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OCR
122 IVIL Zoocoenological characteristics considering their structural base, and they can be corrumpents, sustinents, or intercalary catenae. An example of the first is Ceutorrhynchitena maculaealbae, of the second, Apiditena mellificae, and the third one Eccoptogastritens rugulosi. The number and kind of constituent coeti is a characteristic of a zoocoenosis. If, among the constituent populations, there is only one linked to the plant energy source, such a zoocoenosis can only be a catena. According to the coetus association of this population, it can be a corrumpent, sustinent or intercalary catena; by the number of coeti, it can be an initial, or a precedent, zoocoenosis. If, at the base level, there are more populations linked to the same plant as an energy source, the zoocoenosis is a precedent one, and it is ranked as a catenarium. If the plant base is composed of multiple species, the zoocoenosis can be considered a plenary one, with a rank of presocium or supersocion. A community that, apparently, has only a single coetus, should, in theory, be considered a catenarium or presocion. The supersocion occupies a special position because, sensu stricto, it does not have a sustinent coetus. A supersocion is not linked to a specific plant community, nor to initial links or pre-existing catenaria, but assumes the pre-existence of plenary presocia, with the plant community serving as its energy source. The sustinent elements, therefore, as an indispensable part of presocia, belong to the supersocion, as its first trophic level is the presocium itself, or its totality. 2. Coetus value The coetus value must appear among the characteristics of zoocoenosis, because the populations with multiple coetus values can increase the linkages between the members of the zoocoenosis, and can have a profound influence on its formation. The greater the coetus value a semaphoront group represents, the more independent it is from the needs of other semaphoront groups; thus, the lower the need for association, and it can fit easily into various zoocoenoses. Certain species of Formicidae, due to their coetus values of 2 or 3, can occur practically everywhere, provided that the abiotic conditions are suitable. Birds that live on insects in the summer, and seeds during the winter, can be constant in a biotope, while swallows, having a single coetus value, must move once insects become scarce. The coetus value is an important zoocoenological characteristic because the populations with higher coetus values are members of more widespread zoocoenoses, and they can have a profound influence on the changes and sustainability of various zoocoenoses, even if they are, themselves, uncommon populations.
