Respiratory adaptations in the scaleworms of the genus Branchipolynoe, polynoid polychaetes commensal of deep-sea mussels
Hourdez, S.; Lallier, F.; Jouin-Toulmond, C.; Green, B.; Weber, R.E.; Toulmond, A. (1997). Respiratory adaptations in the scaleworms of the genus Branchipolynoe, polynoid polychaetes commensal of deep-sea mussels, in: Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2): pp. 125 In: (1997). Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2)[s.n.][s.l.]. 111-149 pp., more In: Cahiers de Biologie Marine. Station Biologique de Roscoff: Paris. ISSN 0007-9723; e-ISSN 2262-3094, more |  |
| Authors | | Top | - Hourdez, S.
- Lallier, F.
- Jouin-Toulmond, C.
| - Green, B.
- Weber, R.E.
- Toulmond, A., more
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| Abstract | A commensal scale-worm of the genus Branchipolynoe is often found inside mussels clustered around deep-sea hydrothermal vents and cold seeps (Pettibone, 1984; Pettibone, 1986; Miura & Hashimoto, 1991). In addition to the constraints of the hydrothermal environment, such as rapid and large variations of temperature, pH, oxygen, sulphide, and carbon dioxide concentrations, living in the pallial cavity of a mussel may obviously affect respiration. The aim of this study was to explore anatomical and physiological respiratory adaptations in Branchipolynoe seepensis, an Atlantic species compared to B. symmytilida, an East-Pacific species. In contrast to littoral species belonging to the family Polynoidae, Branchipolynoe species possess two evident specificities: numerous gills, and abundant haemoglobin. Anatomical studies have shown that the gills have a high specific surface area, and present a reduced diffusion distance. The hollow gills are not vascularized but their coelom is connected to the large body cavity which contains a dissolved extracellular haemoglobin. The reduced vascular system also contains an extracellular haemoglobin. In B. symmytilida, gel chromatography revealed that, besides a small amount of a 3.5.10 super(6) Da Hb typical of annelid hexagonal bilayer Hb (Lamy et al., 1996) and most probably of a vascular origin, two different major Hbs, Cl and C2, coexist in the coelomic fluid. |
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