New species of Muricidae Rafinesque, 1815 (Mollusca: Gastropoda) from the Western Indian Ocean Author Roland, Houart Author Virginie, Héros text Zoosystema 2015 2015-09-30 37 3 481 503 http://dx.doi.org/10.5252/z2015n3a4 journal article 10.5252/z2015n3a4 1638-9387 5156547 urn:lsid:zoobank.org:pub:EDB0C7A2-7B5E-4E39-91CE-B823BB38ACA0 Timbellus goniodes n. sp. ( Figs 6 C-G; 7B) TYPE MATERIAL. — Holotype (dd) MNHN-IM-2000-30006, 3 paratypes MNHN, 1 paratype coll. RH (as listed below). TYPE LOCALITY. — South Madagascar , South of Cap Sainte-Marie, 26°14’S , 45°09’E , 284-286 m [ATIMO VATAE: stn CP3615]. MATERIAL EXAMINED. — South Madagascar . ATIMO VATAE: stn DW3552, South of Faux-Cap, 26°07’S , 45°39’E , 264-280 m , 2 dd ( 1 paratype MNHN-IM-2000-30007, 1 Coll. RH). — Stn DW3553, South of Faux-Cap, 26°08’S , 45°39’E , 280-333 m , 1 dd fragment ( paratype MNHN-IM-2000 30008). — Stn CP3615, South of Cap Sainte-Marie, 26°14’S , 45°09’E , 284-286 m , 2 dd ( holotype MNHN-IM-2000-30006, 1 paratype MNHN-IM-2000-30009). DISTRIBUTION. — Southern Madagascar , 280-284 m (shells only). ETYMOLOGY. — Greek, goniodes , angular. This species is named for the angular shape of the teleoconch whorls. DESCRIPTION Shell medium sized for the genus, up to 23.7 mm in height at maturity. Height/width ratio 1.6-2.0. Slender, narrowlyovate, spinose, lightly built. Shoulder strongly sloping, weakly concave or straight. Milky white or pinkish white. Aperture white. Spire high, acute, with 1.5 protoconch whorls and teleoconch up to six weakly convex, angular, weakly shouldered whorls. Suture impressed. Protoconch small, whorls rounded, smooth, glossy, width 600-650 µm.Terminal lip delicate, thin, weakly raised, weakly curved. Axial sculpture of teleoconch whorls consisting of high, narrow, lamellose varices, each with a long, narrow, open shoulder spine. First whorl with six or seven varices, second with five or six, third with four. From fourth to last teleoconch whorl, three narrow, high, lamellose, webbed varices. Spiral sculpture of low and high, narrow, rounded primary cords. First whorl with P1-P3 of approximately the same strength, second with P1-P3, P2 becoming broader and higher. Third and fourth whorls with shallow, almost obsolete P1, P2 and P3 similar in strength and height, P3 partially covered by following whorl, fifth whorl with very shallow P1 and broad, high, rounded P2 and P3, last whorl with weak P1, more obvious on lamellose, webbed varices, P2 and P3 higher and broader, P4-P6 weak, decreasing in strength abapically, broader on webbed apertural varix. P1 ending as a short, narrow, adapically bent shoulder spine. P2-P6 ending as a shorter, backward recurved, narrowly open spine. Aperture ovate, angular. Columellar lip narrow, flaring, smooth or with two weak knobs abapically, rim partially erect, adherent at adapical extremity. Anal notch moderately deep, broad. Outer lip strongly erect, smooth with six weak or strong denticles within: ID, D1-D5. ID very low, broad, D1-D5 variable in strength and height. Siphonal canal moderately short, broad, weakly abaxially bent and dorsally recurved at tip, narrowly open, with variceal webbing extending to 80- 90% of its length. Operculum and radula unknown. REMARKS Timbellus goniodes n. sp. differs in many ways from the other Indo-West Pacific Timbellus species. From T. fulgens ( Fig. 4P, Q ) living in the same geographical area, T. goniodes n. sp. differs in having a narrower shell with a higher spire, a smaller protoconch (600-650 µm wide vs 1000 µm), a narrower subsutural ramp, strong and relatively broader spiral cords with higher P2 and P3, a more angular aperture and more strongly adapically bent shoulder spines, and chiefly in having four to seven varices on the three adapical teleoconch whorls as opposed to three in T. fulgens . From T. crauroptera ( Fig. 6H ) from New Caledonia , a species that also has upward bent shoulder spines and a more angular aperture, T. goniodes n. sp. differs in having somewhat narrower shoulder spines, more strongly obvious spiral cords, less convex teleoconch whorls without intervariceal varices, a higher spire and variceal webbing extending to almost 80% of the length of the siphonal canal rather than extending to 10 or 20% of its length in T. crauroptera with the additional presence of ADP and MP. Moreover T. crauroptera also has three variceal wings starting at the first teleoconch whorl.