Conomodulus Landau, Vermeij & Reich, 2014

Lozouet, Pierre & Krygelmans, Anouchka, 2016, A new species of Indo-Pacific Modulidae (Mollusca: Caenogastropoda), Zootaxa 4103 (2), pp. 195-200 : 196-198

Conomodulus Landau, Vermeij & Reich, 2014

Type species: Modulus preangerensis K. Martin, 1905 (by original designation); Miocene, Java, Indonesia.

Conomodulus neocaledonensis sp. nov.

( Figs. 2 D, 3, 4)

Type material (Recent). Holotype [MNHN-IM-2000-31117, figs. 2D, 3, 4D–I], dimensions: SL= 8.7 mm, SD= 7.7 mm, SWL= 6.8 mm; paratype [MNHN-IM-2000-31116, fig. 4A–C], dimensions: SL= 7.5 mm; SD= 6.8 mm.

Type locality. New Caledonia, Ouen Island, Baie du Prony [Lagon program, St. 243, 22°24 S, 167°01 E].

Etymology. From its type locality.

Description. Shell small, solid, shouldered, turbiniform with a pyramidal shape and a relatively tall spire. Protoconch unknown. Teleoconch of more than four whorls, separated by deeply impressed and undulating suture. Sculpture of large rounded axial ribs, almost as broad as the interspaces, and irregular spiral cords. Eleven axial ribs (on holotype and paratype) on penultimate whorl with adapical termination along suture; spiral cords very faint, except four to five stronger cords that are more developed when crossing ribs. Scars on shell subsequent to pronounced and irregular axial growth lines covering body whorl.

Body whorl occupies 78% of total length of shell, shouldered, roundly angular at periphery. Axial sculpture of ten ribs, well-developed on abapical part of whorl, stopping abruptly at periphery of base just at beginning of outer lip. Base straight sided, bearing four to five primary spiral cords, one more keeled below periphery, with spiral threads in interspaces. Umbilicus small, but relatively deep. Aperture large, ovate, with fine callus on parietal wall and siphonal canal represented by broad depression; anal canal not developed. Columella deeply excavated in mid-portion, with welldeveloped callus and strong, abapical columellar tooth. Outer lip, likely sharp, prosocline, regularly rounded; inside of labium smooth.

Taenioglossan radula ( Fig. 3 ). Rachidian tooth with rounded, square, smooth basal plate; central cusp large, pointed, flanked on each side by two smaller cusps. Lateral teeth curved, trapezoidal in shape; with six to seven cusps; first inner two cusps relatively large, following four cusps smaller and tapering in size, outermost seventh cusp very small, barely visible. Marginal teeth long, spatulate with six elongated cusps.

Operculum thin, corneous, circular, multispiral with a tiny central nucleus.

Figures

FIGURE 2. Outlines of recent and fossil Modulidae. A. Indomodulus tectum, New Caledonia, Touho, Montrouzier expedition, sta. 1246, 20 ° 48, 8 ’ S, 165 ° 08.7 ' E [MNHN-IM- 2012 - 36610]. B. Modulus turbinoides (Locard, 1897) Cape Verde, Calypso 1959, sta. 65, 15 ° 37 ’ N, 23 ° 09 ’ W [MNHN-IM- 2012 - 36609]. C. Modulus modulus (Linnaeus, 1758), Sanibel I., Florida, coll. Staadt [MNHN-IM- 2012 - 36612]. D. Conomodulus neocaledonensis sp. nov., holotype, New Caledonia, Ouen I., Lagon campaign, Sta. 243, 22 ° 24 S, 167 ° 01 E [MNHN-IM- 2000 - 31117]. E. Conomodulus preangerensis (K. Martin, 1905), late Miocene, early Tortonian of Bontang, East Kalimantan, Indonesia (locality TF 505) [RGM. 794.179]. F. Incisilabium parisiensis (Deshayes, 1832), Middle Eocene, Bartonian, Paris Basin, St-Vaast-lès-Mello (Barisseuse), coll. Pacaud [MNHN. F. A 51573]. The arrows indicate the siphonal depression, reinforced in B and C.

FIGURE 3. Radula of the holotype [MNHN-IM- 2000 - 31117] of Conomodulus neocaledonensis sp. nov. A. partial view of the radular ribbon. B. central, lateral and marginal teeth. C. central and lateral teeth.