THE LIFE-CYCLE OF ROTALIELLA-ELATIANA N-SP - A TINY MACROALGAVOROUS FORAMINIFER FROM THE GULF OF ELAT

A new foraminiferan species, Rotaliella elatiana n. sp., was isolated in the Gulf of Elat, where it lives in association with a macrophytic green alga, Enteromorpha. The agamont of this tiny new species has a transparent test composed of a bilocular embryonic chamber followed by six to seven trochospirally coiled inflated chambers. The spiral sutures are undulated. The umbilical side has numerous denticules and has radial grooves. The gamont has only one inflated chamber. Rotaliella elatiana has a classical, heterophasic life cycle, with a regular alternation of diploid agamontic phase and haploid gamontic phase. The gamontic phase of the life cycle is exceptionally reduced and the uninucleated gamonts pair immediately after they build their first chamber. A few cases of autogamic reproduction were observed. R. elatiana is a heterocaryotic species; agamonts have one somatic and two to three generative nuclei.