. In most crassispirines there are no lateral teeth, but 

 amongst the species we examined, two have paired, low, curved 

 structures which are symmetrical on either side of the mid-line 

 (Figs llc-d). Maes (1983) referred to these structures as 'soft 

 laterals'. It is uncertain whether these structures are homologous 

 with the lateral teeth found in the Drilliidae or other neogastropods. 



