Dasia johnsinghi Harikrishnan, Vasudevan
Creators: name: Chandramouli, S. R.
name: Thasun Amarasinghe, A. A.
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Reptilia
Squamata
Scincidae
Dasia
Dasia johnsinghi

description: Dasia johnsinghi Harikrishnan, Vasudevan, de Silva, Deepak, Kar, Naniwadekar, Lalremruata, Prasoona &
Aggarwal, 2012
Dasia johnsinghi Harikrishnan, Vasudevan, de Silva, Deepak, Kar, Naniwadekar, Lalremruata, Prasoona & Aggarwal,
2012
Dasia haliana (non Euprepes halianus Nevill, 1887)— Vickram & Johnsingh 1985 part
Dasia haliana —Joshua & Sekar 1985 part; Karthikeyan 1991 part, Somaweera & Somaweera 2009 part
Dasia subcaeruleum (non Lygosoma subcaeruleum Boulenger 1891)— Wickramasinghe et al. 2011 part
(6) Harikrishnan et al. (2012:45) redescribed Dasia subcaerulea on the basis of a single specimen registered as ZSIC25945, collected by M.S. Chaitra from Singsar game road, Kudremukh National Park, which is> 500 km north of the type locality of D. subcaerulea. However, they erroneously mention the registration number of this specimen to be BNHS 363 in their appendix of specimens examined. As the authors were unable to examine the holotype of Dasia subcaerulea, they obtained photographs and data from the Natural History Museum, London, where it is housed. They state to have assigned their new specimen from Kudremukh to D. subcaerulea based “only on external morphological characters”. The photographs of the holotype in Harikrishnan et al. (2012: 46) (and in Wickramasinghe et al., 2011: 1967) clearly depict the prefrontals being in broad contact with each other, completely preventing contact between the frontal and fronto-nasal. In the specimen of D. subcaerulea from Kudremukh (ZSIC 25945) the prefrontals areseparated from each other, enabling contact between the frontal and fronto-nasal, as stated by the authors themselves (Harikrishnan et al. 2012: 45). In addition, there are differences in the number of midbody scale rows [28 as recorded by Smith (1949) vs. 26 in Harikrishnan et al. (2012)]. This is especially ironic considering that the authors themselves have used prefrontal midline contact and midbody scale rows as diagnostic characters in their own key to distinguish species of Dasia, and have also genetically tested distributional outliers (see D. olivacea vs. D. cf. olivacea). While it is known that Dasia species are rare to encounter in south India (personal observations), the mismatch of these significant and diagnostic morphological characters coupled with the very distant and ecologically heterogeneous collection localities (Bodinayakanur: 10.02° N, 77.35° E, 353 m asl. vs. Kudremukh: 13.21° N, 75.18° E, 750 m asl.), across a significant bio-geographic barrier, the Palghat gap, raise serious doubt on the veracity of their allocation of ZSIC 25945 to D. subcaerulea sensu Smith (1949). This allocation impacts the concept of D. subcaerulea, and hence the phylogeographic implications presented by the authors. As ZSIC 25945 is currently an outlier to D. subcaerulea sensu Smith (1949), both morphologically and geographically, it would be important to seek topotypic specimens of D. subcaerulea and of populations from between the type locality and Kudremukh.
Moreover, the number of congeners in the genus Dasia was repeatedly misinterpreted by Harikrishnan et al. (2012). In the first line of their introduction they mentioned “The genus is presently composed of seven valid species ...”, but the map placed right below the above statement shows eight valid species (even excluding Dasia cf. olivacea and their new species D. johnsinghi which was described in that paper). Again in their discussion they misinterpreted the number of congeners in Dasia as “The description of D. johnsinghi sp. nov. from the southern Western Ghats brings the total number of Dasia species to eight ...” (see Harikrishnan et al. 2012: 48)”. All of the above statements are erroneous, bringing the total species to nine including their new species, D. johnsinghi.
We emphasize the importance of inferences made in taxonomic papers, which will be applied by other “end-users” such as ecologists and conservation managers. Hence, a more cautious approach towards sensitive taxonomic and nomenclatural issues is needed. Ironically, the errors that we have highlighted here recall the concerned criticism raised by Vasudevan et al. (2007) for taxonomic papers being “pernicious” by publishing “inaccurate and imprecise” descriptions that will hinder the progress in taxonomy. Such mistakes have unwittingly appeared in a number of recent research publications, and several examples in this region have been highlighted recently (Pethiyagoda, 2007). We recommend a cautious approach towards sensitive taxonomic issues and insist that taxonomic papers should undergo a thorough peer review by practicing taxonomists (Alberts et al. 2008; Bahir 2009; Bahir & Gabadage 2009), thereby minimizing the possibilities for such mistakes in future.
description: Published as part of Chandramouli, S. R. & Thasun Amarasinghe, A. A., 2015, On some recent taxonomic advancement and the resultant problems in the arboreal skink genus Dasia Gray, 1839 (Reptilia: Scincidae), pp. 495-500 in Zootaxa 3914 (4) on pages 497-498, DOI: 10.11646/zootaxa.3914.4.9, http://zenodo.org/record/233362