A taxonomic revision of geoemydid turtles from Siwalik-age of India and Pakistan
Author
Garbin, Rafaella C.
A8FCEF2B-7524-46C3-808C-D9CBFBC08017
Department of Geosciences, University of Fribourg, Fribourg; Chemin du Musée 6, 1700 Fribourg, Switzerland. & urn: lsid: zoobank. org: author: A 8 FCEF 2 B- 7524 - 46 C 3 - 808 C-D 9 CBFBC 08017 & Corresponding author: garbin. rafaella @ gmail. com
garbin.rafaella@gmail.com
Author
Bandyopadhyay, Saswati
02005D35-6DA9-4A7E-B838-16F4FEF108DA
Geological Studies Unit, Indian Statistical Institute, Kolkata; Barrackpore Trunk Road 233, Kolkata, India. & Email: saswati @ isical. ac. in & urn: lsid: zoobank. org: author: 02005 D 35 - 6 DA 9 - 4 A 7 E-B 838 - 16 F 4 FEF 108 DA
saswati@isical.ac.in
Author
Joyce, Walter G.
C30D317A-0029-439C-8446-31281771ADA5
Department of Geosciences, University of Fribourg, Fribourg; Chemin du Musée 6, 1700 Fribourg, Switzerland. & Email: walter. joyce @ unifr. ch & urn: lsid: zoobank. org: author: C 30 D 317 A- 0029 - 439 C- 8446 - 31281771 ADA 5
walter.joyce@unifr.ch
text
European Journal of Taxonomy
2020
2020-05-26
652
1
67
journal article
21809
10.5852/ejt.2020.652
64fd24bb-ee1d-44d7-ac6a-25e8d5f96777
2118-9773
3860236
DC65C142-53F1-4416-A916-8F78C27DCF93
Genus
Batagur
Gray, 1856
Figs 10–11
Type
species
Batagur baska
(
Gray, 1830
)
.
Differential osteological diagnosis using shell characters
A representative of
Batagur
can be diagnosed by the presence of a large carapace size (median carapace length of more than
40 cm
in adults), a well-developed bridge, well-developed axillary and inguinal buttresses, neural scutes with anterior short sides, a long third neural bone, a short, anteriorly truncated gular scute, an entoplastron that is not intersected by the humeropectoral sulcus and a short anal notch.
Fig. 10.
BMNH 39834, holotype of
Batagur cautleyi
Lydekker 1885
, here identified as
Batagur
sp.
A
. Photograph of carapace.
B
. Illustration of carapace.
C
. Photograph of plastron.
D
. Illustration of plastron. Scale bar: 3 cm.
Fig. 11.
IM E.176, previously undescribed, here identified as
Batagur
sp.
A
. Photograph of carapace.
B
. Illustration of carapace.
C
. Photograph of plastron.
D
. Illustration of plastron. Scale bar: 3 cm.
Material examined
INDIA
•
1 specimen
, holotype of
Batagur cautleyi
Lydekker, 1885
;
Siwalik Hills
; Miocene–Pliocene;
BMNH 39834
.
COUNTRY UNKNOWN •
1 specimen
;
IM E.176
.
Description
BMNH 39834 (
Fig. 10
),
holotype
of
Batagur cautleyi
– This an almost complete shell from the Miocene/ Pliocene of the Siwalik Hills, likely of
India
, showing the majority of sulci and of the sutures along the center of the carapace. It was originally figured by
Lydekker (1885a
: pl. 24.1), but our observations reveal many additional sutures. There are no signs of growth annuli. The specimen likely is an adult female due to its large size (carapace length greater than
54 cm
). A small protuberance on neural IV suggests the previous presence of a median keel. A cervical scute is present. The first vertebral scute is longer than wide and shows a lateral constriction. Neurals II–IV have anteriorly short sides, but neural V has a short left posterior side, which is probably abnormal. The sulcus between the second pleural and the third vertebral is almost straight. The anterior plastral margin is straight and lacks an inflection on the contact of the gularohumeral sulcus. The pectoroabdominal sulcus contacts the sulcus between fifth and sixth marginal scutes. The anal notch is not preserved in this specimen. No plastral sutures can be seen.
IM E.176 (
Fig. 11
) – This is a well-preserved specimen that lacks provenance data and appears to be unpublished. The majority of sutures and sulci are clearly visible. This is an adult specimen due to its large size (carapace length greater than
35 cm
), but its gender is unknown. A median carapacial keel is present on the posterior parts of the carapace and is strongly marked over neurals IV and VI. The carapace is rather domed at its center, with no signs of growth annuli. Vertebral scutes are subrectangular and have equally sized anterior and posterior margins. Neurals II to VI are anteriorly shortsided. Gular scutes appear to be wider than long and overlap part of the entoplastron. The humeropectoral sulcus is located posterior to the entoplastron. The pectoroabdominal sulcus does not intersect the hyohypoplastron suture and has two lateral notches, suggesting the former presence of parasagital plastral keels at the bridge.
Comments
We attributed BMNH 39834 and IM E.176, the
type
series of
Batagur cautleyi
, to
Batagur
indet. based on their massive size, highly domed carapace, and presence of an axillary notch and rather straight anterior plastral margin. However, we cannot identify these specimens to species level even though they display unique character combinations. See Discussion (
Batagur cautleyi
from the Siwalik Hills) for additional details.