الفهرس 
Taxonomical resultsOnly 14 pages are availabe for public view
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Abstract
Polychaetes play an important role in the food cycle in the sea. They act as a source of organic matter after the death and disintegration. In addition, polychaetous annelid worms are by far most abundant group of fouling organisms in all harbours of the world as well as they are important source of organic matter and other elements. Moreover, polychaetes and crustacea are the most valuable fish food. These concepts were ascertained by several authors. In spite of’the presence of polychaete in huge numbers along the coasts of the Egyptian waters, they have recieved little attention especially in Port-Saied region, which is considered as an international water-way, since it communicates the Red Sea and Mediterranean one. However, the number of species collected from the Egyptian coasts appear to be relatively low, because the surveys carried out so far were both scattered and limited in time. Since this thesis is designed and has two fold purposes. The first includs a detailed taxonomical study of sedentary polychaetes forming fouling and errant polychaetes of the foul.ing community as integral part of it. Keys to the recorded genera that contained more than one Egyptian~representative species and descriptions of the new species, as well as redescriptions of the recorded species were submitted. On the other hand, the second part includs an ecological investi.gation of the fouling polychaetes including population densi 1;y; r,r:asonal and vertical distribukions; the species diversity and equitahility; relative contribution and the mutual similarities among fouling polychaete fauna. Samples were collected along successive period of 12 months,from January 1984 -till December 1984 from two different substrata, the first one is wooden boat (I ), however, the second is wooden pontoon (11,). In a order to cover one year sampling, the surface of both chosen substrata was theoretically divided into 12 equal vertical zone each about 60 crn wide. Three samples each e~ciyhted one I<. gm. were taken monthly from om zcme at I;wn d~pths (blecr 50 c:m and 200 cm of.’ the water surface). Meanwhile, with each collection, salinity and temperature of sea water as well as air temuerature were measured. The main results of this study could be summarized as follow: (1) The species compisition of distribution of recorded polychaetes were arranged in a taxonomical list comprising a total number of 26 species belonging to 8 families, 15 genera. Among these two species i.e Nere5.s (~ceratonereis) quatrignath &.n. - and Nereis (~ceratonereis) aqrmlhus -S Q.-~, were found to be neu for ..;c.i.cnci( TIE new subgenous, Aceratonereis is erected for these species), whereas four species i .e Lepidonotus cristatus? ; Syllis (Typosyllis) corallicela Nereis e ere is) heteromorpha and Polydora blake were firstly recorded in Egyptian water, and 6 species i.e. Lepidoriotus squamatus; Nereis (Nereis) ’f alsa. Nereis (nereis) unifacj.t:i.a; Nareis (Neantlier;) caudata; Staurocephalus rudolphii and CerratuLus cirratus were found to be new for locality. (2) As concerns the comparison of the two investigated biotopes the present results reveal that the diversity of the fouling polychaete fauna and the relative abundance among species were greatly influnced by the type of substrate; the depth and seasonal changes. (3) The microenviromental conditions of the habitat in which they live. This can be well illustrated by the investigation of the faunal conlposition of polychaetes and their distribution specially Lhe n~ust abundent species which represent the high intrinsic potential of the community. A total number of 26 species was recorded from four sites investigated. from the present data, it can be indicated that the qualitative statistical affinity of the fouling polychaete populations in the two used substrate was high since the number of shard species 21 and that of the species restricted the wooden boat substratum was 5 Spp. These are Lepidonotus squamatus; Lepidonatus cristatus; Nereis heteromorhpha; Nereis (~ceratonereis)q uatriqnathus and -Pol ydora ciliata. Whereas there is no restricted species to wooden poonton substruturn.