IR Home
AME
Home
Editors
Forthcoming
Information
Subscribe
Journals
Home
MEPS
AME
CR
DAO
ESEP
ESR
Search
Subscribe
Book Series
EE Books
Top Books
ESEP Books
Order
EEIU Brochures
(pdf format)
Discussion Forums
Home
Research
IR Research
Institutions
International Ecology Institute
Eco-Ethics International Union
Foundation
Otto Kinne Foundation
 | |
AME 38:239-247 (2005)
|
Abstract
|
Molecular identity of strains of heterotrophic flagellates isolated from surface waters and deep-sea sediments of the South Atlantic based on SSU rDNA
Frank Scheckenbach1, Claudia Wylezich1, Markus Weitere1, Klaus Hausmann2, Hartmut Arndt1,*
1Department of General Ecology and Limnology, Zoological Institute, University of Cologne, 50923 Cologne, Germany
2Institute of Biology/Zoology, Free University of Berlin, Research Group Protozoology, 14195 Berlin, Germany
*Corresponding author. Email: hartmut.arndt@uni-koeln.de
ABSTRACT: Whereas much is known about the biodiversity of prokaryotes and macroorganisms in the deep sea, knowledge on the biodiversity of protists remains very limited. Molecular studies have changed our view of marine environments and have revealed an
astonishing number of previously unknown eukaryotic organisms. Morphological findings have shown that at least some widely distributed nanoflagellates can also be found in the deep sea. Whether these flagellates have contact with populations from other
habitats is still uncertain. We performed a molecular comparison of strains isolated from deep-sea sediments (>5000 m depth) and surface waters on the basis of their small subunit ribosomal DNA (SSU rDNA). Sequences of Rhynchomonas nasuta,
Amastigomonas debruynei, Ancyromonas sigmoides, Cafeteria roenbergensis and Caecitellus parvulus were analysed, and 2 contrasting results obtained. Firstly, we found nearly identical genotypes within 1 morphospecies (C.
roenbergensis), and secondly, quite different genotypes within certain morphospecies (R. nasuta, A. sigmoides and C. parvulus). In addition, high genetic distances between the different strains of A. sigmoides and C.
parvulus indicate that these morphospecies should be divided into different at least genetically distinguishable species. In contrast, some heterotrophic nanoflagellates must indeed be regarded as being cosmopolitan. According to the low genetic
distances between isolates of R. nasuta, A. debruynei and C. roenbergensis as well as between our isolates of A. sigmoides from deep-sea and surface waters, exchanges between these habitats and also on a global scale might be
possible. In summary, our results show that 3 morphospecies obviously contain several cryptic species, while some of the investigated genotypes occur in both deep-sea as well as in surface waters.
KEY WORDS: Biodiversity · Deep sea · Heterotrophic flagellates · Molecular ecology · Phylogeny · Angola Basin · SSU rDNA
Full text in pdf format
Published in AME Vol.
38, No. 3
(2005) on March 18
Print ISSN: 0948-3055; Online ISSN: 1616-1564.
Copyright © Inter-Research, Oldendorf/Luhe, 2005
|
