anomala

and may be treated as a plea for more future studies on the life cycle and other biological characteristics of this species, which would enable its mass production for aquaculture. This study aims to follow up the monthly variation of the biometric measurements of the nereid in question, as well as the sex ratio, fecundity, egg ripeness and spawning season in relation to the environmental conditions along the Alexandria coast. Two sites characterised by abundant P. anomala were selected along the Alexandria coast, namely, Abu-Qir and El-Mex ( Figure 1). Abu Qir is an exposed site on the western edge of Abu-Qir Bay east of Alexandria City, with a bottom containing a chain of natural rocks covered by a rich algal flora. El Mex is also an exposed rocky area Obeticholic Acid in vivo on the western part of the Alexandria coast; it is directly

affected by industrial, agricultural and sewage discharges. Salinity, temperature, pH, dissolved oxygen (DO) and biochemical oxygen demand (BOD) were measured concurrently with polychaete collection. Both water temperature and pH were measured in the field using a digital portable pH − °C meter (HANNA 10pH). Salinity was determined with a calibrated salinometer (Beckman, Model RS-7C). DO and BOD were determined according to the Winkler method (Strickland & Parsons 1972). The P. anomala worms were collected monthly by scraping the benthos from Buparlisib rocky substrates; the samples were placed in 5 litre plastic jars. The worms were sorted, counted and preserved in 4% buffered formalin for the biological observations and finally preserved in 70% ethanol. Several biometric parameters were measured for each monthly number of worms, namely the total length (TL), length to the 6th segment (L6S), body

width at the 6th segment (W6S), prostomium length (PL) and prostomium width (PW). In order to minimise the formalin effect, the biometric measurements were done directly after sorting. The relationships between the biometric parameters were assessed by using regression and Pearson moment correlation analyses. The length-weight relationship was determined according to the allometric equation W = aLb (Hile, 1936 and Bechamn, 1948), where ‘W’ – total body wet weight [g], ‘L’ clonidine – body length [cm], ‘a’ – a constant and ‘b’ – the growth coefficient. Numerous worms were dissected partially to define the sex and to collect eggs from females. The diameters of about 40 oocytes were measured monthly using an eye-piece micrometer; the mean diameter was calculated. Fecundity expressed as the number of eggs per female was found by counting all the ripe oocytes in the coelom of fully mature, intact, i.e. uninjured, females. Males were identified by the presence of sperm plates or sperm aggregates in the coelomic fluid, while worms without sexual products were considered immature.