Turris annulata ( Reeve, 1843 )

Li, Baoquan & Li, Xinzheng, 2007, An account of the Genus Turris species (Mollusca: Gastropoda: Turridae) from the East and South China Seas, Zootaxa 1397, pp. 63-68 : 65

3. Turris annulata ( Reeve, 1843) (pl. 1, fig. 4)

Pleurotoma annulata Reeve, 1843 : pl. 5, fig. 35.

Turris fagina Adams and Reeve, Yen, 1941: 238 , pl. 25, fig. 184.

Turris annulata (Reeve) , Powell, 1964: 333, Color pl. 181, fig. 19 & pl. 254; Olivera, 1999: 301, pl. 1, sp. 9 & Pl. X; Vera­Pelez J.L., et al, 2000: pl. 7, figs. 5–7.

Material examined 1 spm, MBM119714 , ECS, 126º 00´E, 27º 30´N, CN V498 B­ 20, 131 m, Jul. 5, 1976, fine sand, collected by AT, collector Fengshan Xu.

Diagnosis Shell large, 72.5 mm in height, spiral cord relatively broad and smooth, suture obvious and deep, sinus narrow and deep. Shell light yellow, without spots and axial streaks.

Habitat 131 m in depth, fine sand sediment.

Range East China Sea; Philippines.

Remarks Powell (1966) proposed a new subgenus Annulaturris in genus Turris for this species. However, after carefully examining the specimen, we found many obvious differences from typical Turris species. First, the sinus is not on a spiral rib immediately above the peripheral carina, while the diagnostic characteristic of genus Turris as defined by Powell (1966) is that the sinus is on a spiral rib immediately above the peripheral carina; second, the spiral cords are relatively smooth and broad over the entire shell surface, and the peripheral cord is not obviously bigger than others, unlike in Turris species ; furthermore, Powell (1966) noted that the radular morphology of subgenus Annulaturis was different from that of other species in the genus Turris .

Olivera (1999) also doubted the taxonomic level of subgenus Annulaturris . He had realized the difference between Turris annulata and other typical Turris species. He mentioned that this species might be in genus Gemmula or be apart of a distinctive transitional group intermediate between Gemmula and Turris . He also suggested that the species might belong to the American genus Polystira because of the similarity of shell structure. In our opinion, although the shell form of this species is similar to that of in genus Gemmula , Polystira and Lophiotoma , it still can be easily separated from them. As defined by Powell (1966), the diagnostic feature of Gemmula is the peripheral keel mostly double, often flanged and always studded with gemmules, often cog­like in vertically studded pairs; sinus on the peripheral carina. Lophiotoma species also have a deep and narrow sinus on the peripheral keel. For genus Polystira , we had no specimen to check, but according to Powell (1966) ’s description and illustration, I can’t affirm the validity of placing this species in genus Polystira . In our opinion, it might be appropriate to upgrade the subgenus Annulaturris to genus level. Unfortunately, because we just have one empty shell, some other diagnostic features, such as the radula and operculum, are not available. So, we still tentatively place this species in genus Turris .