Taxonomy and Biogeography of the Polychaetes of the Falkland Islands

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  • Teresa Darbyshire

    Research areas

  • PhD, School of Ocean Sciences, taxonomy, Polychaeta

Abstract

Taxonomic works relating to polychaetes from the Falkland Islands are few and little has been published specifically on them since the early to mid twentieth century. Unusually, the intertidal region has received less attention than subtidal sites with most information coming from Antarctic expeditions that used the Islands as a staging post on their journeys south. Works relating to the wider Magellan region, as well as the Antarctic, are far more numerous. The project detailed by this thesis was conceived to address this dearth of knowledge, put the information gleaned into context with the biogeographical region within which the Falkland Islands sit and to determine whether species distribution around the Islands is affected by the differing current regimes that influence the surrounding waters. In total, 218 taxa are reported, 52 of which have been named so far, including four new species whose published descriptions form part of this document. Over 85% of the named species are already known from the wider Magellan region and significant overlap with South Georgian and Antarctic faunas is also apparent. Cluster analyses and multi-dimensional scaling plots show depth (intertidal versus subtidal) to be the strongest influence on species composition with shore height and sediment type having limited effect and geographic location none. Taxonomic distinctness indices are used to assess the species lists and compare sample sites. Much of the diversity appears to centre on microhabitats such as epifaunal and algal turfs and biogenic encrustations. Syllidae are the most diverse family and dominate some samples, particularly those from epifaunal turf and sieved sediments. Other families appear to use microhabitats, such as epifaunal turf and biogenic encrustations, as nursery areas, with large numbers of juveniles in some samples. Comparisons are made with other intertidal diversity studies from the Scotia Arc and Antarctic.

Details

Original languageEnglish
Awarding Institution
Supervisors/Advisors
Thesis sponsors
  • Amgueddfa Cymru - National Museum of Wales, Cardiff
  • Shakleton Scholarship Fund
Award date29 Oct 2018