Lissachatina fulica (Bowdich, 1822)

(Sinistral Specimen On The Left)

A note and some questions on the taxonomy and nomenclature of the Giant African Snail

by Harry G. Lee

    For most of century following its description, the name Achatina fulica was attributed to Férussac (1821: 49 <http://www.biodiversitylibrary.org/item/41533#page/133/mode/1up>: see Fig. 1). As the reader can see, the Baron did indeed coin the binomen based on material of Mauritian provenance without description or figure but with an indication and mention of three specimens he'd examined. Bequaert (1950: 55 <http://www.biodiversitylibrary.org/item/43478#page/57/mode/1up>) stated that there was "a doubtful reference to Martin Lister's pl. 578, fig. 33." By this he meant that the Baron followed that indication with a "?" as can be seen in Fig. 1. Bequaert declared it a "nomen nudum, not being validly defined." In the literature, including Bequaert (1950), the consensus identification of the 1692 Lister figure (Fig. 2; from my microfiche edition) is A. fulica, and I see no reason to break with convention on this matter. However, the position taken by the Code (ICZN, 1999: Article 72.4.1) is that any bibliographic reference an author "doubtfully attributes to a taxon" cannot be considered a type. What a difference one punctuation mark can make!

    Considering the type locality, where this species had been naturalized by 1803 (Bequaert, 1950: 71), it's rather likely that Férussac had A. fulica of authors before him when he named the species. Nonetheless, Bequaert's determination, essentially based on the technicality of the "?", seems to have influenced subsequent workers, who have generally credited Bowdich (1822: pl. 13, fig. 1; p. 112-113 of the BHL .pdf; see below) as the author. The latter's description consisted of only a figure and plate explanation. Of some further interest is the fact that Bowdich (loc. cit:) attributed Achatina fulica to Lamarck. It seems that the Englishman had access to manuscript material from Lamarck¹ (1822: 129  <http://www.biodiversitylibrary.org/item/26549#page/487/mode/1up>), in which the latter author cited A. fulica Daudeb. (short for André Étienne Justin Pascal Joseph François d’Audebert, Baron de Férussac), referring to the 1821 description reproduced here, as a synonym of A. mauritiana Lamarck. Although it and A. acuta Lamarck (proposed on the same page) are both available names and treated as synonyms of A. fulica Bowdich by Bequaert (1950: 60; 63-65), they appear to date from April, 1822. The Bowdich work was published on or before 25 February (Anon., 1822: 463) and thus has priority.

    On further reflection of the Férussac description, a question arises. How should we regard the three specimens he cited: α, β, and γ? Although his implication is that they were varieties (not typical) of his new taxon, would one or more of them nonetheless qualify as its type(s)? The answer is "no;" Article 72.4.1 of The Code (ICZN, 1999) also excludes specimens the author "refers to as distinct variants (e.g. by name, letter, or number)" from being types. Therefore, despite the fact that two were in a "Muséum" and one in his collection ("Nobis"), their identification cannot bear on the availability of the Férussac name. Consequently any notion of a minor upheaval in Lissachatina nomenclature such as reported for Lissachatina immaculata/panthera, repatriation of la grande agathine, and "Restoration" of Le Baron have been guillotined by The Code.

¹Anachronisms of this sort are not uncommon in the classic literature; see the curious case of Plagioptycha strumosa (Reeve, 1852).

Acknowledgments: The author thanks Paul Callomon (Academy of Natural Sciences [ANSP]) for posing the question that led to this analysis, Dr. Philippe Bouchet (Muséum National d'Histoire Naturel, Paris and ICZN Commissioner) for assistance interpreting The Code, Dr. Gary Rosenberg (ANSP and ICZN Commissioner) for bibliographic and nomenclatorial counsel, and Bill Frank (Jacksonville, FL) for many technical services.

Literature cited:

Anon., 1822. A list of donations to the library and museum of the Cambridge Philosophical Society. Transactions of the Cambridge Philosophical Society 1(2): 461- 464.

Bowdich, T.E., 1822. Elements of Conchology. Part I. Univalves. J. Smith, Paris. Pp. (1)-(78) + ii + 19 pls. w/ facing explanations. <http://archive.org/details/elementsofconcho01bowd>

Bequaert, J.C., 1950. Studies in the Achatininae, a group of African land snails. Bulletin of the Museum of Comparative Zoology 105(1):1-215 + pls. 1-81. Sep. <http://www.biodiversitylibrary.org/item/43478#page/3/mode/1up>

Férussac [A.E.J.P.J.F. d’A.], Baron de, 1821. Tableaux systématiques des animaux mollusques classés en familles naturelles, dans lesquels on a établi la concordance de tous les systèmes; suivis d’un prodrome général pour tous les mollusques terrestres ou fluviatiles, vivants ou fossils. Premiere Partie Tableaux systématiques généraux de l’embranchemant divisés en familles naturelles Deuxième partie (premiere section.). Tableaux particuliers des mollusques terrestres et fluviatiles, présentant pour chaque famille les genres et espèces qui la composent. Bertrand, Paris. [j]-xlvij + [i] + [3]-27 + [3]-110 + [i]. <http://www.biodiversitylibrary.org/item/41533#page/9/mode/1up>

ICZN (International Commission for Zoological Nomenclature), 1999. International Code of Zoological Nomenclature fourth edition. International Trust for Zoological Nomenclature. Pp. xxix + 1-306.

Lamarck, J. B. P. A. de M. de, 1822. Histoire naturelle des animaux sans vertèbres présentant les caractères généraux et particuliers de ces animaux, leur distribution, leurs classes, leur familles, leurs genres, et la citation des principales espèces qui s'y rapportent; précédée d'une introduction offrant la détermination des caractères essentiels de l'animal, sa distinction du végétal et des autres corps naturels; enfin l'exposition des principes fondamentaux de la zoologie. [Première édition] Tome 6 Partie 2. Lamarck, Paris. i-vi + 1-232. April. <http://www.biodiversitylibrary.org/item/26549#page/357/mode/1up>

Lister, M., 1685-1692. Historiae sive synopsis methodicae Conchyliorum. 4 vols. [First edition]. London. pp. 1-1000.

See Assorted Worldwide Terrestrial Species for images of Lissachatina fulica from Micronesia, Samoa, Taiwan, St. Lucia, Ecuador, Barbados and Guadeloupe.