Meiobenthic Aquatic Annelids Community in River Tigris Baghdad province / Iraq


A number of 3649 individuals of meiobenthic aquatic annelids worms were sorted from 40 samples of the aquatic plant Ceratophyllm demersum L. collected monthly from four different sites across River Tigris in Baghdad province during a period from February /2017 until December /2017. The sorted worms were identified to 16 species, 10 of them represented Subfamily Naidinae (58%), including Chaetogaster diastrophus, Paranais litoralis, Stylaria lacustris, S. fossularis, Ophidonais serpentina, , Nais simplex, Nais variabilis, Allonais inaequalis, , Dero (Dero) digitata, Dero (Aulophorus) furcata, Slavina appendiculata and Stephensoniana trivandrana . Two species of pristininae Pristina longiseta, and P. aequiseta, also identified and recorded a percentage of 6%, in addition to two species of family Aeolosomatidae, Aeolosoma variegatum, and A.hemprichi with a percentage of 36%. The result revealed that Aeolosoma variegatum was the most abundant species and recorded 1209 individuals with a percentage of 33.13%, followed by Stylaria lacustris and Cheatogaster diastrophus , which they recorded a total individuals number of 621 and 569 with a percentages of 17.01& 15.59% respectively, while the lowest percentage of individual number was recorded by Allonais inaequalis (0.71%). The highest individual numbers were recorded in July and August of 526 & 644 respectively. Site No.2 recorded the highest species richness (16 species) and highest individuals' number of 1127. The study was also included measure of the physicochemical parameters such as air temperature, water temperature, biochemical oxygen demand (BOD),PH, salinity, electrical conductivity (EC), ,turbidity, total suspended substance (TSS) and total dissolved substance (TDS). The result showed that the air temperature were (9.5-47) Co, water temperature (8.67-31.16)Co , BOD (0.46-4.7) mg/l,PH (7.941-8.125), salinity (0.2-0.4), EC (562-1043) ms/cm, ,Turbidity (6.92-215)NUT,TSS (1-94) mg/l and TDS(359-807)mg/l.