Lilloiconcha lopezi, Araya, Juan Francisco & Aliaga, Juan Antonio, 2015

Araya, Juan Francisco & Aliaga, Juan Antonio, 2015, A new species of Lilloiconcha Weyrauch, 1965 (Pulmonata: Charopidae) from central Chile, Zootaxa 4007 (2), pp. 295-297 : 295-296

Lilloiconcha lopezi new species

Figs. 1 A–1E.

Diagnosis. Shell small, trochoid, slightly wider than high, with elevated spire; nearly five whorls, colored in bands of translucent caramel brown and white. Protoconch with 1.5 whorls, smooth. Teleoconch with about one hundred prosocline ribs (about 23 on last whorl), interspersed with many fine riblets; aperture circular, umbilicus ample and well developed.

Description. Shell small (measuring up to 3.8 mm in width), trochoid, spire slightly elevated, shell height about 0.4 of shell width; with five and a half to six convex whorls. Protoconch clearly differentiated from teleoconch; of about one and a half whorls; almost smooth, sculptured only with very faint spiral threads, most noticeable near the sutures. Teleoconch of about four and a half whorls, sculptured with 96 to 104 prosocline coarse axial ribs, 21–24 of them on last whorl, with interspaces filled by about 15 to 21 slightly raised riblets; very faint irregular nodulae at their intersection with vestigial spiral threads, noticeable especially towards the sutures; suture deep and well-marked; aperture 0.4 of shell height, oval to almost circular; lip simple, callus a mere glaze; umbilicus very ample, deep, of about 0.3–0.4 of shell width; periostracum thin, projecting on the most prominent axial ribs; shell colored with alternating axial bands of translucent caramel brown and white. Animal unknown.

Type material. Holotype: SBNHM 456358, paratypes: SBNHM 452239 (3 specimens), MPCCL 0 1572015 (2 specimens). All the material collected at the type locality by J. F. Araya & C. López, 0 3th February 2014.

Type locality. Los Molles (32º14’ S; 71º31’ W, 31 m), Commune of La Ligua, Region of Valparaíso, central Chile.

Distribution and habitat. Only known from the type locality; the shells were found buried in humus and underneath stones, large boulders and rotten leaves.

Etymology. Named in honor of our friend Christian López (Santiago, Chile).

Remarks. The relationship of the new species with presumptive congeneric species from elsewhere in South America is still unknown; unfortunately all of the material consists only of empty shells and the diagnostic aspects of the anatomy, especially that of the penis, epiphallus and marginal radular teeth, are unknown. Hausdorf (2005) noted that although the protoconch of species in the genus appear to be smooth, it has spiral microsculpture when viewed in detail. This characteristic is apparent in the detail of the unworn sections of Fig. 1 E for the new species. Lilloiconcha lopezi is one of the largest species within the genus Lilloiconcha Thiele, 1927; among the congeneric species, only the Brazilian Lilloiconcha superba (Weyrauch, 1965) can be compared with the new species in size or morphometry; however it differs from Lilloiconcha lopezi in having a more elongated shell, with more whorls, less axial ribs (70 in L. superba and about a hundred in the new species) and a much smaller umbilicus (Miquel et al. 2007). Lilloiconcha tucumana Hylton Scott 1963 , the type species of the genus, found in Tucumán, Horco Molle, northern Argentina, has a higher but comparatively smaller and much narrower shell, with more whorls ( Fernández & Castellanos 1973). The new species differs from Lilloiconcha aysensis Miquel & Barker, 2009 —the only other Chilean species in the genus, described from Puerto Chacabuco, Aysén, about 1470 km from Los Molles—in having a much larger shell with a higher profile, sculptured with fewer and smaller axial ribs and in having an oval to almost circular aperture (which is subcircular and narrower in L. aysensis ). This new species thus extends the distribution in Chile of the genus Lilloiconcha, previously known from the southern regions, to Los Molles, central Chile. Advancing our knowledge of the terrestrial malacological fauna in Chile is of high conservation importance given the ongoing increase in the introduction (or recognition) of nonindigenous or invasive land snails to the country, some of them a direct threat to micromollusks ( Araya 2015). Further sampling in northern or central Chile will probably reveal more snail species to be discovered and described.

Figures

FIGURE 1. Lilloiconcha lopezi n. sp., holotype SBMNH 456358; A: ventral view; B: apical view; C: umbilical view; D: SEM of apical view of paratype SBMNH 452239, E: SEM of protoconch of paratype SBMNH 452239.