156 



J.D. TAYLOR, Y.I. KANTOR AND A.V. SYSOEV 



have an anatomy similar to Pervicacia. 



Although the pervicaciines and terebrines apparently differ 

 considerably in foregut anatomy, they share a a number of 

 characters which suggest a common origin (Table 5). The 

 idea that the Terebrinae and Pervicaciinae were derived 

 separately (Rudman, 1969; Taylor, 1990) is rejected. Charac- 

 ters in common between the two groups are: the elongate 

 multi-whorled shell, the rhynchodeal introvert, and in some 

 species the rhynchodeal septum and accessory proboscis 

 structure. Thus, we propose that the common ancestor of the 

 combined Pervicaciinae and Terebrinae clade would have 

 possessed a rhynchodeal introvert, a proboscis, an odonto- 

 phore, a radula with two solid, sickle-shaped, marginal teeth 

 in each row, a venom gland, a pair of acinous salivary glands, 

 a pair of accessory salivary glands, an accessory proboscis 

 structure and a rhynchodeal septum. 



Species in the Pervicaciinae clade have lost the proboscis, 

 venom gland and accessory salivary glands. In the Terebrinae 

 clade, the solid radular teeth were transformed into semi- 

 enrolled and then hollow teeth. The odontophore was also 

 progressively lost. Species with hollow teeth have developed 

 a radular caecum. Other, more-derived terebrines and possi- 

 bly pervicaciines, have lost virtually all the foregut structures, 

 with the rhynchodeal introvert becoming the main feeding 

 organ (Taylor, 1990). 



Because the radula with solid, sickle-shaped marginal teeth 

 and well developed odontophore, is regarded as one of the 

 least-derived for the Conoidea, we regard the Pervicaciinae/ 

 Terebrinae clade as an early branch from the rest of the 

 Conoidea. If our hypothesis of relationships is correct, then 

 the hollow, barbed teeth, the radular caecum, the rhyn- 

 chodeal introvert, and rhynchodeal septum of the terebrids, 

 have been derived independently of those similar structures 

 found in the Daphnellinae and Clathurellinae. 



Status of Conidae 



Despite the distinctive shell form and high species diversity of 

 the group, we have little anatomical evidence to support the 

 separation of Conus at family-level from other higher turrids. 

 We propose only sub-family status for the group. Every 

 anatomical character-state of the conine foregut is shared 

 with species of Clathurellinae and Conorbinae. Some Conus 

 species possess a snout gland in the rhynchocoel, but this 



organ has been little studied. Conus species also have a 

 distinctive osphradium with the multidigitate leaflets (Taylor 

 & Miller, 1989). However, the detailed structure of the 

 osphradium has been studied in only a few species of Tur- 

 ridae, but at least in some Aforia species (Cochlespirinae) 

 there are similar digitate osphradial leaflets (Sysoev & Kan- 

 tor, 1988). The resorption of the inner shell whorls has been 

 used as a diagnostic character of conines (Kohn, 1990), but 

 the occurrence of this feature has been little studied in other 

 conoideans, although it is present in Benthofascis (Conorbi- 

 nae). 



CLASSIFICATION OF CONOIDEA 



Introduction 



Although many of the subfamilial names (as well as apparent 

 synonyms) currently-used within the Turridae were intro- 

 duced in the 19th or early 20th century, no detailed and 

 well-documented classification was developed in these earlier 

 works. Most authors based their classifications exclusively on 

 shell characters, although Stimpson (1865) used radula data 

 and Fischer (1887) divided the Conoidea into four subfamilies 

 solely by opercular characters. The rather detailed classifica- 

 tion of Casey (1904) who recognised eight tribes within the 

 Turridae (Donovaniini are not conoideans), was based on 

 both opercular and shell characters. 



Thiele (1931) classified turrids into three subfamilies con- 

 tained within the family Conidae, with the Terebridae as a 

 separate family. Diagnoses of the turrid subfamilies mainly 

 consisted of combinations of such characters as 'opercu- 

 late-inoperculate' and 'toxoglossate-nontoxoglossate denti- 

 tion'. This was the first classification where the taxonomic 

 difference between toxoglossate and nontoxoglossate radulae 

 was definitely indicated. An elaboration of this classification 

 was developed by Wenz (1938) who recognised five subfami- 

 lies of Turridae as well as the Conidae and Terebridae. 



The classification of Powell (1942, 1966) provided a great 

 stimulus to conoidean taxonomy, and is used, with modi- 

 fications, by almost all authors concerned with Turridae. 

 Powell recognized nine subfamilies which were based prima- 

 rily on shell characters, although radular and opercular 



Table 5. Comparison of character states between Pervicaciinae and Terebrinae. 



Character 



Pervicaciinae 



Terebrinae 



Shell shape 

 Radular teeth 

 Odontophore 

 Radular caecum 

 Venom gland 



Proboscis 

 Salivary glands 

 Accessory salivary glands 

 Rhynchodeal introvert 

 Rhynchodeal septum 

 Accessory proboscis structure 

 Eyes 

 Operculum 



Multiwhorled 



Solid sickle-shaped 



Present 



Absent 



Absent 



Absent 

 Present 

 Absent 

 Present 



Present in some 

 Present in some 

 Absent in all? 

 Present 



Multiwhorled 



If present, usually hollow enrolled marginals 



Present in some Hastula species 



Present in hollow-toothed forms 



Present in all with radula & proboscis 



absent in others 



Present in all radulate forms 



Present in many species 



Present in some species 



Present 



Present in some 



Present in some 



Present 



Present 



