Serrata cylindrata, Boyer, 2008

Boyer, Franck, 2008, The genus Serrata Jousseaume, 1875 (Caenogastropoda: Marginellidae) in New Caledonia, Mémoires du Muséum national d'Histoire naturelle 196, pp. 389-436 : 407-408

Serrata cylindrata n. sp.

Fig. 25

TYPE MATERIAL. — Holotype (lv) MNHN 20605 and 1 paratype (dd) MNHN 20606 .

TYPE LOCALITY. — Norfolk Ridge , 23°18’S, 168°05’E, 305-310 m [SMIB 8: stn DW 190] .

MATERIAL EXAMINED. — Norfolk Ridge. SMIB 8: stn DW 190, 23°18’S, 168°05’E, 305-310 m, 1 lv (holotype, Fig. 25) and 1 dd (paratype) .

DISTRIBUTION. — Antigonia Bank, northern Norfolk Ridge , live and shells in 305-310 m.

FIGS 17-32. 17, 18, Serrata aureosa n. sp.; 17, holotype MNHN 20597, southern New Caledonia, BATHUS 2 stn DW 721, H 6.05 mm; 18, southern New Caledonia, BIOCAL stn DW 46, H 6.05 mm. 19, 20, Serrata dentata n. sp.; 19, holotype MNHN 20599, southern New Caledonia, BATHUS 2 stn DW 719, H 6.90 mm; 20, paratype MNHN 20600, same data, H 6.35 m. 21, 22, Serrata lifouana n. sp.; 21, holotype MNHN 20601, Loyalty Ridge, BIOGEOCAL stn DW 307, H 4.25 mm; 22, Loyalty Ridge, MUSORSTOM 6 stn DW 392, H 3.15 mm. 23, Serrata fusulina n. sp., holotype MNHN 20602, southern New Caledonia, BIOCAL stn DW 33, H 4.50 mm. 24, Serrata procera n. sp., holotype MNHN 20603, southern New Caledonia, BIOCAL stn DW 44, H 4.50 mm. 25, Serrata cylindrata n. sp., holotype MNHN 20605, Norfolk Ridge, SMIB 8 stn DW 190, H 3.90 mm. 26, Serrata coriolis n. sp., holotype MNHN 20607, Loyalty Ridge, BIOGEOCAL stn DW 307, H 5.00 mm. 27, 28, Serrata exquisita n. sp.; 27, holotype MNHN 20608, northern New Caledonia, BATHUS 4 stn DW 918, H 4.80 mm; 28, paratype MNHN 20609, same data, H 5.15 mm. 29, 30, Serrata hians n. sp.; 29, holotype MNHN 20610, Norfolk Ridge, BERYX 11 stn DW 35, H 8.50 mm; 30, southern New Caledonia, BIOCAL stn DW 36, H 9.85 mm. 31, Serrata cf. hians n. sp., southern New Caledonia, BIOCAL stn DW 33, H 8.85 mm. 32, Serrata amphora n. sp., holotype MNHN 20612, southern New Caledonia, BIOCAL stn DW 36, H 8.70 mm.

DESCRIPTION. — Shell very narrow and slender, cylindrical, thin, translucent. Protoconch paucispiral, wide, slightly dome-shaped, smooth. Spire short, blunt, whorls very weakly convex. Aperture very narrow, subvertical, hardly widening posteriorly. Base moderately tapering. Outer lip very thin, straight, vertical, shoulder moderately sloping, narrowly rounded, outer margin narrow, slightly thickened, bevelled, slightly stepped, inner lip bearing indistinct denticles on central and lower areas, 5 very small denticles on upper part. Four thin columellar plaits, lower one slightly angular, oblique, second one oblique, more curved, 2 upper ones less oblique, decreasing in size posteriorly.

Ground colour pale orange, 3 wide orange bands evenly spaced on last whorl and the outer margin, suprasutural zone intense white.

Dimensions: 3.90 x 1.35 mm.

Radula unknown.

REMARKS. — Serrata cylindrata is similar to the syntopic S. minima in its short, blunt spire, its angled anterior columellar plait, and its straight outer lip with the smallest denticles on the anterior area and the largest denticles on the posterior part. It differs from S. minima principally in its narrow and slender shell outline, its more oblique anterior columellar plait and its very thin outer lip. The 3-banded colour pattern of S. cylindrata is more closely similar to that of S. boucheti than that of S. minima . The geographical range of S. cylindrata is close to those of S. minima and S. ovata . Serrata cylindrata is sympatric with both S. minima and S. bathusi on the Antigonia Bank.

ETYMOLOGY. — Latin cylindratus (adj., cylindrical), referring to the cylindrical shape of the shell.

Serrata coriolis species group