Isotriphora pardus, Fernandes, 2024

Fernandes, Maurício Romulo, 2024, Triphoridae (Gastropoda) from Martinique sampled by the MADIBENTHOS expedition, with notes on shallow-water species from Guadeloupe, Zoosystema 46 (18), pp. 457-503 : 468

Isotriphora pardus n. sp.

( Fig. 6 )

urn:lsid:zoobank.org:act:3DD03945-A798-4A99-8AE4-F8DDB7AB51D5

TYPE MATERIAL. — Holotype. Martinique • sh; Presqu’Île de la Caravelle , region ‘Nord Atlantique’; MADIBENTHOS expedition sta. AB562, 14°47’30”N, 60°57’24”W; depth 14 m; MNHN- IM-2000-38597 .

Paratypes. Martinique. MADIBENTHOS. ‘ Nord Atlantique’ • 1 sh; type locality; MNHN-IM-2000-38598. — ‘Sud Atlantique’ • 2 sh; sta. AS409; MNHN-IM-2000-38599. — ‘Nord Caraibe’ • 1 sh; sta. AD280; MNHN-IM-2000-38600 • 1 sh; sta. AD289; MNHN-IM-2000-35480 • 1 sh; sta. AD290; MNRJ 24517 • 1 sh; sta. AB567; MNHN-IM-2000-35481.

TYPE LOCALITY. — Martinique: Presqu’Île de la Caravelle, region ‘Nord Atlantique’; MADIBENTHOS expedition sta. AB562, 14°47’30”N, 60°57’24”W; 14 m.

OTHER MATERIAL EXAMINED. — Martinique. ‘Sud Atlantique’ • 1 sh; sta. AD233; MNHN • 1 sh; sta. AS253; MNHN.

ETYMOLOGY. — As a noun in apposition (not an adjective), the specific name alludes to the leopard [ Panthera pardus (Linnaeus, 1758) ], owing to the habit of the author to name species of Isotriphora after big felines.

DIAGNOSIS. — Shell mottled, with irregular patches varying from white, cream or brown; median spiral cord emerges at fifth whorl of shell, reaching the same size of abapical cord after two whorls.

GEOGRAPHIC DISTRIBUTION. — Only known from Martinique.

BATHYMETRIC DISTRIBUTION. — Recorded depth in Martinique: 10- 74 m.

DESCRIPTION

Shell sinistral, conical, nearly rectilinear profile, up to 4.7 mm long, 1.3 mm wide, length/width ratio 2.6-3.5; adult shells reach at least 2.2 mm in length. Protoconch paucispiral with truncated apex, without clear differentiation from the teleoconch, of 3.0-3.5 whorls, 0.52-0.68 mm long, 0.48- 0.58 mm wide; two nodulose spiral cords, situated at 26- 29% and 65% of last whorl height; faint axial threads only visible at the end of last protoconch whorl. Teleoconch with up to 8.5 whorls; two spiral cords (adapical and abapical) at the beginning, continuous to those of protoconch; median spiral cord emerges at fifth whorl of shell, reaching the same size of abapical cord (adapical one is slightly more prominent) after two whorls; rounded nodules of medium size; 14-17 nearly orthocline axial ribs on eighth whorl of shell; shallow suture, with small sutural cord; subperipheral cord slightly nodulose to wavy, two narrow basal cords, wavy to nearly smooth; supranumerical cords absent; nearly circular aperture, 0.48-0.68 mm long, 0.41-0.68 mm wide, length/width ratio 1.0-1.2; open or partly closed anterior canal, crossed in its base by projection of outer lip, 0.18-0.38 mm long, 0.14- 0.22 mm wide, length/width ratio 1.3-1.7; posterior canal as a small sinus, not detached from aperture. Shell mottled, with irregular patches varying from white, cream or brown; some shells with adapical spiral cord whitish and lighter than other cords on late whorls.

REMARKS

Isotriphora pardus n. sp. shows considerable variation in the adult shell size (2.2-4.7 mm long), in the color pattern (with the adapical spiral cord whitish and lighter than other cords on late whorls of some, but not all, shells) and in the closure of the anterior canal. Isotriphora sp. 1 from Fernando de Noronha Archipelago, Northeast Brazil ( Fernandes & Pimenta 2020), is a much similar species, but having narrower axial patches on the teleoconch; the unknown base of Isotriphora sp. 1 , due to the juvenile condition of all sampled shells, precludes further comparisons.

Figures

FIG. 6. — Isotriphora pardus n. sp.: A, H, J, MNHN-IM-2000-38597, holotype, 4.7 mm; B, MNHN-IM-2000-35481, paratype, sta. AB567, 3.8 mm; C, MNHN- IM-2000-38600, paratype, sta. AD280, 3.2 mm; D, MNHN-IM-2000-35480, paratype, sta. AD289, 3.8 mm; E, K, MNRJ 24517, paratype, sta. AD290, 3.0 mm; F, MNHN, sta. AS253, 2.7 mm; G, I, L, MNHN-IM-2000-38599, paratype, sta. AS409, 2.2 mm. Scale bars: A-G, 1 mm; H, K-L, 200 μm; I, 100 μm; J, 500 μm.