The identity of Chelodina oblonga Gray 1841 (Testudines: Chelidae) reassessed
Author
Shea, Glenn
Sydney School of Veterinary Science, B 01, University of Sydney, NSW 2006 Australia & Australian Museum Research Institute, Australian Museum, 1 William St, Sydney, NSW 2010, Australia
Author
Thomson, Scott
Chelonian Research Institute, 402 South Central Avenue, Oviedo, 32765, Florida, USA
Author
Georges, Arthur
Institute for Applied Ecology, University of Canberra, ACT 2601 Australia
text
Zootaxa
2020
2020-05-20
4779
3
419
437
journal article
21355
10.11646/zootaxa.4779.3.9
e39a9333-f0b8-4b2d-b0b1-ff53ae849ae0
1175-5326
3974820
A3CE4100-EDB7-465D-BDCF-1DFAC31EEA3D
3.2.3. Subgenus:
Chelodina
(
Chelydera
)
subgen. nov.
Thomson and Georges, this study.
Type
Species:
Chelodina parkeri
Rhodin & Mittermeier 1976
.
Diagnosis: Large riverine turtles; carapace broadly oval with noticeable flaring about marginal scutes 8–10; plastron narrow, covering only about half of the anterior orifice of the shell in ventral view; plastron of moderate length, approximately twice as long as its width measured anterior to the bridge; head and neck longer than carapace; intergular scute rhomboid in shape with width approximately equal to length. Neck dorsum finely reticulated, lacking obvious tubercles. Osteologically, atlas (C1) elongated; cervical vertebrae 2–4 greatly elongated (centrum about three times as long as wide); transverse processes of cervical vertebrae thickened, not bladelike as in subgenera
Chelodina
and
Macrochelodina
. Skull dorsoventrally flattened, in some species also laterally expanded, resulting in antero-posterior enlargement of palatines. Hyolaryngeal assemblage highly modified; extreme elongation of corpus hyoideum along sulcus tracheae; anterior cornubranchiale expanded, elongated, extending beyond posterior cornubranchiale; epibranchials fully ossified in adults, cartilaginous throughout life in species of the other subgenera. Anterior bridge struts enlarged; suture with pleural 1 extends half-way across pleural; proximal suture of strut enlarged and also contacts 2
nd
pleural in very large specimens; posterior bridge strut enlarged and thickened, but does not contact pleurals; ilium sutures with 8
th
pleural and pygal and is latero-posteriorly rotated. Exposed neural bones usually absent (except for
Chelodina burrungandjii
,
typically with 3–6 exposed neurals;
Smales 2019
). Fluid from ducts in the inguinal and axillary pockets with noticeable odour, but not pungent.
Etymology: The name
Chelydera
is a combination of the Greek χέλυς/χέλυδρος (chelys/chelydros), meaning both a turtle (cf. the similarly snake-necked turtle genus
Chelus
Duméril 1806
) and a water snake, and δειρή (deire), the neck (f.) (
Liddell & Scott 1897
;
Brown 1956
). This is in reference to the common name for this group, the snakenecked turtles. We use a feminine name for the subgenus to agree with
Chelodina
, to avoid a change in gender of any adjectival specific epithets if
Chelydera
is treated as generically distinct by some authors.
FIGURE 4.
Ventral, right lateral and dorsal views of the shell of the paralectotype of
Chelodina oblonga
Gray
(OUMNH 02584). (Images courtesy of K. Child, OUMNH).
Assigned Species:
C. parkeri
Rhodin & Mittermeier 1976
;
C. burrungandjii
Thomson, Kennett & Georges 2000
;
C. expansa
Gray 1857
;
C. kuchlingi
Cann 1997
;
C. rugosa
Ogilby 1890
; †
C. insculpta
De Vis 1897
; †
C. alanrixi
Lapparent de Broin & Molnar 2001
. Vernacular name: Australasian snake-necked turtles