Communities Structure of Reef Corals
273
occupied largely by coralline algae and by gorgonians. The coral
communities there are usually impoverished. Nevertheless, in the GBR
reefs these biotopes are inhabited by ca. 150 species of corals, most of which
are hermatypic and contain symbiotic algae. Among them are Montipora,
Cyphastrea, Goniastrea, Pavona, Stylophora, Turbinaria, Echinophyllia,
Favites, and Agaricia. Besides these for other reef zones common corals, the
shadowed biotopes are inhabited by really scyophylic hermatypic
scleractinians, like Leptoseris hawaiensis, L. glabra, L. mycetoserioides, and
Pashyseris speciosa. Among the ahermatypic corals usually the there are
sciophylic scleractinia: Tubastrea, Dendrophyllia, Phyllangia, Astrangia,
Madracis, and Balanophyllia (Vasseur 1974; Jackson 1977; Jaubert and
Vasseur 1974; Rogers 1979b; Dinesen 1983; Kuhlmann 1983).
In communities of corals in deep zones of outer reef slopes the species
diversity and the number of species often remain high even at very weak
illumination: 3-10% PARS. For example, at reefs of Eilat their number
in this zone was three times higher than in the medium-depth zone of slope
and five times higher than in the lagoon (Mergner and Schuhmacher 1974).
Even by this weak light at the base of the outer reef slope over 90% of
all coral species consist of the common hermatypic scleractinians, adapted
to a low level of illumination (Titlyanov and Latypov 1991). Only about
8-10% of obligate sciophylic hermatypic or ahermatypic corals, which
live only in deep zones of the reef. Among the first most numerous group of
corals which inhabit the deep fore-reef zone on reefs of the Indo-Pacific
common are Stylophora mamillata, S. kiihlmanni, Porites australiensis,
Leptastrea transversa, Asteropora myriophthalma, Pavona varians, Echinopora lamellosa, Fungia granulosa, Pocillopora solida, Synarea convexa
and some species from the genera Podabacia, Coscinarea, and Mycedium
(Dinesen 1977; Bouchon 1981; Titlyanov et al. 1981, 1988c; Kuhlmann 1983;
Dubinsky et al. 1984; Fricke and Meischner 1985). When living in this
zone these corals build very fine and thin, flat and incrusting forms of
colonies adapted to intercepting weak light and needing less calcareous
material for their construction (Fricke and Schuh maher 1983; Titlyanov
1987; Titlyanov and Latypov 1991). Physiological mechanisms of their light
adaptation will be discussed below (ct. Sect. 8.4). Deep-water coral associations on the Atlantic reefs include the following corals: Agaricia sp.,
Scolymia sp., Madracis formosa, and Montastrea cavernosa (Kuhlmann
1983). The specific deep-water coral associations are dominated here by
specialized hermatypic sciophylic species of Leptoseris (L. mycetoserioides,
L. explanata, L. porosa). They have a special light-absorbing system
and may survive at light intensity levelS as low as 1-3% PARS (Fricke
and Schuhmacher 1983; Schlichter et al. 1985). This associations include
also the hermatypic sciophyles Cycloseris cyclolithes, C. patelliformis,
Pashyseris rugosa, P. speciosa, Leptastrea biwickensis and the ahermatypic
corals Dendrophyllia, Tubastrea, Astrangia solitaria, and Phyllangia
americana.
273
occupied largely by coralline algae and by gorgonians. The coral
communities there are usually impoverished. Nevertheless, in the GBR
reefs these biotopes are inhabited by ca. 150 species of corals, most of which
are hermatypic and contain symbiotic algae. Among them are Montipora,
Cyphastrea, Goniastrea, Pavona, Stylophora, Turbinaria, Echinophyllia,
Favites, and Agaricia. Besides these for other reef zones common corals, the
shadowed biotopes are inhabited by really scyophylic hermatypic
scleractinians, like Leptoseris hawaiensis, L. glabra, L. mycetoserioides, and
Pashyseris speciosa. Among the ahermatypic corals usually the there are
sciophylic scleractinia: Tubastrea, Dendrophyllia, Phyllangia, Astrangia,
Madracis, and Balanophyllia (Vasseur 1974; Jackson 1977; Jaubert and
Vasseur 1974; Rogers 1979b; Dinesen 1983; Kuhlmann 1983).
In communities of corals in deep zones of outer reef slopes the species
diversity and the number of species often remain high even at very weak
illumination: 3-10% PARS. For example, at reefs of Eilat their number
in this zone was three times higher than in the medium-depth zone of slope
and five times higher than in the lagoon (Mergner and Schuhmacher 1974).
Even by this weak light at the base of the outer reef slope over 90% of
all coral species consist of the common hermatypic scleractinians, adapted
to a low level of illumination (Titlyanov and Latypov 1991). Only about
8-10% of obligate sciophylic hermatypic or ahermatypic corals, which
live only in deep zones of the reef. Among the first most numerous group of
corals which inhabit the deep fore-reef zone on reefs of the Indo-Pacific
common are Stylophora mamillata, S. kiihlmanni, Porites australiensis,
Leptastrea transversa, Asteropora myriophthalma, Pavona varians, Echinopora lamellosa, Fungia granulosa, Pocillopora solida, Synarea convexa
and some species from the genera Podabacia, Coscinarea, and Mycedium
(Dinesen 1977; Bouchon 1981; Titlyanov et al. 1981, 1988c; Kuhlmann 1983;
Dubinsky et al. 1984; Fricke and Meischner 1985). When living in this
zone these corals build very fine and thin, flat and incrusting forms of
colonies adapted to intercepting weak light and needing less calcareous
material for their construction (Fricke and Schuh maher 1983; Titlyanov
1987; Titlyanov and Latypov 1991). Physiological mechanisms of their light
adaptation will be discussed below (ct. Sect. 8.4). Deep-water coral associations on the Atlantic reefs include the following corals: Agaricia sp.,
Scolymia sp., Madracis formosa, and Montastrea cavernosa (Kuhlmann
1983). The specific deep-water coral associations are dominated here by
specialized hermatypic sciophylic species of Leptoseris (L. mycetoserioides,
L. explanata, L. porosa). They have a special light-absorbing system
and may survive at light intensity levelS as low as 1-3% PARS (Fricke
and Schuhmacher 1983; Schlichter et al. 1985). This associations include
also the hermatypic sciophyles Cycloseris cyclolithes, C. patelliformis,
Pashyseris rugosa, P. speciosa, Leptastrea biwickensis and the ahermatypic
corals Dendrophyllia, Tubastrea, Astrangia solitaria, and Phyllangia
americana.