FOREGUT ANATOMY AND CLASSIFICATION OF CONOIDEA 



159 



Foregut. Proboscis short; buccal mass located near the 

 proboscis tip, odontophore very large and muscular with 

 separate cartilages. Acinous salivary glands small and paired, 

 no accessory salivary gland, no venom apparatus. 



Remarks. This small family possesses unique radular teeth 

 and anatomy, but study of further material is necessary. 



elongated oesophagus between the buccal mass and nerve 

 ring). Moreover, it is also similar to clavatulines in shell 

 characters and in its operculum with mediolateral nucleus. 

 On the other hand, Turricula differs in both shell and 

 anatomical characters from those of other 'Turriculinae'. 

 Thus we transfer this genus, as well as Makiyamaia which has 

 similar characters, to the subfamily Clavatulinae. 



Family Turridae H. & A. Adams, 1853 



Radula always with a membrane with either 3 radular teeth in 

 a row (central being small or weak), 4 (central lost, laterals 

 diaphanous) or with only marginals. Marginal teeth usually 

 wishbone type, rarely enrolled and hollow. Odontophore 

 always present. Radular sac not subdivided into short and 

 long arms. Venom gland always present. Salivary glands 

 always acinous. Accessory salivary gland either present or 

 absent. Operculum present. 



Subfamily Clavatulinae Gray, 1853 



Shell medium-sized (usually 15-30 mm, maximum 60 mm), 

 variable in form. Anterior canal moderately long, sometimes 

 short or trun-cated. Whorls usually adpressed below the 

 suture. Anal sinus located on the shoulder slope, rather deep 

 but sometimes indistinct. Protoconch smooth, of 1.5-3 

 whorls. Axial sculpture predominates or the sculpture is 

 subobsolete and the shell surface is glossy. Operculum ovate, 

 with medio-lateral nucleus. Egg capsules lens-shaped, verti- 

 cally orientated, without an operculum. Capsules attached to 

 the substratum by a stalk on the edge. 



Radula. Strong radular membrane with 3 to 2 teeth in each 

 row. Central tooth with large, very thin, inconspicuous, basal 

 plate and centrally thickened area with a single cusp. Central 

 tooth sometimes absent (Toxiclionella s.s.). Lateral teeth 

 absent. Marginal teeth usually robust wishbone type; hollow 

 harpoon-shaped and barbed in Toxiclionella. 



FOREGUT. Epithelium of posterior rhynchocoel not glandu- 

 lar and continuous with proboscis. Moderately long proboscis 

 with 1 or 2 anterior buccal tube sphincters. Protrusive lips of 

 the buccal tube may be present (Turricula). Buccal mass 

 distal except Clavatula diadema in which it is basal but lies 

 within the proboscis. Odontophore medium to small in size, 

 cartilages unfused (except in Toxiclionella). Salivary glands 

 acinous, usually paired. Single salivary duct in Clavatula 

 caerulea. Single accessory salivary gland in Toxiclionella. 

 Anterior venom gland ciliated. Oesophagus elongated 

 between buccal mass and nerve ring. 



Remarks. Some species in this subfamily possess hollow 

 'toxoglossate' radular teeth associated with strong radular 

 membrane, sometimes, with central teeth. The anatomy and 

 conchological characters of 'toxoglossate' clavatulines are, 

 however, quite similar to those of "nontoxoglossate' ones. 

 Thus at present we do not consider the appearance of 

 hollow teeth in Toxiclionella to be a taxonomic character of 

 subfamilial importance and therefore follow Kilburn (1986) 

 in classifying Toxiclionella with other clavatulines. 



The genus Turricula Schumacher, 1817 appears very simi- 

 lar to clavatulines in both radular characters and anatomy 

 (the distal buccal mass, ciliated anterior venom gland, 



Subfamily Crassispirinae Morrison, 1966 



Shell of medium to small size (usually 10-20 mm, sometimes 

 up to 70 mm), claviform to fusiform. Anterior canal usually 

 short. Anal sinus on the whorl shoulder, parietal callus above 

 the sinus often well developed. Spiral and axial sculpture 

 often strong. Protoconch usually paucispiral, initially smooth, 

 later sometimes with axial (rarely spiral) folds. Operculum 

 with terminal nucleus. 



Radula. Strong radular membrane and 4, 3 or 2 teeth in 

 each row. Central tooth when present (Turridrupa) is thin, 

 quadrate and unicuspate, lateral teeth usually absent but 

 weak and vestigial in Crassispira and Crassiclava. Marginal 

 teeth, robust wishbone type or long flat teeth with a slender 

 accessory limb. Ptychobela has hollow teeth formed from two 

 components. 



FOREGUT. Proboscis moderately long with two anterior buc- 

 cal tube sphincters. Epithelium of posterior rhynchocoel 

 continuous with proboscis (Funa latisinuata). Buccal mass 

 situated at the proboscis base in its contracted state. Odonto- 

 phore medium to small, with fused cartilages. Salivary glands 

 acinous, fused, ducts paired. Anterior venom gland ciliated in 

 some species. Oesophagus elongated behind buccal mass in 

 some species. 



Remarks. This most large and diverse subfamily of Turridae 

 is defined chiefly on shell and radular characters (i.e. rather 

 small claviform shells with wishbone radular teeth). Data on 

 the anatomy of its representatives are still unsufficient to 

 decide certainly whether the subfamily is of mono- or poly- 

 phyletic origin. 



Subfamily Cochlespirinae Powell, 1942 



Shell of medium to large size (usually 20-40 mm, up to 100 

 mm), narrow to broadly fusiform or pagodiform. Anterior 

 canal moderately elongate, rarely short or very long. Sculp- 

 ture variously developed, often with smooth shoulder, and 

 usually with rather short axial ribs below the shoulder, and 

 spiral riblets. Anal sinus usually deep, situated on the shoul- 

 der (sometimes on its lower part). Protoconch usually multi- 

 spiral, smooth or, sometimes, initially smooth and carinated 

 or spirally or axially lirate on subsequent whorls. Operculum 

 with terminal nucleus. 



Radula. Strong radular membrane, with three, four? (see 

 discussion of radula p. 135) or two teeth in each row. Central 

 tooth weak, unicuspid or absent. Marginal teeth of robust 

 wishbone type. 



Foregut. Proboscis usualy long, with one or two anterior 

 buccal tube sphincters. Buccal mass basal, muscular buccal 

 lips may be present or absent. Odontophore small, cartilages 

 4, 2 or absent, fused or separate. Salivary glands acinous. 



