12. Jahrestagung der Deutschen Gesellschaft für Tropenökologie - gtö. Ulm, 17 - 19.02.1999: Poster P-4.20

Jörg Wiedenmann, Werner Funke
Abteilung Ökologie und Morphologie der Tiere, Universität Ulm, D-89069 Ulm, Germany

The opelet, Anemonia sp. (sulcata) occurs frequently on rocky shores of the Atlantic and the Mediterranean Sea. The animals harbour zooxanthellae within their endoderm. Because of this association the animals can only be found in well illuminated habitats (SCHMIDT 1972). A variety of colour morphs have been described in the last century (GOSSE 1860; ANDRES,1881,1883). These differentiating views are scarcely considered in literature because it is believed that the variability of colours was only caused by the content of zooxanthellae (FECHTER & al. 1985; GÖTHEL 1992; MOOSLEITNER & PATZNER 1995; VALENTIN, 1986).

Our study shows for the first time that the colour of tentacles is produced by a different kind of pigments apart from the colouring of zooxanthellae: two green-fluorescent pigments (GP499; GP522), one orange-fluorescent pigment (OP) and a non-fluorescent red pigment (RP) all located in the ectoderm. The pigments show characteristic spectra and occur in a definite way among the colour morphs. Consequently, with the exception of var. smaragdina II, all morphs which possess at least one of the ectodermal pigments (var. vulgaris, var. smaragdina I, var. viridis, var. rufescens) are most widely spread in lower depths than var. rustica which has none of these pigments. The different depth dispersions of the morphs and the absorption properties of the ectodermal pigments point to a protective function of these pigments from bright sunlight, particularly from UV-radiation.

As fluorescent colour morphs of many coral species are reported in literature, our results may contribute to improve the understanding of reef communities as well.