Mitochondrial DNA analyses of the saltwater crocodile (Crocodylus porosus) from the Northern Territory of Australia
Naomi L. Luck A D , Kristen C. Thomas A D , Victoria E. Morin-Adeline A D , Sophie Barwick A D , Amanda Y. Chong A D , Eliza L. Carpenter A D , LinXiao Wan A D , Cali E. Willet A D , Shannan M. Langford-Salisbury A D , Mary Abdelsayd A D , Rachel A. Ang A D , Sarah J. Atkinson A D , Fabian G. Barcelo A D , Melanie E. Booth A D , Emma J. Bradbury A D , Thomas L. Branighan A D , Jennifer Brown A D , Lesley E. Castillo A D , Nichola D. Chandler A D , Josephine Y. Chong A D , Kimberly J. Collits A D , Emma Cook A D , Rachel E. Cruz A D , Claire A. Farrugia A D , Jessica L. Fletcher A D , Sophie Fletcher A D , Nicole S. Gamaliel A D , Jessica F. Gurr A D , Nathan J. Hallett A D , Grace Hargreaves A D , Teresa Harris A D , Samantha Hollings A D , Ryan L. Hopcroft A D , Danielle Johinke A D , Pippa L. Kern A D , Jane L. Kiddell A D , Kristen E. Kilby A D , Borjana Kragic A D , Jacqueline H. Kwan A D , Joseph I. Lee A D , Jennifer M. Liang A D , Mette C. Lillie A D , Belle C. Lui A D , Sharon W. Luk A D , Kwok H. Lun A D , Kate L. Marshall A D , Jolanta A. Marzec A D , Kellie T. Masters A D , Laura J. Mazurkijevic A D , Jeremy Medlock A D , Christopher Meoli A D , Katrina M. Morris A D , Yvonne H. Noh A D , Hana Okazaki A D , Tamara J. Orourke A D , Elyssa M. Payne A D , Dean J. Powell A D , Antonia R. Quinlivan A D , Thomas J. Reeves A D , Kate Robson A D , Kate L. Robson A D , Leah J. Royle A D , Ryan Stevenson A D , Teigan Sellens A D , ZiChen Sun A D , Amanda L. Sutton A D , Amelia Swan A D , Jason M. Tang A D , Jarrod E. Tinker A D , Suzanne C. Tomlinson A D , Tessa Wilkin A D , Amanda L. Wright A D , Sam T. Xiao A D , Jessica Yang A D , Christine Yee A D , Weerachai Jaratlerdsiri A , Sally R. Isberg A B , Lee Miles A , Damien Higgins A , Amanda Lane A and Jaime Gongora A C
+ Author Affiliations
- Author Affiliations
A Faculty of Veterinary Science, RMC Gunn Building, University of Sydney, Sydney, NSW 2006, Australia.
B Porosus Pty Ltd, PO Box 86, Palmerston, NT 0831, Australia.
C Corresponding author. Email: jaime.gongora@sydney.edu.au
D Undergraduate students, Bachelor of Animal and Veterinary Bioscience program, Faculty of Veterinary Science, University of Sydney. These authors undertook this research during practical classes for a subject in their degree.
Australian Journal of Zoology 60(1) 18-25 https://doi.org/10.1071/ZO12008
Submitted: 17 January 2012 Accepted: 31 May 2012 Published: 9 July 2012
Abstract
The saltwater crocodile is distributed throughout south-east Asia and Australia. In Australia, it is most abundant in the Northern Territory and Queensland, where it is sustainably farmed for its skins and meat. The aim of this study was to elucidate the relationships and genetic structure among saltwater crocodiles from the Northern Territory of Australia using mitochondrial control region sequences from 61 individuals, representing nine river basins and six of unknown origin, as well as published sequences from other regions. Eight mitochondrial control region haplotypes were identified among both published and novel sequences. Three of the haplotypes appear to be restricted to specimens from northern Australia, with a single haplotype being the most widely dispersed across all river basins. Although Analysis of Molecular Variance provides some support for differentiation among river basins, the frequency of shared haplotypes among these geographical units and median-joining network analysis do not support a clear genetic structure or phylogeographic pattern for saltwater crocodiles in the Northern Territory. The results of this study will assist in furthering our understanding of the genetic diversity of wild saltwater crocodile populations used for ranching in the Northern Territory, as well as providing a framework for assessing the origin of unknown specimens in the future.
Additional keywords: mtDNA, control region.
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