contain many ol igochaetes. Of the forms of marine origin, most 

 characteristic dre specialized families of amphipods, isopods, decapods, 

 and gastropods. Typical are isopods: Porcellio scaber , species of the 

 genera Halophiloscia , Detonella , Trichoniscus and particularly the most 

 primitive of the isopods, found only on the sea coast, the Ligiidae 

 (genus Ligia ). Of the amphipods, for loose soils the Talitridae (genera 

 Tal itrus , Orchestia , Talorchestia , Orchestoidea ) are characteristic. On 

 various soils, gastropods diVe encountered, primarily the Truncatel 1 idae 

 and Assimineidae (Truncatella , Cecina , Assiminea , Ovassiminea , etc.). 

 For the tropical supral i ttoral on friable soils, the running crabs 

 Ocypode , Sesarma , etc., land hermit crabs Coenobita and representatives 

 of a special suborder of isopods, the Tyloidea ( Tylos , Hel leria ) are 

 quite characteristic. The Tylos species inhabit the coastlines of our 

 seas as well--the Black Sea and Japan Sea. 



Clusters of blooming vegetation develop in silty soil, such as the 

 glassworts ( Sal icornia , Plantago maritima , Arthrochemum , etc.) and, in 

 the tropics, mangroves. 



A significant portion of the animals in this zone are scavengers. 

 According to 0. B. f'takiyevsky (1969), the biomass and population of 

 species of land origin in the supral i ttoral are both low, not over a few 

 tenths of a gram per m'^. Groups of marine origin, particularly the 

 Talitridae, provide much of the biomass in the temperate zone: up to 1 

 kg/m , with a population density of as much as a hundred thousand 

 individuals per m^. In the tropics, the biomass of the Ocypodidae and 

 Coenobita is rarely over a few tens of grams per m^ (^tokiyevsky, 1969). 



1.6 Littoral Biota. Rocky Intertidal Zone 



The communities of the supral i ttoral edge in areas with weak or 

 moderate surf usually occupy the upper stages of the highest horizon of 

 the intertidal zone and the lower portion of the supral ittoral zone. 

 Most characteristic for this area Are the Littorinidae gastropods, and, 

 in the tropics, the Neritidae. Therefore, the supral ittoral edge is 

 frequently called the littorine zone. The supral ittoral wood lace Ligia 

 is also frequently found here. 



In the lower boreal European intertidal zone (La Nbnche, coast of 

 Britain), below the supral ittoral zone there is usually a band of 

 lichens of almost black color, dominated by Verrucaria maura and Lichina 

 conf inis . In the lower portion of the lichen band, the quantity of 

 Littorina neritoides and _L. saxatil is increases, as well as mites, the 

 springtails Petrobius maritimus and the shore isopods Ligia oceanica . 

 Of the algae, in areas of surf, films of blue-green algae develop 

 ( Calothrix , etc.), plus small green algae and the red algae ( Ulothrix , 

 Urospora , Bangia ), in places the larger Porphyra and Enteromorpha . In 

 the lower portion of the supral ittoral edge, we always begin to see 

 species characteristic of the upper portion of the eul ittoral section: 

 Pelvetia canal iculata , Fucus spiralis , Lichina pygmaea , less frequently 

 Chthamalus stellatus and Fucus distichus (Lewis, Powell, 1960; Lewis, 

 1972) . TrT protected habitats, the width of the supral ittoral edge is 

 only a few centimeters, but on an open coast, it is greatly expanded by 

 the action of the surf. 



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