Laevilitorina hicana 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 : 13

Laevilitorina hicana González-Wevar & Rosenfeld sp. nov.

( Fig. 7 )

Laevilitorina caliginosa L6 – González-Wevar et al. 2022: 1527.

Zoobank registration: zoobank.org: act: 3EF20FE5-7CEF-48A2-B85F-9E1FB7099152.

Material examined

Holotype: MNHNCL MOL-205439 , Hornos Island (− 55.965656°S, − 67.251533°W), Cape Horn, 20 November 2016, collected by Sebastián Rosenfeld.

Paratypes: MNHNCL MOL-205440 ; MNHNCL MOL-205441 .

Description

Shell: Small (maximum shell height 3.73 mm), fusiform, with rounded to almost convex whorls, suture impressed, concave spire profile, apex blunt. Aperture ovoid and ≤ 64% of total H ( Fig. 7A–C ). Macroscopic spiral and axial sculpture absent, but multiple fine growth lines cover shell. Columella smooth, inner lip barely reflected over narrow and shallow umbilicus, outer lip thin, simple, and no evidence of thickening. Teleoconch opaque, but last whorl slightly translucent. Colour dark brown and black with small white spots, irregular in size and position. Operculum corneous. Mature H 3.73– 1.20 mm (H/B = 1.05–1.36, SH = 1.48–1.75 mm) (Supporting Information, Table S6).

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

Radula: Rachidian: five cusps, central cusp long, rectangular, and pointed ( Fig. 7D ). First pair of flanking cusps pointed, outer cusps smaller and pointed. Lateral: five cusps, main cusp long, rectangular, and pointed, accompanied by two smaller pointed outer cusps and two continuously smaller inner cusps. Inner marginal: five cusps, main cusp pointed and rectangular, accompanied by one smaller, pointed outer cusp and three pointed inner cusps ( Fig. 7E ). Outer marginal: 10 or 11 thin and pointed cusps ( Fig. 7F ).

Holotype dimensions: Length 3.73 mm, width 2.74 mm.

Depositories: Holotype MNHNCL MOL-205439 . Museo Nacional de Historia Natural, Chile. Type locality: Hornos Island (− 55.965656°S, − 67.251533°W), Cape Horn, Chile .

Habitat: Rocky intertidal shores of Hornos Island, inside empty barnacle shells ( Fig. 7G ).

Materialstudied: HornosIsland(− 55.965656°S,− 67.251533°W), n = 30.

Etymology: The type locality of this new Laevilitorina species is part of the traditional territory of the Yagán (Yaghan) people. In the Yagán language, the word ‘hica’ means sea.

Remarks: In terms of morphology, this Laevilitorina differs from the other Cape Horn species (L. caliginosa s.s.) by exhibiting a globose shell and by having an aperture that occupies on average ≤ 64% of total shell height (Supporting Information, Table S6). Laevilitorina hicana is morphologically more similar to L. pepita from the Strait of Magellan, but the latter has an even more globose shell and an LA/H ratio of 0.68 ± 0.03. Moreover, L. pepita sometimes has spiral colour bands on the last whorl. The current species is rare: of all the areas we have been able to sample around the Magellanic province, it was recorded only at Hornos island. Laevilitorina hicana , like L. magellanica and L. pepita , can be found inside empty barnacle shells.

Figures

Figure 7. Laevilitorina hicana, Hornos Island, southern South America.Scale bars: 1 mm unless specified otherwise.A–C, shell morphology and coloration of specimens collected from Hornos Island. D–F, radular morphology (SEM), showing a general view (F), lateral view (E), and outer marginal (F). G, distribution of L. hicana at Hornos Island, Cape Horn, southern South America.