Comments on the proposed conservation of usage of Testudo gigantea Schweigger, 1812 (currently Geochelone (Aldabrachelys) gigantea) (Reptilia, Testudines) 4 (Case 3463)

Publication Type:Journal Article
Year of Publication:2010
Authors:G. B. Pauly
Journal:Bulletin of Zoological Nomenclature
Start Page:78
Date Published:03/2010
Type of Article:Comment
Full Text

I am writing in support of the proposal described in Case 3463 to conserve the name
Testudo gigantea Schweigger, 1812 for the Aldabra tortoise by maintaining a recently
designated neotype and suppressing the name Testudo dussumieri. Such an action would
alleviate any recent confusion and nomenclatural instability that might have arisen
regarding the most appropriate name. This confusion stems from the uncertain species
identity and collection locality of the specimen used in Schweigger’s description; this
specimen lacked individual identification (e.g., an accession number) and was only listed
as being ‘in the Paris Museum.’ Recognising that the type specimen was unknown,
Frazier (2006) designated a neotype for Testudo gigantea to stabilise the nomenclature of
the Aldabra tortoise. Subsequently, Bour (2006) claimed to have found Schweigger’s lost
specimen (MNHN 9554), which he identified as the South American taxon Chelonoidis
denticulata. However, there remains uncertainty as to whether MNHN 9554 is the
specimen examined by Schweigger, in part because this would require misidentifications
by Dumeril and Bibron (1835) who were in contact with Schweigger and who specifically
stated that T. gigantea of Schweigger was not the species that we now call C. denticulata.
Given this uncertainty, taxonomic debates and nomenclatural instability will continue
for the Aldabra tortoise without action by the ICZN. Further, even if MNHN 9554
could unquestionably be identified as Schweigger’s tortoise specimen, under Article 75.6
prevailing usage should be conserved by designation of a neotype. To promote stability
and universality, I support maintaining USNM 269962 as the name-bearing neotype. A
significant advantage of this approach is that it results in continuity of usage of the
nomen gigantea, which has been used for over a century in numerous scientific and
non-scientific writings to reference the extant tortoises from Aldabra Atoll.

Taxonomic Group(s): 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith