Helix companyonii
Creators: name: Altaba, Cristian R.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Stylommatophora
Helicidae
Helix
Helix companyonii

description: Helix companyonii is an available name
Outside the Serra de Tramuntana, throughout most of Mallorca one can find the much smaller Iberellus, readily separated from the “caragol de serp”; these have an even more complicated nomenclature history (Forés, 2004a, b; Altaba, 2007a, b). The first mention of this lowland species refers, quite remarkably, to French Catalonia,where it was likely introduced when that part of the continent belonged to the Kingdom of Mallorca in the late Middle Age. The finding was made public in 1837 at the Société Philomatique de Perpignan, where the naturalist Louis Companyo presented a collection of land snails of the Department, perfectly ordered and labeled, assembled by J. Aleron. The latter had found a new species which he called Helix Companyonii in honor of his friend and mentor (Companyo, 1837). This collection has been on public display ever since (Bourgat & Belledent, 1983; Bourgat, 1994). Moreover, Companyo himself took care to ensure that any interested colleagues would receive specimens of the new species. Thus, there has never existed any doubt about the identity of this species.
The obvious problem is that throughout his brief address to the enlightened scientific society, Companyo (1837) failed to point at even a single diagnostic trait; he only stated: “Cette espèce se rapproche beaucoup de l’ helix serpentina et ondulata; nous ne pouvons asseoir encore notre jugement, cependant nous pensons qu’elle n’a pas été décrite” [This species much resembles Helix serpentina and H. ondulata; we cannot still settle our judgement, yet we think it has not been described.]. This description is so poor that it might qualify as a nomen nudum (Hidalgo, 1878, 1890, 1918; Jaeckel, 1952; Paul, 1982a, 1982b, 1985; Paul & Altaba, 1992; Alonso-Zarazaga, 2004; Welter-Schultes, 2012; Chueca et al., 2013). Another interpretation is that of Chueca et al. (2013), who claim the abovementioned sentence is an explicitly negative will to publicize the species; this view has no grounds and is anyway irrelevant for old literature. What Companyo (1837) did was to mention the name proposed by his friend Aleron. However, he did so provisionally, considering it as a synonym. So he did not provide a description such as to make the name available, but neither did he propose a simple nomen nudum. Such synonymy can be inferred to affect the first species mentioned: H. serpentina Férussac, 1821. This is now included in the genus Marmorana Hartmann, 1844, distributed across the Tyrrhenian region (Giusti et al., 1995).
Thus, as soon as someone used the name mentioned in synonymy by Companyo (1837), the name H. companyonii Companyo, 1837 was rendered available (Articles 11.6.1 and 50.7 of the Code). This already occurred in the work by Dupuy (1848, plate published in 1847, by installments), where the species is described in great detail under this name and correctly attributing it to Companyo. Dupuy (1847: xxvi) acknowledges having received from Companyo “les espèces les plus rares des Pyrénées Orientales” [the rarest species of the Eastern Pyrenees]. Later on (Dupuy, 1848: 120, 121) he quotes a letter from Companyo dated in 1847. Moreover, Dupuy examined the two specimens in the collection prepared by Aleron and labeled them as types (Forés, 2004b).
A fact worth mentioning is the virtual —perhaps real— extinction of Iberellus companyonii from its type locality (Altaba, 2007b). It is still mentioned from the vicinity of Banyuls de la Marenda (Banyuls-sur-mer), albeit every time as less common, by various authors throughout the 19th century (Drouet, 1855; Companyo, 1863; Massot, 1872; Locard, 1882, 1894; Granger, 1884). At the onset of the 20th century its existence in France was deemed doubtful (Germain, 1929, 1930). It has probably been extinct in France for over one hundred years; it is thus absent from a widely used field guide to the land snails of northwestern Europe (Kerney et al., 1999), as well as from a proposal of species in need of protection in the Languedoc-Roussillon region (Bertrand, 2004). However, it is unclear why this species is not even mentioned in a critical review of the terrestrial and freshwater molluscan fauna of European France (Falkner et al., 2002). I. companyonii was locally introduced into other localities on the Catalan coast (mostly the old buildings and fortresses in the cities of Barcelona and Tarragona); today it is almost extinct on the continent, with a last population in the Roman city wall of Tarragona (Servain, 1880; Aguilar-Amat, 1914; Rosals, 1914; Cazurro et al., 1916; Haas, 1929; Gasull, 1964; Cuerda, 1975, 1989; Bech, 1990; Altaba 1991, 1993, 2007b; Paul & Altaba, 1992; Forés 2004a). Perhaps being an allochthonous species it might not deserve any special protection, but such action has actually been asked for in the case of other species locally naturalised along the French and Spanish Mediterranean coastline.
description: Published as part of Altaba, Cristian R., 2022, Nomenclature of Helicidae (Gastropoda: Pulmonata) endemic to the Balearics, pp. 168-186 in Nemus 12 on pages 173-174, DOI: 10.5281/zenodo.12170426