Conus papillatus

Conus (Papilliconus) papillatus (Tracey & Craig, 2017)

Diagnosis ⁽¹⁾: Small, up to 10 mm. in height, broadly ovately biconical, height : width ratio 2.0-2.4:1, smooth to faintly spirally striate shells, with some degree of angulation on the whorl periphery ; sinus relatively deep ; protoconch small, somewhat cylindrical compared to the rounded shell profile, with a disproportionally large initial whorl ; colour pattern of c. 14 narrow, dark spiral bands.

Discussion ⁽¹⁾: The type species of Papilliconus appears to have few characters (apart from small size) in common with any other contemporaneous genus, and so a new name at generic rank is indicated. Papilliconus differs from Hemiconus by its ovate shape, mostly smooth surface, papillate protoconch and deeper sinus, and in lacking a beaded collar and peripheral nodules.

Diagnosis of P. papillatus n. sp. : Very small, ovately biconical, more or less smooth shell, with a slight rounded angulation at the periphery; spiral colour bands moderately close and irregularly spotted.

Description of P. papillatus n. sp. : Shell very small, spire 38% of shell height ; protoconch small, papillate, diameter 510 μm., paucispiral of 2 whorls; whorl profile straight or slightly concave above; first teleoconch whorl with small obscure nodules which fuse to form a bluntly subangular swelling overhanging the suture on later whorls, becoming obsolete by the last whorl ; spire whorls more or less smooth although some specimens show 2-3 weak spiral grooves on the upper part; last whorl with regular, faint spiral threads which are seen to correspond to a residual colour pattern, occasionally preserved, of c.14 narrow brown bands on the body whorl bearing rather irregular circular spots like a pearl necklace, the band above the periphery being somewhat wider than the others ; vestigial nodules on the spire whorls also show dark coloration. Body whorl sinuous in outline; sinus rather deep, slightly inequilateral ; outer lip broadly rounded, aperture lenticular ; columella slightly concave.

Holotype of Papilliconus papillatus n. sp. : NHMUK PI TG 26920 (leg. B. CRAIG), Natural History Museum, London.

Holotype 8.5 x 3.5 mm., paratypes up to 9.1 x 3.8 mm.

Type stratum and locality of P. papillatus n. sp. : Late Lutetian, Faluns de Hautteville-Bocage, unit FHB-A, Néhou (Manche).

Distribution of P. papillatus n. sp. : Known only from the type locality.

Etymology of P. papillatus n. sp. : Latin adjective papillatus, nipple-like, referring to the protoconch.

Discussion of P. papillatus n. sp. : The protoconch of P. papillatus shows some resemblance to that of H. lineatus sensu Cossmann & Pissarro (1913, figs. 214 bis-3, non Solander, 1766) although shells of the latter have the usual subsutural beads and spirally corded ornament that characterise Hemiconus.

Papilliconus papillatus Tracey & Craig, n. gen., n. sp.

91a-b. Paratype (91b–protoconch) NHMUK PI TG 26919 (leg. S. TRACEY) Néhou;

92a-c. Holotype (92b with residual colour pattern enhanced) NHMUK PI TG 26920 (leg. B. CRAIG) Néhou ;

93. Paratype NHMUK PI TG 26921 (leg. B. CRAIG) Néhou ;

94. Paratype NHMUK PI TG 26922 (leg. B. CRAIG) Néhou ;

95. Paratype (apical) NHMUK PI TG 26923 (leg. B. CRAIG) Néhou.

Bibliografia Consultata

(1) - Steve TRACEY, Brian CRAIG, Laurent BELLIARD & Olivier GAIN (2017) – “One, four or forty species? - early Conidae (Mollusca, Gastropoda) that led to a radiation and biodiversity peak in the late Lutetian Eocene of the Cotentin, NW France.”