Comments on snails of the genus Zoniferella from Ecuador (Mollusca: Achatinidae), with restriction of the type locality “Los Puentes” for several species of Gastropoda and Arachnida

The genus Zoniferella includes six taxa of land snails from Colombia and Ecuador for which little has been published beyond their original descriptions. In this paper, we present new records of Zoniferella vespera, a species previously known only from its type locality, expanding its range across northwestern Ecuador. We provide the first description of the colouration in life for Zoniferella snails. We comment on the similarities among some species of Zoniferella, suggesting the possibility that Z. vespera and Z. riveti are junior synonyms of Z. albobalteata, and Z. bicingulata is a synonym of Z. riveti var. bizonalis (as Z. bizonalis). Finally, we offer evidence to allow the restriction of the locality of “Los Puentes”, type locality of Mesembrinis vesperus Jousseaume, 1887 = Zoniferella vespera (Gastropoda: Achatinidae); Isomeria bourcieri lutea Cousin, 1887 (Gastropoda: Labyrinthidae); Guestieria locardi Jousseaume, 1887 (Gastropoda: Scolodontidae); Proserpinella cousini Jousseaume, 1887 (Gastropoda: Proserpinellidae); Idiophthalma robusta Simon, 1889 (Arachnida: Barychelidae); Eurypelma (Lasiodora) augusti Simon, 1889 = Pamphobeteus augusti (Arachnida: Theraphosidae), Eurypelma (Lasiodora) vespertinus Simon, 1889 = Pamphobeteus vespertinus (Arachnida: Theraphosidae).

Photographs of one individual were posted in iNaturalist (Valencia 2021), where initial generic identification was provided. We confirmed the generic and species identification based on information provided by Pilsbry (1906), Jousseaume (1887) and Cousin (1887), and examination of photographs of the holotype (MNHN 2000b). Snails were identified as Zoniferella vespera due to the presence of the following diagnostic characters: shell ovateacuminate, thin, delicate, very glossy, decorated with very thin irregular ridges; 6 whorls; spire long, conic; apex obtuse; aperture oval; peristome simple, acute; columellar margin straight. Shell colouration dark green getting paler towards the apex, with a circular white conspicuous band on the last whorl, and columellar margin whitish (Cousin 1887, Jousseaume 1887, Pilsbry 1906. The new specimen is slightly more globular and smaller than the holotype, but we consider that these differences are due to intraspecific variation (Fig. 2). Zoniferella vespera is most similar to Z. albobalteata and Z. riveti. Zoniferella albobalteata is currently diagnosed from Z. vespera by its smaller length (13 mm vs. 17 mm in the holotype of Z. vespera) and subreflexed columella (straight in Z. vespera) (Dunker 1882, Pilsbry 1906. However, size of snails from Otonga is intermediate between both species, but due to the straight columella we assigned them to Z. vespera. Zoniferella riveti differ from Z. vespera by having 7 whorls, a larger size (21 mm), more slender shape, and twisted columella (Germain 1907(Germain , 1911. Zoniferella riveti var. bizonalis and Z. bicingulata differ from Z. vespera by having two white bands on the last whorl, one of which further continues along the other whorls (one band in Z. vespera, restricted to the last whorl) (Germain 1907, 1911, Fulton 1908. Zoniferella pilsbry is easily separated from Z. vespera by having the lower whorls with narrow spiral bands green alternating with narrow white bands, eight whorls, and longer length (26 mm) (Pilsbry 1906).
Subtle differences in length (13-21 mm), number of whorls (6-7) and columella shape (straight or twisted) have been used to separate Z. albobateata, Z. vespera and Z. riveti. A similar situation is noted between Z. riveti var. bizonalis and Z. bicingulata, and both species were not compared in their original descriptions because they were published a year apart (Germain 1907, Fulton 1908. Based on the data provided in their descriptions and photographs of the holotypes (MNHN 2000a, NHM 2021, they would differ in the number of whorls (6½-7½) and the shape of the second white band (narrower than the first band in Z. r. bizonalis, and the same size in Z. bicingulata). However, these differences could be intraspecific variation of single species, suggesting the possibility that Z. vespera and Z. riveti are junior synonyms of Z. albobalteata, as suggested by Hidalgo (1893c), and Z. bicingulata a synonym of Z. riveti var. bizonalis (as Z. bizonalis). Zoniferella albobalteata is currently known only from its type locality in "humid forests near Pasto, Colombia" (Dunker 1882, Pilsbry 1906), about 180 km N from the known range of Z. vespera, while the type locality of Z. riveti (San Tadeo hill, road to Pachijal) is about 10 km W from the type locality of Z. vespera, and within its distribution range (see below). Unfortunately, the type locality of Z. bicingulata was not specified, cited only as Ecuador (Fulton 1908). Decisions about their formal synonymy would require the direct comparison of type specimens and fresh topotypic material.
The colouration in life of Z. vespera has not been described. Individual of Z. vespera from the Otonga Reserve had the sole and border of foot yellowish cream, dorsal surfaces of foot and head dark purplish, and tentacles bright orange (Fig. 1). This colouration in life is observed in other individuals reported in iNaturalist, with some intraspecific variation observed by some individuals having a whitish or orange band running towards the back from the base to each tentacle, and the tentacles coloured yellowish cream as the border of foot (Fig. 1). The colouration in life of the shell is like the coloration in preservation, but some individuals may look almost black. Photographs reported in iNaturalist of individuals with two bands on the last whorl (Z. riveti var. bizonalis / Z. bicingulata) usually differ by having the tentacles completely dark like the dorsal surfaces of foot and head, except for the eyes that are cream (Fig. 3). However, one individual showing two bands has the same colouration described for Z. vespera (Obando 2020) and another has tentacles completely cream-coloured and a whitish band running towards the back from the base to each tentacle (Stegenga 2022) (Fig. 3). "Los Puentes" is the type locality of several taxa of molluscs and spiders, including Zoniferella vespera (Jousseaume, 1887); Isomeria bourcieri lutea Cousin, 1887; Guestieria locardi Jousseaume, 1887; Proserpinella cousin Jousseaume, 1887; Idiophthalma robusta Simon, 1889; Pamphobeteus augusti (Simon, 1889); and Pamphobeteus vespertinus (Simon 1889) (Cousin 1887, Jousseaume 1887, Simon 1889, Breure 2020). However, the precise position of "Los Puentes" has not been established and some authors became confused by descriptions stating that it was "near Quito", suggesting that Los Puentes was in the inter-Andean valley of Quito. Jousseaume (1887) provided the following information about the type locality of Mesembrinus vesperus (now Zoniferella vespera): "A single example of this species was collected by our colleague, Mr. A. Cousin, in his property of Los Puentes, near Quito". Simon (1889) cited the type locality of Idiophthalma robusta as "Los Puentes, near Quito"; he reported specimens of Linothele longicauda (Ausserer, 1871) and Cyclosternum schmardae Ausserer, 1871-whose type locality is Quito, from "Los Puentes, near Quito" and "Los Puentes…, around Quito". For C. schmardae, Simon (1889) said "we also received it from Los Puentes and Rumipamba, around Quito, by Mr. A. Cousin", implying that, like Rumipamba, Los Puentes was in the inter-Andean valley of Quito.
Most collections from Los Puentes were obtained by Auguste Edouard Cousin (Paris, 1835-Quito, 1899, see Breure 2020, Correoso Rodríguez 2020). Cousin published a single but important academic publication: "Faune malacologique de la République de l'Équateur" (Cousin 1887), where he regularly cited "Los Puentes, near Gualea" when commenting on the distribution of several species (e.g., Cyclophorus esmeraldensis, Mesembrinus visendus, Porphyrobaphe irroratus, Drymaeus petasites, Ammonoceras flora, Psadara selenostoma, Isomeria bourcieri, and Obeliscus cuneus), and said that he found Bourciera helicinaeformis "On the road from Quito to Gualea, towards Hacienda de Los Puentes". Cousin cited "Los Puentes, parish of Calacalí, prov. of Pichincha" in the distribution of Eurytus taylorianus, and "Los Puentes, county of Quito" for Isomeria cymatodes and Cyclotus fischeri. Cousin also provided information about the altitude of Los Puentes, saying that it was "More of less 1500 m" for M. visendus and "about 1500 m" for O. cuneus. Pilsbry (1906) cited the locality as "Los Puentes near Gualea at about 1500 meters… (Cousin)" for O. cuneus, based on the information provided by Cousin (1887). Paul Rivet apparently collected at Los Puentes during his expeditions of the Second Geodesic Mission to Ecuador, since Germain (1907Germain ( , 1911 cited specimens of Bulimus (Porphyrobaphe) irroratus collected by Rivet at "Los Puentes, road of Gualea". Francisco Cousin, son of Auguste Cousin, was friend with Rivet (Jarrín 2021), and probably invited Rivet to the Cousin family's farm at Los Puentes. Breure (2020) reported that the label accompanying the types of Proserpinella cousini said "Los Puentes San Fernandino", however, the photographs of the labels shown that it was written "Los Puentes S. Fernando" and not "Fernandino" (Breure 2020: figs. 31-32). Correoso Rodríguez (2020) mentioned that "Los Puentes" was in northwestern Pichincha and that Auguste Cousin bought the farm in 1866.
Based on the map by Wolf (1892), a bridle path connecting Quito with Gualea started going north across the inter-Andean valley of Quito towards the towns of Cotocollao and Pomasqui, then climbing the western Andean Mountain range through the Casitagua and Pululahua mountain pass towards Calacalí and Nono and running down the western slopes of the Andes towards Nanegal and Gualea (Fig. 4). Los Puentes is mentioned in an executive decree issued by Eloy Alfaro, president of Ecuador, on 14 June 1898 and included in the report presented by Ricardo Valdivieso of the Ministry of Public Works to the Congress of 1899 (Valdivieso 1898). The decree responded to requests submitted by people from the region of Gualea to improve the local bridle path and confirms that the farm Los Puentes was in the parish of Nanegal and on the Quito-Nono-Gualea road: Translation: Art. 1º Repair the bridle path from Gualea to Nono. Art. 2º For this work the owners of rustic estates of the parish of Gualea will contribute, once only, with 7% of the value of their properties. The farms "Chiquilpe" of the parish of Nono and "Los Puentes" of Nanegal, will contribute with the same contribution. During the second half of the 20 th century, sections of the Quito-Nono-Gualea bridle path were the basis for the construction of the Quito-Nono-Nanegalito road and the Calacali-Nanegalito-Puerto Quito highway. "Los Puentes" literally means "the bridges" in Spanish, and there were many bridges in the old bridle path from Quito to Gualea in the 19 th century. However, there is a single locality called "Los Puentes" in the region of the old bridle path and modern road/highway, nowadays classified as a neighbourhood of the parish of Nanegal (IGM 1990, DIPLA n.d., GAD Pichincha n.d.). This locality lies very close to an area where large bridges have been historically built to cross a river junction. About 2 km NE from this locality, there is an area known as "San Fernando Cuatro Hermanos", which would coincide with the locality mentioned for Proserpinella cousini.
Coordinates focus point: 0.045833, -78.674167, radius: 2 km. The newly restricted type locality is described as a circle, with a focus point and a radius to describe the associated uncertainty as a maximum distance from that point within which the locality is expected to be found (i.e., point-radius method, Wieczorek et al. 2004  Extensive habitat changes and loss across Ecuador have most probably threatened and pushed towards extinction several snail species. The montane cloud forests on the northwestern Andean slopes of Ecuador, habitat of Zoniferella vespera, have been deeply affected by deforestation for timber extraction, agricultural expansion, and mining projects, with few oldgrowth forest fragments remaining in the region. Information on the diversity, ecology, and biogeography of terrestrial snails of Ecuador is deficient. Aside from some works by Abraham Breure, Francisco Borrero, Modesto Correoso and collaborators (Breure and Borrero 2008, Correoso Rodríguez 2008, 2010, Borrero and Araujo 2012, Breure and Araujo 2017, Breure 2020, little has been published on the fauna of terrestrial snails from Ecuador in recent years. Supplementary file 1. Known localities of Zoniferella vespera (Jousseaume, 1887) and Z. riveti.