Inquisitor armillatus, Stahlschmidt, Peter & Fraussen, Koen, 2014

Stahlschmidt, Peter & Fraussen, Koen, 2014, Two new turrid species (Gastropoda: Pseudomelatomidae) from the Palawan region, the Philippines, Zootaxa 3784 (1), pp. 89-93 : 91-93

Inquisitor armillatus n.sp.

Figures 8–10

Type material. Holotype: MNHN IM- 2000-23316 (15.2 mm), Philippines, Palawan, Roxas, off Green Island Bay, 15– 35 m. Paratype 1: SMF-336430 (12.8 mm), same locality as holotype. Paratypes 2–4: PS- 020260 (15.4 mm, 15.6 mm, 15.9 mm), same locality as holotype. Paratype 5: KF (13.7 mm), same locality as holotype. Paratypes 6–7: ANSP- 454323 (15.4 mm, 15.8 mm), Philippines, Palawan, Cuyo Island, 15– 25 m. Paratype 8: Conchology Inc. (14.8 mm), same locality as paratypes 6–7.

Type locality. Philippines, Palawan, Roxas, off Green Island Bay, 15– 35 m.

Distribution. Only known from the northeastern part of Palawan. So far reported from Green Island Bay (dredged at 15–35 m; type material), Cuyo Island (15–25 m, type material), and Taytay Bay (dredged at 20–25 m; voucher specimens PS- 020292).

Description. Shell fairly small for the genus, up to 19.1 mm in length (specimen from Taytay Bay), b/l 0.34–0.37, a/l 0.36–0.42, narrowly claviform with narrow aperture; 7–8 teleoconch whorls; suture moderately deep, whorls moderately convex, barely shouldered.

Aperture narrowly pyriform with a short, deeply notched siphonal canal. Callus moderately developed, forming a rounded nodule in posterior angle of aperture, not intruding into opening of anal sinus and hence scarcely constricting it. Columella thin, smooth and glossy. Fasciole moderately weak. Outer apertural lip thin, convex in side-view, crenulated, with a well-developed stromboid notch and a moderately deep, openly U-shaped anal sinus, which is directed slightly adapically.

Sculptured by weak axial ribs, intervals about 2–3 times broader than axial ribs; 8–10 on first teleoconch whorl, 11– 12 on penultimate whorl (including varices), the last varix situated about on-third whorl back from lip. Spiral cords on spire whorls moderately wide and gently rounded, with equally wide interstices; a total of 3–5 on first teleoconch whorl to 8–11 on penultimate whorl. Spiral cords on last whorl becoming narrower towards rostrum while interstices becoming gradually wider.

Colour whitish-cream with a light to dark brown spiral band situated above the suture at the abapical part of each teleoconch whorl. Last whorl with two bands, one at the first adapical third and the second one ending at the abapical part of the siphonal canal. Interior of aperture white tinged.

Protoconch narrowly domed, of 2–2.5 whorls, first whorl depressed, second one weakly convex; suture shallow; white tinged, smooth except for very weak growth lines near termination.

No soft parts or operculum available for study.

Remarks. With its remarkable coloration, Inquisitor armillatus n. sp. remotely resembles the South African Inquisitor arctatus Kilburn, 1988 (Figs. 11–13) but the former species attains a much smaller size (around 15 mm compared to around 50 mm), has a shorter siphonal canal, a less pronounced parietal nodule, and fainter spiral cords.

Etymology. The specific name is derived from the Latin expression armillatus meaning “wearing a bracelet” which refers to the dark brown colored spiral band.