Forthcoming

Nuchal scalation patterns in Iranian Mugger crocodiles (Crocodylus palustris Lesson, 1831) point to an overlooked conservation unit

Authors

  • Malihe Erfani Department of Environmental Sciences, Faculty of Natural Resources, University of Zabol, Zabol, Iran
  • Elham Abtin Department of Environment, Sistan and Baluchestan province, Zahedan, Iran
  • Asghar Mobaraki Wildlife expert, Wildlife Conservation and Management Bureau, Natural Environment Deputy, Department of Environment, Tehran, Iran
  • Haji Gholi Kami Department of Biology, Faculty of Sciences, Golestan University, Gorgan, Iran
  • Dax Pandi Director, Mahim Pandhi Wildlife Foundation, Bhuj, India
  • Colin Stevenson Crocodile of the World, Burford Road, Brize Norton, Oxfordshire, OX18 3NX, United Kingdom
  • Thomas Ziegler Institute of Zoology, University of Cologne, Zülpicher Strasse 47b, D-50674 Cologne, Germany. AG Zoologischer Garten Köln, Riehler Strasse 173, D-50735 Cologne, Germany
  • Dennis Rödder University of Bonn, Curator at LIB, Museum Koenig, Bonn, Germany
  • Anslem De Silva Retired lecturer and consultant herpetologist, Rajarata University, Mihintale, Sri Lanka
  • Nikhil Whitaker Madras Crocodile Bank Trust/Centre for Herpetology, P.O. Box 4, Mamallapuram, Tamil Nadu -603104, India
  • Minh D. Le Central Institute for Natural Resources and Environmental Studies (CRES) & Faculty of Environmental Sciences,Vietnam National University (VNU), Hanoi 19 Le Thanh Tong Street, Hanoi, Vietnam
  • Dinal Samarasinghe Environmental Foundation (Guaranteed) Limited, No. 171, Sri Gnanendra Mawatha, Nawala, Sri Lanka
  • Anirudh Vasava Research Coordinator, Voluntary Nature Conservancy, 101, Radha Darshan, Behind Union Bank of India, Vallabh Vidyanagar- 388120, Gujarat, India
  • Suranjan Karunarathna .M.S. Suranjan Karunarathna, Nature Explorations & Education Team, No. B-1/G-6, De Soysapura Housing Scheme, Moratuwa 10400, Sri Lanka

Keywords:

Conservation unit, Identification guide, Morphological diversity, Mugger crocodiles, Nuchal scutes

Abstract

Nuchal scutes patterns in crocodilians are important for distinguishing species and populations, particularly isolated ones. The study focuses on nuchal scutes numbers and patterns of Mugger Crocodile (Crocodylus palustris (Lesson, 1831)) across its distribution in Iran, India, and Sri Lanka. Data was collected from 146 crocodile photos, analyzing both the numbers and pattern of nuchal scutes. Nonparametric methods were employed due to non-normal data distribution. The Binomial Test indicated no bias from the six-scute pattern, with 50% of Iranian crocodiles having variations from six scutes. Confidence intervals for scutes patterns were 0.41-0.59 in Iran and 0.01-0.13 in India and Sri Lankan crocodiles conformed to the six-scutes pattern. A total of 18 different scute patterns were identified, with unique patterns observed in Iranian crocodiles. The Kruskal-Wallis test revealed significant differences in scute patterns across all data and specifically in Iran. The Mann-Whitney U test indicated differences between the typical scute pattern and others, except for a few specific patterns. Iran exhibited the highest variation in nuchal scute patterns, with diversity increasing towards the north and west. Iranian mugger crocodile populations face threats from flooding, drought, and climate change, necessitating further studies for conservation planning. Also, there is concern about potential genetic bottlenecks due to isolation, highlighting the need for genetic investigation and its possible relationship with morphological diversity.

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Published

2025-11-12

How to Cite

Erfani, M., Abtin, E., Mobaraki, A., Kami, H. G. ., Pandi, D., Stevenson, C., Ziegler, T., Rödder, D., De Silva, A., Whitaker, N., Le, M. D. ., Samarasinghe, D., Vasava, A., & Karunarathna, S. (2025). Nuchal scalation patterns in Iranian Mugger crocodiles (Crocodylus palustris Lesson, 1831) point to an overlooked conservation unit. Journal of Wildlife and Biodiversity, 9(X). Retrieved from https://wildlife-biodiversity.com/index.php/jwb/article/view/1012

Issue

Vol. 9 No. X (2025): Articles in Press

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Original Article

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