Comments on the proposed conservation of usage of Testudo gigantea Schweigger, 1812 (currently Geochelone (Aldabrachelys) gigantea) (Reptilia, Testudines) 6 (Case 3463) | International Commission on Zoological Nomenclature

Comments on the proposed conservation of usage of Testudo gigantea Schweigger, 1812 (currently Geochelone (Aldabrachelys) gigantea) (Reptilia, Testudines) 6 (Case 3463)

Publication Type:Journal Article
Year of Publication:2010
Authors:Cheke, A
Journal:Bulletin of Zoological Nomenclature
Start Page:79
Date Published:03/2010
Type of Article:Comment
Full Text

The remarkable and impassioned correspondence on the name of the Aldabra
tortoise has thrown up some information that requires further notes to supplement
my earlier submission (BZN 66: 174–176).
1. Matyot (BZN 66: 352–354) has offered evidence to suggest that it is unlikely that
Dussumier collected specimen RMNH 3231, designated as lectotype of Testudo dussumieri
by Bour (2006b), on Aldabra. Although many details of his travels are unclear
(see Laissus, 1973), I am inclined to agree that Dussumier did not visit Aldabra, but this
does not mean the animal did not originate there, nor does it invalidate the name under
the Rules. At that time, when native tortoises in the granitic Seychelles were so reduced
that recorded export to Mauritius had ceased (Toussaint, 1967; Stoddart & Peake,
1979), from 1815 the principal source of tortoises for human consumption on Mauritius
and the granitic Seychelles was Aldabra (Mondini, 1990). Fairfax Moresby (1842,
p.741), writing in 1822, reported ‘Aldabra is annually visited in the favourable monsoons
for the land-tortoise, which are to be found most plentifully. They grow to a large
size, are taken to Mahé or the Mauritius, and sold from one to three Spanish dollars
each’. Some of those taken to the Seychelles were then re-exported to Mauritius.
Théodore Sauzier (1893) (also Stoddart, 1971, Stoddart & Peake, 1979) cited import
from the Seychelles of 3400 tortoises into Mauritius in 1826 alone. The origin of 2600 he
presumed to be Aldabra on the grounds that there were no longer such numbers in the
granitics; the other 800 came directly from Providence. A handwritten footnote by
Sauzier in his own copy of Sauzier (1893) uses further manuscripts to raise the 1826
import total to 4800: 4000 on ships incoming from the Seychelles, 800 direct from
Providence (copy in the Radcliffe Science Library, Oxford). It should be added that, as
George Harrison, the lessee of Providence, was also government agent in the Seychelles,
the Providence shipment could also have originated on Aldabra. Stoddart & Peake
(1979) doubted the aboriginal existence of tortoises on Providence and suggested this
shipment reported by Sauzier may have been marine turtle, but the number seems
excessive for a single haul of Chelonia mydas. Slave ships used the excuse of visiting
Aldabra for tortoises to cover their illegal trade (Scarr, 2000), also actually collecting
tortoises to maintain the story. The slavers were often trafficking to Réunion (McAteer,
2000), and Bour (1981) reported Aldabra tortoises advertised for sale there in 1831 and
1834. Dussumier visited all these islands regularly (Laissus, 1973; Bour, 2006a; Matyot,
BZN 66: 352–354), and could easily have obtained an Aldabra tortoise on any one of
them. He is known to have been in Mauritius in 1825 or early 1826 (Bélanger, 1834) and
visited the Seychelles on the same voyage, which ended in spring 1826 (Laissus 1973)
and not spring 1825 as reported by Bour (2006a). Dussumier was back in the Seychelles
in 1827 and again in April 1828, then back and forth in the Indian Ocean with stops at
Mauritius, Réunion and the Seychelles between 1828 and 1830, before returning to
France in September that year. Paris Museum records show he deposited, inter alia, 11
reptile specimens and 13 live tortoises in November 1827, and 11 chelonians in 1830
(Laissus, 1973), though the last lot was too late to have included the T. dussumieri
lectotype in Leiden, which Gray saw on his visit in 1829 (Bour, 2006a). As an assiduous
collector for the Paris museum he would have ascertained its origin, and it is clear fromthe citations earlier that the provenance of tortoises was well known in the islands.
Matyot (BZN 66: 352–354) argues it would be atypical of Dussumier to collect ‘only a
young tortoise and no other specimen from Aldabra’, but given the ubiquity of living
Aldabra tortoises on the Indian Ocean islands he visited, he probably assumed they
were well enough known as adults, and thus brought back only a juvenile. As Bour
(2006a) has enumerated, he also brought adults of the Aldabran form back from
Anjouan and native forms from the granitic Seychelles. Matyot further speculates that
because of some possible shenanigans in the way Gray acquired specimens, the origin of
this specimen should be disregarded, but a) it was not acquired by Gray for the British
Museum (now NHM), but held in Leiden, and b) why invent the then extremely
obscure (to Europeans) locality of Aldabra if there was no reason to do so? Irrespective
of where the specimen was collected, it has been identified by all who have studied its
morphology as a juvenile Aldabra tortoise (see photos in Gerlach, 2004a; Bour, 2006b)
and has been shown by mtDNA analysis to be an Aldabra-Seychelles tortoise (Austin et
al., 2003); hence it remains a valid lectotype for Testudo dussumieri. The only other
possible origin of Dussumier’s specimen RMNH 3231 would be a native granitic
Seychelles tortoise, rare but not extinct in the mid-1820s, of which Dussumier also
brought back a juvenile (Bour, 2006a). Although the juveniles are similar (as is their
DNA), they are morphologically distinguishable (Bour, 2006a; Gerlach, 2004a), and in
any case the granitic Seychelles forms are generally considered (Austin et al., 2003,
Palkovacs et al., 2003, Rhodin et al., 2009) to be conspecific with those on Aldabra;
even Gerlach (2004a), while treating them as species, conceded that they were probably
only subspecifically distinct. Hence dussumieri is the earliest valid name for the species
as a whole if one accepts that the specimen of Chelonoidis denticulata MNHN 9554 is
the rediscovered type of Testudo gigantea (Bour, 2006b; Bour & Pritchard, BZN 66:
169–174). Those who doubt this identification appear to do so on very weak grounds.
2. It is ironic that the holotype of Testudo gigantea turns out to be a Chelonoidis,
for this brings out an interesting contrast in perception amongst those concerned with
tortoises. Until recently the Galapagos tortoise complex, even more iconic and
endangered than those on Aldabra, was generally known as Geochelone elephantopus,
but has morphed in recent decades into Chelonoidis nigra, apparently without any of
the arguments surrounding the nomenclature of the Aldabran animals—no cases or
discussion in the BZN, or other controversy that I can locate. As Bour (2006b)
pointed out: ‘Following Pritchard (mainly 1996), among some other changes, the
universally used Testudo elephantopus Harlan 1827, a name for the Galápagos
tortoises, was replaced by Testudo nigra Quoy & Gaimard 1824, apparently without
major objection from scientists. On the other hand, Frazier (2006) strongly emphasised
the general instability and chaos regarding the valid name of the Aldabra
tortoise’. Crumly (1982), using morphology, drew attention to the apparent
polyphyly of the broad genus Geochelone, and Pritchard (1984) first drew attention to
the fact that Testudo nigra Quoy & Gaimard, 1824 pre-dated T. elephantopus Harlan,
1927. Even before Crumly’s conclusions were amply confirmed by DNA studies (e.g.
Le et al., 2006), the use of Chelonoidis Fitzinger, 1835 had become frequent, and that
of nigra almost universal. However, the IUCN’s red list still uses Geochelone
( apps/redlist/details/9011/0; accessed online 30/12/2009) despite
the SSC’s Tortoise & Freshwater Turtle Specialist Group (Rhodin et al., 2008; 2009)
using Chelonoidis in their world checklist. CITES used Geochelone nigra as early as1999 without complaint (Charette & Gallegos, 1999). Although the retention of
Geochelone in the IUCN red list may indicate residual conservationist resistance to
name change, there seems to have been no suggestion that changing the Galapagos
tortoise nomenclature was going to destabilise conservation measures or otherwise
cause irretrievable chaos and misunderstandings as claimed by the proponents of
Frazier’s case. It is hard to avoid concluding that issues beyond mere science and
nomenclature are at issue here.
Additional references
Bélanger, C. (Ed.). 1834. Voyage aux Indes Orientales. Zoologie. 535 pp. Arthus Bertrand,
Bour, R. 1981. Histoire de la Tortue terrestre de Bourbon. Bulletin de l’Académie de La
Réunion, 25: 97–147.
Bour, R. 2006a. An unnamed tortoise from the Seychelles Islands. Emys 13(3): 24–30.
Bour, R. 2006b. Identity of Testudo gigantea Schweigger, 1812. Rediscovery of the type
specimen. Emys, 13(4): 12–23.
Charette, R. & Gallegos, F.A.L. 1999. CITES identification guide – turtles & tortoises.
[fragmented pagination] Environment Canada, Ottawa.
Crumly, C.R. 1982. A cladistic analysis of Geochelone using cranial osteology. Journal of
Herpetology, 16: 215–234.
McAteer, W. 2000. Hard times in paradise. The history of Seychelles 1827–1919. 322 pp.
Pristine Books, Mahé, Seychelles.
Mondini, E. 1990. Les tortues géantes terrestres et le choc de l’histoire. Cahiers d’Outre Mer 43:
Moresby, F. 1842. On the Seychelle Islands. Nautical Magazine & Naval Chronicle for 1842:
585–590, 676–682, 739–746.
Pritchard, P.C.H. 1984. Further thoughts on Lonesome George. Noticias de Galápagos, 39:
Pritchard, P.C.H. 1996. The Galápagos tortoises: nomenclatural and survival status. Chelonian
Research. Monographs 1: 1–85.
Rhodin, A.G.J., van Dijk, P.P., Parham, J.F. & Iverson, J.F. 2009. Turtles of the world:
annotated checklist of taxonomy and synonymy, 2009 update, with conservation status
summary. Pp. 39–84 in: Rhodin, A.G.H., Pritchard, P.C.H., Saumure, R.A., Buhlmann,
K.A. & Iverson, J.B. (Eds.), Conservation biology of freshwater turtles and tortoises: a
compilation project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group.
(Chelonian Research Monographs No. 5).
Sauzier, T. 1893. Les tortues de terre gigantesques des Mascareignes et de certaines autres îles
de la Mer des Indes. 32 pp. G. Masson, Paris.
Scarr, D. 2000. Seychelles since 1770. History of a slave and post-slavery society. 232 pp. Hurst
& Co., London.
Stoddart, D.R. 1971. Settlement, development and conservation of Aldabra. Philosophical
Transactions of the Royal Society of London, B 260: 611–628.
Stoddart, D.R. & Peake, J.F. 1979. Historical records of Indian Ocean giant tortoise
populations. Philosophical Transactions of the Royal Society of London, B 286: 147–161.
Toussaint, A. 1967. La routes des îles: contribution à l’histoire maritime des Mascareignes. 540
pp. SEVPEN, Paris.

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