Laevilitorina pepita González-Wevar & Rosenfeld, 2023

Rosenfeld, Sebastián, Segovia, Nicolás I, Maturana, Claudia S, Aldea, Cristián, Saucède, Thomas, Brickle, Paul, Spencer, Hamish G, Poulin, Elie & González-Wevar, Claudio A, 2023, A revision of the higher latitude periwinkle species Laevilitorina caliginosa sensu lato, Zoological Journal of the Linnean Society 202 (1), pp. 1-18 : 8

Laevilitorina pepita González-Wevar & Rosenfeld sp. nov.

( Fig. 4 )

Laevilitorina caliginosa L3 – González-Wevar et al. 2022: 1527.

Zoobank registration: zoobank.org:act: C823DE09-7B80-427F-A2E9-2CE096719C69.

Holotype: MNHNCL MOL-205429 , ~ 25 km north of Punta Arenas (− 52.987406°S, − 70.812342°W), Strait of Magellan, 21 June 2015, collected by Claudio González-Wevar and Sebastián Rosenfeld.

Paratypes: MNHNCL MOL-205430 ; MNHNCL MOL-205431 ; MNHNCL MOL-205432 ; MNHNCL MOL-205433 .

Description

Shell: Small (maximum length 3.8 mm), fusiform with rounded to convex whorls, suture impressed, concave spire profile, apex blunt. Aperture ovoid, between 66% and 73% of total H ( Fig. 4A–C ; Supporting Information, Table S3). Multiple fine growth lines, sometimes with soft spiral colour bands on the last whorl ( Fig. 4A ). Columella smooth, inner lip barely reflected over narrow umbilicus, outer lip thin, simple, and with no evidence of thickening. Teleoconch opaque, but last whorl slightly translucent. Colour very variable: creamy, pale brown, brown, and olive green. Some individuals have small white spots, irregular in size and position. Operculum corneous. Mature H 2.4–3.8 mm (H/B = 1.01–1.09, SH = 1.39–1.54) (Supporting Information, Table S3).

External anatomy: Ventral area of foot orange, cephalic area black.

Radula: Rachidian: seven cusps, central cusp long, rectangular and pointed ( Fig. 4D, E ). First pair of flanking cusps pointed; outer cusps much smaller, pointed or rounded. Lateral: five or six cusps, main cusp rectangular and pointed, accompanied by one smaller pointed outer cusp and three continuously smaller inner cusps. Inner marginal: six cusps, main cusp pointed and rectangular ( Fig. 4F ), accompanied by one smaller pointed outer cusp and four pointed inner cusps of similar size. Outer marginal: seven or eight thin and pointed cusps.

Holotype dimensions: Length 3.73 mm, width 3.17 mm.

Depositories: Holotype MNHNCL MOL-205429 . Museo Nacional de Historia Natural, Chile. Type locality: Chabunco (− 52.987406°S, − 70.812342°W), Strait of Magellan, Chile ( Fig. 4G ).

Habitat: Rocky intertidal to subtidal shores at the northern side of the Strait of Magellan ( Fig. 4G ).

Material studied: Faro San Isidro , Strait of Magellan (− 53.785572°S, − 70.973522°W), n = 30; Port Famine , Strait of Magellan (− 53.699404°S, − 70.931500°W), n = 80; Punta Carrera, Strait of Magellan (− 53.586367°S, − 70.923372°W), n = 50; Leñadura, Strait of Magellan (− 53.213428°S, − 70.938350°W), n = 20; Chabunco, Strait of Magellan (− 52.987406°S, − 70.812342°W), n = 60; Possession Bay, Strait of Magellan (− 52.232083°S, − 69.297419°W), n = 20.

Etymology: The morphology of L. pepita resembles a small seed = ‘pepita’ in Spanish.

Remarks: Among the Strait of Magellan species, L. pepita exhibits the most distinct morphology and coloration ( Fig. 4A–C ). This taxon exhibits a great variability of shell coloration, with the presence of spiral colour bands. It has a very short spire, and the last whorl is more globose than in the other South American Laevilitorina species. The radula of L. pepita is similar to that of L. magellanica , but the latter may exhibit denticles on the main cusps of the lateral and marginal teeth. This species, like L. magellanica , inhabits the intertidal zone and is also found in empty shells of the barnacle Notochthalamus scabrosus (Darwin, 1854).

Figures

Figure 4. Laevilitorina pepita, Chabunco, Strait of Magellan, southern South America.Scale bars: 1 mm unless specified otherwise.A–C, shell morphology and coloration of specimens collected at Chabunco, Strait of Magellan. D–F, radular morphology (SEM), showing a general view (D), rachidian (E), and inner marginal (F). G, the distribution of L. pepita in the Strait of Magellan.