FIELD DISTRIBUTION AND SULFIDE TOLERANCE OF CAPITELLA-CAPITATA (ANNELIDA, POLYCHAETA) AROUND SHALLOW WAFER HYDROTHERMAL VENTS OFF MILOS (AEGEAN SEA) - A NEW SIBLING SPECIES

Citation
I. Gamenick et al., FIELD DISTRIBUTION AND SULFIDE TOLERANCE OF CAPITELLA-CAPITATA (ANNELIDA, POLYCHAETA) AROUND SHALLOW WAFER HYDROTHERMAL VENTS OFF MILOS (AEGEAN SEA) - A NEW SIBLING SPECIES, Marine Biology, 130(3), 1998, pp. 447-453
Citations number
36
Categorie Soggetti
Marine & Freshwater Biology
Journal title
ISSN journal
00253162
Volume
130
Issue
3
Year of publication
1998
Pages
447 - 453
Database
ISI
SICI code
0025-3162(1998)130:3<447:FDASTO>2.0.ZU;2-2
Abstract
The cosmopolitan polychaete Capitella capitata, known as a complex of opportunistic sibling species, usually dominates the macrobenthos of p olluted or unpredictable environments. PL population of C. capitata, t ermed Capitella sp. M, was found in a shallow water hydrothermal vent area south of Miles (Greece). Here, this population occurs close to ve nt outlets (termed the ''transition zone''), an environment with steep gradients of temperature, salinity and pH and increased sulphide conc entrations of up to 710 mu M. The field distribution of C. capitata in relation to sulphide concentrations around the vent outlets was inves tigated and sulphide tolerance experiments were conducted on laborator y-cultured worms to elucidate possible adaptations of Capitella sp. M to these extreme environmental conditions. In order to investigate whe ther the population from the Miles hydrothermal vent area can be consi dered a distinct sibling species within the C. capitata complex, cross breeding experiments and analysis of general protein patterns were con ducted with Capitella sp. M and three other C. capitata populations of different ecological ranges. Capitella sp. M showed high resistance ( median survival time: 107 +/- 38 h) to anoxia plus high sulphide conce ntrations of 740 mu M. It seems that the ability to survive high-sulph ide conditions in combination with reduced interspecific competition e nables the polychaete to maintain a continuous population in this rigo rous habitat. From the extremely high tolerance to anoxia and sulphide , shown in both the crossbreeding experiments and the analysis of tota l proteins, it can be concluded that Capitella sp. M from the Miles hy drothermal vent area represents a separate sibling species within the C. capitata complex.