Rotifers community structure and abundance along Shatt al-Arab River from Garmmat Ali to al-Fao, Southern Iraq

الملخص EN

The Rotifers community along Shatt Al-Arab River was investigated during four seasons of 2006.

49 species belonging to 27 genera recorded.

The genus Brachiouns the highest number of species (7) following by Monostyla and Trichocerca 4 each constituted and Keratella (3) species..

In general Brachionus calyciflorus and Keraktella valga were most frequent and dominant species.

Within the five investigated sites, Al- Karoon station was characterized by highest rotifers density (369 ind.

/ l) and Abu Al-Khaseeb station showed the less density (230 ind.

/ l ).

However, summer was the period of highest densities.

Diversity Indices for the five studied stations were calculated, the value ranged between 1.43–1.61 for Shannon-Weaver index, 6.29-8.47 for richness index, and between 0.51-0.55 for uniformity index.