TY - JOUR
T1 - Molecular and morphological assessment of Australia's most endangered snake, Hoplocephalus bungaroides, reveals two evolutionarily significant units for conservation
AU - Sumner, Joanna
AU - Webb, Jonathan K.
AU - Shine, Richard
AU - Keogh, J. Scott
PY - 2010/6
Y1 - 2010/6
N2 - The Broad-headed snake Hoplocephalus bungaroides is one of Australia's most endangered vertebrates. Extant populations of H. bungaroides are restricted to several geographically isolated reserves to the north, west, and south of Sydney. We analysed mitochondrial DNA from 184 specimens drawn from across the geographic range of the Broad-headed snake. Phylogenetic analysis demonstrated that H. bungaroides comprises two divergent mitochondrial lineages with a "northern" clade comprising populations west and north of Sydney and a "southern" clade comprising animals in Morton National Park. The two clades differ by an uncorrected genetic distance of 1. 7%, which implies a divergence dating to approximately 755,000-850,000 years ago. We complemented our molecular data set with a detailed analysis of morphological variation both between and within the genetic clades. The two H. bungaroides genetic clades are morphologically indistinguishable and show little sexual dimorphism. Our results demonstrate that the populations north and south of this biogeographic split function as two distinct populations with no recent gene flow. There is no reason for separate taxonomic recognition of these two clades, but they do represent distinct evolutionarily significant units (ESUs) that require separate conservation management. In addition, within the northern ESU, populations from Royal National Park, Blue Mountains National Park, Wollemi National Park, and the Sydney Water Catchment supply areas should be considered as separate management units to conserve both evolutionary and ecological processes.
AB - The Broad-headed snake Hoplocephalus bungaroides is one of Australia's most endangered vertebrates. Extant populations of H. bungaroides are restricted to several geographically isolated reserves to the north, west, and south of Sydney. We analysed mitochondrial DNA from 184 specimens drawn from across the geographic range of the Broad-headed snake. Phylogenetic analysis demonstrated that H. bungaroides comprises two divergent mitochondrial lineages with a "northern" clade comprising populations west and north of Sydney and a "southern" clade comprising animals in Morton National Park. The two clades differ by an uncorrected genetic distance of 1. 7%, which implies a divergence dating to approximately 755,000-850,000 years ago. We complemented our molecular data set with a detailed analysis of morphological variation both between and within the genetic clades. The two H. bungaroides genetic clades are morphologically indistinguishable and show little sexual dimorphism. Our results demonstrate that the populations north and south of this biogeographic split function as two distinct populations with no recent gene flow. There is no reason for separate taxonomic recognition of these two clades, but they do represent distinct evolutionarily significant units (ESUs) that require separate conservation management. In addition, within the northern ESU, populations from Royal National Park, Blue Mountains National Park, Wollemi National Park, and the Sydney Water Catchment supply areas should be considered as separate management units to conserve both evolutionary and ecological processes.
KW - Hoplocephalus bungaroides
KW - phylogeography
KW - evolutionarily significant units
KW - conservation
KW - morphology
UR - http://www.scopus.com/inward/record.url?scp=77952882691&partnerID=8YFLogxK
U2 - 10.1007/s10592-009-9863-7
DO - 10.1007/s10592-009-9863-7
M3 - Article
AN - SCOPUS:77952882691
SN - 1566-0621
VL - 11
SP - 747
EP - 758
JO - Conservation Genetics
JF - Conservation Genetics
IS - 3
ER -