FOREGUT ANATOMY AND CLASSIFICATION OF CONOIDEA 



151 



Table 2. Characters and character states of the foregut and shell used in cladistic analysis. See text for details of foregut characters. 

 * denotes characters where the states were treated as unordered. 



Foregut characters 



1. Rhynchodeal introvert 

 *2. Rhynchodeal sphincter 



3. Accessory proboscis structure 



4. Proboscis 



5. Transverse muscles in rhynchodeum wall 



6. Epithelium of posterior rhynchodeal 

 wall continuous with proboscis wall 



*7. Sphincter at distal end of buccal tube 

 8. 



Sphincter in middle of buccal tube 

 9. Sphincter at base of buccal tube 



10. Buccal tube introvert ('valvule') 



1 1 . Protrusive lips of buccal tube 



12. Position of buccal mass 



13. Connection of radular retractors 

 to columellar muscle 



14. Extensible buccal lips 



15. Septum dividing anterior and 

 posterior areas of the rhynchocoel 



16. Elongation of oesophagous between 

 buccal mass and nerve ring 



17. Salivary glands 



18. Salivary ducts 



19. Type of salivary gland 



20. Accessory salivary glands 



21. Radula 



22. Radular caecum 

 *23. Central tooth 



24. Lateral teeth 



25. Marginal teeth 



*26. Type of solid radular teeth 

 *27. Type of wishbone teeth 

 *28. Type of hollow teeth 

 29. Venom gland 



*30. Connective tissue layer of muscular bulb 



*31. Muscle layers of muscular bulb 



32. Odontophore 



33. Odontophoral cartilages 



Shell and opercular characters 



*34. Shell form 



*35. Number of protoconch whorls 



*36. Sculpture of the protoconch 



*37. Siphonal canal 



*38. Position of the anal sinus 



39. Presence of apertural ornament 



(teeth on the outer lip) 



*40. Number of the teleoconch whorls 



*4 1 . Development of subsutural ramp 



42. Operculum 



43. Position of opercular nucleus 



— absent, 1 — present 



— present anterior, 1 — present posterior, 2 — absent 



— absent, 1 — present 



— present, 1 — absent 



— absent, 1 — present 



— absent, 1 — present 



— absent, 1 — one sphincter, 2 — two sphincters 



— absent, 1 — present 

 — absent, 1 — present 

 — absent, 1 — present 

 — absent, 1 — present 

 — basal, 1 — distally shifted 



— present. 1 — absent 

 — absent, 1 — present 



— absent, 1 — present 



— absent, 1 — present 



— two/one glands present. 1 — glands absent 



— two ducts present, 1 — one duct present 



— acinous, 1 — tubular 



— two/one glands present. 1 — glands absent 



— present, 1 — absent 



— absent, 1 — present 



— robust muriciform, 1 — narrow 2 — broad with central spine 



— comb-like, 1 — absent 



— solid, 1 — wishbone, 2 — hollow, 3 — absent 



— Hat, 1 — curved-pointed, 2 — semi-enrolled (Hastula bacillus) 



— large blade, small accessory limb, 1 — short knife type, equilimbed 



— large base, 1 — thin small base 



— present, 1 — present with changed histology in anterior portion, 2 



— absent 



— present, 1 — absent 



— more or less equal, 1 — outer layer thin, 2 — single layer only 



— present, 1 — absent 



— not fused, 1 — fused 



— fusiform, 1 — coniform, 2 — turreted. 3 — terebriform, 4 



rounded 



— less than two, 1 — more than two 



— absent or very weak, 1 — present 



— not differentiated. 1 — moderate, 2 — long 



— sutural, 1 — shoulder, 2 — peripheral, 3 weak or absent 



— absent, 1 — present 



— less than 4, 1 — from 4 to 8, 2 — more than 9 



— absent, 1 — present 



— present, 1 — absent 



— terminal, 1 — mediolateral 



inadequate. Although anatomical data are available for many 

 terebrids (Taylor, 1990 and unpublished), most of these were 

 eventually excluded from the analysis for the following rea- 

 son. Many of the morphological trends in the Terebrinae, 

 involve partial to total loss of the foregut organs (Taylor, 

 1990); thus many of the characters used in the cladistic 

 analysis were recorded as missing. In our earlier attempts at 

 cladistic analysis, terebrid species tended to appear in rather 

 disparate positions on the cladograms. Consequently, we 

 have used only three species to represent the Terebrinae and 



Pervicaciinae, the taxa being the least-derived known for 

 each group. 



Characters 



We used 43 characters, coded as 101 states in the analysis. Of 

 these, 35 characters concerned foregut anatomy and a further 

 eight, the shell or operculum. The characters and their states 

 are listed in Table 2. Full discussion of the anatomical 

 characters will be found in the section of this paper concern- 



