Favartia massemini, Merle & Garrigues, 2008

Merle, Didier & Garrigues, Bernard, 2008, New muricid species (Mollusca, Gastropoda) from French Guiana, Zoosystema 30 (2), pp. 517-526 : 524

Favartia massemini n. sp.

( Fig. 7 )

TYPE MATERIAL. — N French Guiana. Continental shelf, holotype ( Fig. 7 ), length: 18.5 mm, diameter: 12 mm, ( MNHN).

TYPE LOCALITY. — N French Guiana.

ETYMOLOGY. — Named in honour of David Massemin.

DESCRIPTION

Protoconch unknown. Biconic shell high of 5 subcarinate whorls (height: 18.5 mm; width: 12 mm). Last whorl (5th whorl) 72% of total length of the teleoconch. Spiral sculpture with thick primary cords. First and 2nd whorls: presence of primary cords P1 and P2. Third whorl: appearance of primary cord IP. Fourth whorl: appearance of secondary cord s2. Fifth whorl: developed IP (sutural ramp), P1 to P5 (convex part of the whorl) atrophied P6, ADP and MP (siphonal canal); secondary cords: s2 more developed than s3 and poorly developed s6. Axial sculpture of imbricate varices. Primary cords spines IP, P1 to P5, ADP and MP slightly developed. Nine varices on 2nd and 3rd whorls, 8 on 4th and 5th whorls. Microsculpture with erected growth laminae, appearing on 4th whorl. Suborbicular aperture 25% of the diameter. Outer lip orthocline, thickened by 8 to 10 growth laminae. Six simple, internal denticles (ID, D1 to D5) which are poorly expressed and slightly extended in the internal part of apertural lip. D6 missing. Shoulder sinus closed by the growth laminae. Parietal lip poorly erected. Columellar lip erected and drawing an inductura. Siphonal canal of 54% of aperture length. Pseudombilicus large.Shell rosy with brown varices. Animal and radula unknown.

INTERSPECIFIC COMPARISONS

Favartia massemini n. sp. may be compared to other close species as F. cellusosa (Conrad, 1846) (Florida, North Caribbean), F.nucea (Mörch, 1850) (Florida, South Caribbean), F. coltrorum Houart, 2005 ( Brazil, Guadeloupe), F. lindae Petuch, 1987 (Florida) and F. pacei Petuch, 1988 (Florida) ( Rios 1985; Petuch 1987; Vokes 1994; Houart 2005). Favartia massemini n. sp. differs from these species in having a shell with more spiny varices, by a more marked shoulder and by a longer siphonal canal. Favartia cellulosa , F. nucea and F. lindae have a more developed s2 (almost of the same thickness as the primary cords). Their growth laminae are more numerous, particularly in the intervarical spaces. The teleoconch whorls of F.pacei are slightly more carinate than in the other species, because of a spiny P1. It differs from F. massemini n. sp. by the lack of other developed cord spines. Favartia coltrorum lacks secondary cords. Favartia massemini n. sp. may be also compared to Murexiella glypa (Smith, 1938) from Brazil (= F. iemanja Petuch, 1979 ) and from the Plio-Pleistocene of Florida ( Vokes 1994). The spire of M. glypta is, however, longer and its cords are always more marked in the intervarical spaces. These last observations show that it is difficult to practically distinguish the genera Favartia and Murexiella Clench & Pérez Farfante, 1945 (type species Murex hidalgoi Crosse, 1869 by original designation), which are very closely related ( Merle 2002).

Figures

FIG. 7. — Spiral sculpture (apertural and dorsal views) of Favartia massemini n. sp., holotype (MNHN). Scale bar: 5 mm.