Epiphytic seaweeds and invertebrates associated with South African populations of the rocky shore seagrass Thalassodendron leptocaule — a hidden wealth of biodiversity

  • CM Browne
  • R Milne
  • C Griffiths
  • JJ Bolton
  • RJ Anderson

Abstract

Seagrasses support a great diversity of epiphytic organisms. There are no detailed published accounts of algae and animals growing on seagrasses in South Africa. The seagrass Thalassodendron leptocaule  (previously known Thalassodendron ciliatum) is unique among southern African seagrasses in that it occurs on exposed rocky outcrops along the Mozambican and north-eastern South African coasts; most other seagrasses are restricted to sheltered bays and estuaries. Here we present accounts of species of flora and fauna identified growing epiphytically on this seagrass in northern KwaZulu-Natal. A total of 52 taxa of macroalgae and 204 species of macroinvertebrates were identified as epiphytic on South African T. leptocaule. The most frequently observed macroalgal epiphytes were predominantly Rhodophyta and were common among periodically exposed, intertidal and subtidal habitats. The crustose red coralline algae Pneophyllum amplexifrons and Hydrolithon farinosum were frequently observed, primarily on stems and leaves of the seagrass respectively. The most diverse groups of epiphytic invertebrates were Arthropoda, Annelida and Mollusca, which together comprised 76% of the macroinvertebrate species recorded. This seagrass species is evidently an important substratum and ecosystem that supports a hidden wealth of biodiversity.

Keywords: biodiversity, intertidal, macroinvertebrates, seaweeds, Sodwana Bay, species richness

African Journal of Marine Science 2013, 35(4): 523–531

Author Biographies

CM Browne
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag, Rondebosch, South Africa
R Milne
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag, Rondebosch, South Africa
C Griffiths
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag, Rondebosch, South Africa
JJ Bolton
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag, Rondebosch, South Africa
RJ Anderson
Department of Biological Sciences and Marine Research Institute, University of Cape Town, Private Bag, Rondebosch, Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, Private Bag X2, Rogge Bay 8012, South Africa
Published
2013-12-19
Section
Articles

Journal Identifiers


eISSN: 1814-2338
print ISSN: 1814-232X