Lophiotoma polytropa, (HELBLING, 1779)

LOPHIOTOMA POLYTROPA ( HELBLING, 1779) View in CoL

( FIG. 9E)

Murex (Fusus) polytropus Helbling, 1779: 119 , pl. 2, figs 24, 25.

Pleurotoma fascialis Lamarck, 1822: 93 View in CoL ; – Kiener, 1840: 27, pl. 4, fig. 2.

Lophiotoma (Lophioturris) polytropa View in CoL . – Powell, 1964: 313–314, pl. 244.

Lophiotoma polytropa View in CoL . – Poppe, 2008: 770, pl. 680, fig. 4.

Lophioturris polytropa . – Lozouet & Plaziat, 2008: 134, pl. 31, figs 5–9.

Type material: Murex (Fusus) polytropus , whereabouts unknown; syntypes of Pleurotoma fascialis, MHNG (personal communication of P. Stahlschmidt, not seen).

Type locality: Not stated.

Diagnosis: Shell medium-sized, exceeding 50 mm, thick, turriform, with thick brown periostracum, shell dark-purplish brown. Sculpture of strong spiral elements, with rounded or angulate subsutural cord followed by notably elevated paired and broadly spaced sinus cords. Shell periphery and base with dense elevated cords, similar in size to sinus cords and with intermediate finer ridges. Siphonal canal medium long, nearly straight; aperture rather wide, purplish to greyish inside. Radula ( Fig. 5C) with duplex marginal teeth. Anterior (inner) half solid, lanceolate, slightly asymmetrical, with nearly straight anterior margin and convex posterior margin, dorso-ventrally compressed with sharp lateral cutting edges. In posterior half major and accessory limbs bifurcate at about 45° angle, rather thin. Accessory limb narrowing interiorly, where it fuses with major limb. Central formation absent.

Remarks: The species is rather distinct from all other congeners in having a strong, tightly adhered periostracum and uniformly coloured dark shell.

Pleurotoma fascialis Lamarck, 1822 View in CoL , was considered as a synonym of L. polytropa View in CoL by Powell (1964). Although we have not seen the type material of the species, judging from the illustration of Kiener (1840: 27, pl. 4, fig. 2), the type of Pleurotoma fascialis View in CoL is morphologically similar to the illustration of Helbling and therefore we follow Powell’s opinion. Because the recognition of this species is not an issue, even though we were not able to locate the types of Helbling, we do not designate a neotype for L. polytropa View in CoL .

Distribution: Powell (1964) recorded the species from the Philippines, Moluccas, New Britain and New Caledonia.The species is considered rare. Nevertheless, Lozouet & Plaziat (2008) found it common in the mangrove environments of the lower estuary of the Abatan River (Bohol, Philippines). All the sequenced specimens originated from this locality. The species was successfully recollected several years later in the mentioned biotope (Kantor, Fedosov, unpublished).