The Chaco tortoise (Chelonoidis chilensis), also known commonly as the Argentine tortoise, the Patagonian tortoise, or the southern wood tortoise, is a
species of
tortoise in the
familyTestudinidae. The species is
endemic to
South America.
Geographic range
The Chaco tortoise is mainly found in
Argentina, but also in
Bolivia and
Paraguay, mainly within the Chaco and Monte ecoregions. Its distribution is mainly limited by temperature-related variables, and precipitation in the reproductive period.[3]
Taxonomy
The
scientific name for this species, Chelonoidis chilensis, is misleading because it is not native to
Chile. It occurs mainly in Argentina, Bolivia and neighboring Paraguay. When the species was first described by
Gray in 1870, he mistakenly thought that
Mendoza was in Chile instead of Argentina (
the city was transfer in 1776), thus the misnomer.
Sclater corrected Gray's mistake in the same year. However, the rules of
nomenclature give precedence to the name chilensis, even though it was based on an erroneous assumption, and the name has persisted.
Description
The
carapace of C. chilensis can measure up to 43.3 cm (but usually less than 25 cm) in a straight line, and may be either totally yellowish brown or have dark-brown to black rings surrounding a tan center on each
scute. Specimens found farther south tend to be much larger than those found in farther north populations. The rim of the shell is slightly serrated and has a dark wedge of pigment at the back edge of each scute. The
plastron may be uniformly yellowish-brown or have a dark triangular wedge along the seams of each scute. The head, limbs and tail are greyish to yellowish-brown, with the front of each forelimb covered with large, angular scales and each thigh featuring several enlarged
tubercles.
Diet
Like all tortoise species, the Chaco tortoise is primarily herbivorous, consuming grasses, shrubs, fruits, and cactus pads.
Species status
There is only one recognized species.[4] However, some researchers believe C. chilensis should be divided into three species: C. chilensis, C. petersi, and C. donosobarrosi. Some support C. donosobarrosi as a subspecies (C. chilensis donosobarrosi). There is research to indicate that it may qualify as a separate species, while C. petersi may just be a variant of C. chilensis, the variances being
clinal variations in adjacent populations.[5] However, these taxa mentioned have all been formally synonymised[4] and accepted.[6] The morphological variation is explainable as a factor of elevation.[6] Historically, these have been viewed as separate taxa, with little work done to confirm or deny it. Subsequent molecular analysis has found little to no genetic variation.[7]
^
abFritz, U.; Alcalde, L.; Ramírez-Vargas, M.; Goode, E.V.; Fabius-Turoblin, D.U.; Praschag, P. (2012a). "Northern genetic richness and southern purity, but just one species in the Chelonoidis chilensis complex". Zoologica Scripta. 41 (3): 220–232.
doi:
10.1111/j.1463-6409.2012.00533.x.
hdl:11336/27111.
S2CID86477800.
^
abRhodin, Anders G.J.; van Dijk, Peter Paul; Iverson, John B.; Shaffer, H. Bradley; Roger, Bour (2012). "Turtles of the world, 2012 update: Annotated checklist of taxonomy, synonymy, distribution and conservation status". Chelonian Research Monographs. 5.
doi:
10.3854/crm.5.000.checklist.v5.2012.
ISBN978-0965354097.
^Turtle Taxonomy Working Group (van Dijk PP, Iverson JB, Rhodin AGJ, Shaffer HB, Bour R). 2014. Turtles of the world, 7th edition: annotated checklist of taxonomy, synonymy, distribution with maps, and conservation status.
^Beolens, Bo;
Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp.
ISBN978-1-4214-0135-5. (Geochelone donosobarrosi, p. 74).
Boulenger GA (1889). Catalogue of the Chelonians, Rhynchocephalians, and Crocodiles in the British Museum (Natural History). New Edition. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). x + 311 pp. + Plates I-III. ("Testudo argentina", p. 159).
Gray JE (1870). "Notice of a new Chilian [sic] Tortoise (Testudo chilensis)". Ann. Mag. Nat. Hist., Fourth Series6: 190. ["Testudo (Gopher) chilensis", new species].