eCite Digital Repository

Genetic differentiation in the circum - Antarctic sea spider Nymphon australe (Pycnogonida; Nymphonidae)


Arango, CP and Soler-Membrives, A and Miller, KJ, Genetic differentiation in the circum - Antarctic sea spider Nymphon australe (Pycnogonida; Nymphonidae), Deep Sea Research Part II: Topical Studies in Oceanography, 58, (1-2) pp. 212-219. ISSN 0967-0645 (2011) [Refereed Article]

Not available

Copyright Statement

The definitive version is available at

Official URL:

DOI: doi:10.1016/j.dsr2.2010.05.019


Nymphon australe Hodgson 1902 is the most abundant species of sea spiders in the Southern Ocean. The species is recognised as highly morphologically variable, circumpolar and eurybathic—which is surprising given that sea spiders lack a planktonic stage; the fertilised eggs and larvae remain attached to the ovigers of the father, and consequently have limited dispersal capacity. In this study, we investigate the genetic structure of N. australe populations around Antarctica, confronting the apparent limited dispersal ability with its recognised circumpolarity. Here we analyse mitochondrial DNA of specimens from Antarctic Peninsula, Weddell Sea and East Antarctica to determine if they represent populations of the widespread N. australe — or instead we can recognise cryptic species – and how genetically different they are. Both CO1 and 16S sequence data produced single haplotype networks for N. australe from all three Antarctic locations without indication of cryptic speciation. However, we found strong phylogeographic structure among the three Antarctic locations based on CO1 data. There was only a single shared haplotype between the Antarctic Peninsula and the East Antarctica locations, and all three regions were significantly subdivided from each other (FST=0.28, p<0.01). Furthermore, within the Antarctic Peninsula and East Antarctic locations, we found evidence of genetic subdivision between populations of N. australe separated by 10–100 s of km (FST=0.07–0.22, p<0.05), consistent with sea spiders life history traits indicating a limited dispersal capability. We conclude N. australe represents a single circum-Antarctic species that, despite its limited dispersal abilities, has successfully colonised large parts of the Antarctic marine ecosystem through geological history. However, clear genetic differences among and within locations indicate contemporary gene flow is limited, and that populations of N. australe around Antarctica are effectively isolated.

Item Details

Item Type:Refereed Article
Keywords:Pycnogonida, Nymphonidae, Genetic diversity, Dispersal, Mitochondrial DNA, Phylogeography, Southern ocean, Antarctica, Weddell sea, East Antarctica
Research Division:Biological Sciences
Research Group:Evolutionary biology
Research Field:Biogeography and phylogeography
Objective Division:Environmental Management
Objective Group:Management of Antarctic and Southern Ocean environments
Objective Field:Biodiversity in Antarctic and Southern Ocean environments
UTAS Author:Miller, KJ (Dr Karen Miller)
ID Code:66143
Year Published:2011
Web of Science® Times Cited:65
Deposited By:IMAS Research and Education Centre
Deposited On:2011-01-05
Last Modified:2012-04-11
Downloads:5 View Download Statistics

Repository Staff Only: item control page