Otitoma cyclophora (Deshayes, 1863)

Morassi, Mauro, Nappo, Andrea & Bonfitto, Antonio, 2017, New species of the genus Otitoma Jousseaume, 1898 (Pseudomelatomidae, Conoidea) from the Western Pacific Ocean, European Journal of Taxonomy 304, pp. 1-30 : 4-6

Otitoma cyclophora (Deshayes, 1863)

Fig. 1 A–L

Pleurotoma cyclophora Deshayes, 1863: 111 , pl. 12, figs 19–21. Type locality: Réunion Island.

Daphnella crenulata Pease, 1868: 221 , pl. 15, fig. 20. Type locality: Polynesia.

Otitoma ottitoma Jousseaume, 1898: 106 . Type locality Djibouti and Aden.

Mitrellatoma mitra Kilburn, 1986: 682 , figs 97, 101. Type locality: Two Mile Reef, Benguera Island, Bazaruto Archipelago, southern Mozambique, 21°53′ S, 35°26′ E. syn. nov.

Material examined

FIJI ISLANDS: 1 spm, MUSORSTOM 10, Stn CP1366, S of Viti Levu, 18°12.4′ S, 178°33.1′ E, 149– 168 m; 1 spm, MUSORSTOM 10, Stn DW1381, S of Viti Levu, 18°17.8′ S, 177°54.4′ E, 275– 430 m.

SOUTHWEST PACIFIC: 1 spm, MUSORSTOM 7, Stn DW626, Banc Bayonnaise, 597– 600 m.

PHILIPPINES: 1 spm, Mactan Island, 10– 20 m.

MADAGASCAR: 1 spm, Tulear reef, 15– 20 m.

Remarks

This species, the type of the genus Otitoma , has a very broad distribution from the southern Red Sea and Mozambique to Japan, Fiji and Polynesia. Kilburn (2004) selected a neotype from Aden and redescribed the species on the basis of local material from Mozambique. The same author determined Daphnella crenulata Pease, 1868 , described from Polynesia, to have been based on a juvenile specimen of O. cyclophora . Our material ( Fig. 1 A–C, G–L) matches that figured and discussed by Kilburn (2004) in morphological features and is, accordingly, considered as conspecific. Kilburn (1986) introduced Mitrellatoma mitra for a single shell from Southern Mozambique; the taxon was later cited by the same author in his list of species belonging to the genus Otitoma ( Kilburn 2004) , but without a formal discussion of the reassignment. In our opinion, the holotype of Mitrellatoma mitra ( Fig. 1 E–F) is a juvenile specimen that perfectly matches the morphological features of the lectotype of Daphnella crenulata , and the former species is also considered a synonym of O. cyclophora here.

Otitoma cyclophora has previously been considered a littoral species ( Kilburn 2004), but the present records indicate it can also live in deep water (down to 600 m). The available specimen from deep water (Stn DW626) measures 13.7 × 4.0 mm, aperture height 6.4 mm and is the maximum size reported for the species. As already noted by Kilburn (2004), O. cyclophora has a well-developed secondary spiral sculpture of numerous closely-spaced, fine spiral threads ( Fig. 1I ).

Figures

Fig. 1. [next page] A–L. Otitoma cyclophora (Deshayes, 1863). A–B. Philippines, Mactan Island, 10–20 m, 7.5 × 2.67 mm. C–D. MUSORSTOM 10, Stn CP 1366, Fiji, S of Viti Levu, 18°12.4′ S, 178°33.1′ E, 149–168 m, 11.35 × 3.65 mm. E–F. Holotype of Mitrellotoma mitra Kilburn, 1986, S Mozambique, Bazaruto Archipelago, approximately 21°53′ S, 35° 26′ E, 6.4 × 2.3 mm (NMJ4527/ T3287). G–K. Madagascar, Tulear reef, 15–20 m. G. Shell. H. Teleoconch. I. Secondary spiral sculpture of the teleoconch. J–L. Protoconch. L. Microsculpture of the protoconch. — M–S. Otitoma carnicolor (Hervier, 1896). M–N. Specimen from Lifou, 20°55.0′ S,167°05.2′ E, 9–20 m, 7.26 × 2.57 mm. O–S. Specimen from Lifou, 20°53.5′ S, 167°02.7′ E, 12–32 m. P. Teleoconch. Q. Secondary spiral sculpture of the teleoconch. R–S. Protoconch. Scale bars: G, O = 1 mm; H = 500 µm; I–K, P, R–S = 100 µm; L = 10 µm; Q = 50 µm.