Adelopoma quasimodo Gargominy sp. nov.

Figs 3, 4, 5

Type locality.

French Guiana, Saül, northeastern foothills of Bœuf Mort mountain.

Type material.

Holotype. French Guiana • 1 dry specimen; Saül, Versant nord de Bœuf Mort, le long du sentier de Grand Bœuf Mort (SAUL 44); 3.64098 ° N, 53.21863 ° W; alt. 300 m; 24 Nov. 2018; OG, SS, ST, BF (PAG & MNHN) leg.; Pied d’arbre à contreforts; MNHN-IM-2012-21233 . Paratypes (7). French Guiana • 1 95 % ethanol specimen; same data as the holotype; GenBank: PQ 629098; Bold: DREAL 176-23; MNHN -IM-2013-75603 • 1 95 % ethanol specimen; Saül, Versant nord-est de Bœuf Mort, le long du sentier de Grand Bœuf Mort (SAUL 37); 3.63555 ° N, 53.21035 ° W; alt. 340 m; 21 Nov. 2018; OG, SS, ST, BF (PAG & MNHN) leg.; Autour d’un arbre à contreforts; GenBank: PQ 629107; Bold: DREAL 373-23; MNHN -IM-2013-75648 • 1 95 % ethanol specimen and 4 dry specimens; same data as preceding; MNHN -IM-2013-75652 and MNHN -IM-2012-21955 respectively .

Other material examined.

French Guiana • 9 dry specimens; Saül, Cascades du Mont Galbao, face nord-est (SAUL 64); 3.60376 ° N, 53.26121 ° W; alt. 320 m; 19 Feb. 2020; BF, AA, OG (PAG & MNHN) leg.; Bordure de cambrouse; MNHN -IM-2018-14065 • 13 dry specimens; Saül, Mont Galbao face nord-est (SAUL 65); 3.59681 ° N, 53.26257 ° W; alt. 503 m; 20 Feb. 2020; BF, AA, OG (PAG & MNHN) leg.; Cambrouse et lianes en forêt; MNHN -IM-2018-14047 • 1 95 % ethanol specimen; same data as preceding; MNHN -IM-2013-76395 • 1 dry specimen; Saül, Mont Galbao face nord-est (SAUL 66); 3.59995 ° N, 53.26697 ° W; alt. 382 m; 20 Feb. 2020; BF, AA, OG (PAG & MNHN) leg.; MNHN -IM-2018-14143 • 1 95 % ethanol specimen; same data as preceding; MNHN -IM-2013-76473 • 5 dry specimens; Saül, Mont Galbao face nord-est (SAUL 68); 3.60018 ° N, 53.25877 ° W; alt. 251 m; 21 Feb. 2020; BF, AA, OG (PAG & MNHN) leg.; Bord de cambrouse, sous lianes; MNHN -IM-2018-14032 • 1 95 % ethanol specimen; same data as preceding; MNHN -IM-2013-76384 .

Diagnosis.

An Adelopoma species of minute size, more ovate than conical, densely ribbed, and with a deep suture.

Description.

Holotype: Shell minute (height 2.0 mm, diameter 1.1 mm), sinistral, thin, elongate, conical in first whorls then cylindrical; colour white, subtranslucent. Whorls 5.2, inflated, strongly rounded, separated by a deep suture. Protoconch 1.5 whorls, smooth; protoconch / teleoconch transition distinct because of change in sculpture; surface of teleoconch with lamellate axial ribs (27 on body whorl) and distinct minute spiral striae between the ribs. Body whorl rounded, ventrolaterally with a distinct bulge through which an inner, palatal, crescent-shaped denticle can be seen. Aperture almost circular; upper insertion of the peristome not descending; peristome continuous but the upper part largely merged to the preceding whorl, double, weakly expanded and thickened; there is a columellar lamella at the bottom of the columella, which can be fully seen only by looking through the aperture (also indistinctly visible in frontal view in the aperture); perforate, umbilicus marked by the continuation of the axial ribs. Operculum unknown.

Paratypes: Operculum ~ 0.5 mm, corneous, concave, almost completely circular in shape, completely transparent and whitish. Body (5) colourless and transparent; except for the ca two first whorls where the light brown odd caesura can be seen by transparency. Eyes black, quite minute, at the base of the tentacles. Tentacles ~ 0.2 mm long, cylindrical, extending upward.

Etymology.

The species is named after Quasimodo, the hunchback character of Victor Hugo’s novel Notre-Dame de Paris, and refers to the bulge on the body whorl. It also reminds one of the catastrophic event of the fire at Notre-Dame de Paris cathedral on 15 April 2019, which occurred during the Trinité collecting trip. Treated as a noun in apposition.

Distribution.

This species is only known from Saül, on the northeastern foothills of both Bœuf Mort and Galbao mountains.

Habitat.

Primary forest, under leaf litter on alkaline soils.

Remarks.

This species shares with Adelopoma peruvianum Hausdorf & Munoz, 2004 the distinct bulge on the body whorl, the presence of a columellar lamella and the distinct perforation which are distinctive characteristics of A. peruvianum according to the original description (Hausdorf and Munoz 2004). It differs from that species, together with Adelopoma brasiliense Morretes, 1954 (unfortunately not mentioned in Hausdorf and Munoz (2004) but the holotype was illustrated by Simone (2006: 46) later) in being smaller, more cylindrical and less conical, the sutures deeper, and with a higher rib density. Hausdorf and Munoz (2004) mentioned that the columellar denticle has been overlooked in other species; the presence of the distinct bulge on the body whorl might also have been ignored because it is hardly visible even if fully developed as in A. quasimodo . Thus the whole genus would need a revision over its large distribution.

We obtained two COI sequences differing by nine mutations. Both are related to one sequence of Adelopoma tucma (Döring, 1884) from Argentina, type species of the genus (p - distance 6.1–6.4 %, GenBank HM 753341; Webster et al. 2012).

The genus Adelopoma is known from Mexico to Peru, northern Argentina (Tucumán), south-eastern Brazil, Venezuela, and Trinidad (Torre et al. 1942; Hausdorf and Munoz 2004; Martins and Simone 2014). Its occurrence in French Guiana is not surprising, but its scarcity is remarkable as it is only known from foothills around Saül, on slopes oriented east-northeast on alkaline complexes. However, it is probable that it has been overlooked and that its range in French Guiana is larger than the Saül area.