Sunday, June 30, 2019

[Herpetology • 2019] Pseudocalotes austeniana (Annandale, 1908) • Range Extension of the Rare Agamid (Sauria, Draconinae) in the East Himalaya, with Comments on Its Ontogenetic Shift


Pseudocalotes austeniana (Annandale, 1908)

in Wang, Ci, Jiang, et al., 2019.
 Abhor Hills Agama  || DOI: 10.15560/15.3.425

Abstract
Despite its recognition since the early 1900s, the agamid lizard Pseudocalotes austeniana remains known based on 3 vouchered specimens only from the East Himalaya, and little is known about its general biology. During herpetological surveys of Tibet, China, we collected 3 specimens of P. austeniana from Medog County, southeastern Tibet, including the first juvenile specimen ever vouchered. We provide a detailed description based on new material of this enigmatic species, report on a range extension of 400 km northeastward from its type locality, its ontogenetic shift, and clutch size.

Keywords: Agamidae, Himalaya, Mictopholis, Salea, synonym



Figure 2. Adult female Pseudocalotes austeniana (KIZ 013873) in life.
A. Dorsolateral view of body. B. Ventral view of body. C. Lateral, close-up view of head. D. Dorsal, close-up view of body. Photographs by Kai Wang.

Figure 3. Photographed individuals of Pseudocalotes austeniana (not vouchered) in Medog County, Nyinchi Prefecture, Tibet, China. 
A. Dorsal view of an adult female from 62K, Medog. B. Lateral view of the same adult female from 62K, Medog. C. Juvenile from Hanmi, Medog. 
Photographs by Chao Wu and Zheng Shi.

Figure 5. Eggs of Pseudocalotes austeniana (produced by the vouchered female TMNH 20170001). 
Photograph by Shiyang Weng.

    

 Pseudocalotes austeniana (Annandale, 1908)
 Salea austeniana 

Identification. The recently collected adult and juvenile specimens from Tibet resemble closely the pholidosis characteristics of the vouchered holotype and topotypic specimen of Pseudocalotes austeniana (Table 1). In summary, these specimens are identified as P. austeniana based on the following morphological characters (following Mahony 2010): (1) tympanum exposed; (2) sub-ocular scale row singular, or multiple but one distinctively enlarged; (3) head robust, HW/HL > 59.7%, HD/HW > 72%, HD/HL > 43%; (4) distinct, strongly-developed cranial ridges present on dorsal and lateral surfaces of occipital region of head, forming rectangular, convex areas on temporal region of head and triangular concave area on posterior lateral region of head; (6) postorbital and postoccipital spines absent; (7) nuchal crest in triangular shape or short lanceolate shape, not strongly differentiated from dorsal crests; (8) mid-dorsal scale count less than 39; (9) longitudinal gular fold present, highly developed in dewlap, with a distinct, pointy tip toward posterior end; (10) transverse gular fold absent; (11) dorsal scales heterogeneous in size and shape, flat, feebly keeled or smooth, arranged irregularly in most parts, some enlarged ones in approximate transverse rows; (12) enlarged scales of dorsum not arranged into clear dorsolateral or V-shaped rows; (13) ventral body scales smooth or feebly keeled, larger than background dorsal scales, distinctively heterogeneous in size and shape, irregularly arranged; (14) antehumeral fold present; and (15) axillary fold present.
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Figure 3. Photographed individuals of Pseudocalotes austeniana (not vouchered) in Medog County, Nyinchi Prefecture, Tibet, China.
A. Dorsal view of an adult female from 62K, Medog. B. Lateral view of the same adult female from 62K, Medog. C. Juvenile from Hanmi, Medog. Photographs by Chao Wu and Zheng Shi.



Distribution range. Prior to our observations of Pseudocalotes austeniana in the field, the species was thought to be a rare endemic to the southern parts of Southern Tibet (Mahony 2010, Venugopal 2010, 2013), and the species was not officially listed as a member of the Chinese herpetofauna (Zhao and Jiang 1977, Zhao and Adler 1993, Zhao et al. 1999, Cai et al. 2015). However, the newly discovered populations represent a range expansion of about 400 km northeastward from the species’ previous range limits in the East Himalaya. Given the recognized habitat connectivity and similar environment spanning this region, it is likely that P. austeniana is currently, or once was, distributed continuously across this area. Future survey efforts for this species should focus on habitat to the west in Bhutan. Additional studies of this enigmatic and secretive lizard are needed to better understand its ecology, population densities, and full geographic distribution.


 Kai Wang, Ping Ci, Ke Jiang, Shiyang Weng, Cameron D. Siler and Jing Che. 2019. Range Extension of the Rare Agamid, Pseudocalotes austeniana (Annandale, 1908) (Reptilia, Sauria, Draconinae) in the East Himalaya, with Comments on Its Ontogenetic Shift. Check List. 15(3); 425-433.  DOI: 10.15560/15.3.425

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