OCR
§ The smallest category of a zoocoenosis: the catena | 83 To name a catena, we should always use the name of the corrumpent, sustinent or herbivorous intercalary element from which the catena in focus originates. This rank frame should be denoted by using the genitivus of the genus name and adding the end ofthe word catena to it; the species name is also in genitivus. The above-mentioned catena used as an example would, therefore, become: Ceutorrhynchitena maculae-albae, Eurybiaetena cardui and Biorrhizaetena pallidae. The use of these names covers all the populations included in the catena that are linked as stable elements to the corrumpent living in each place, biotope or oecus. The catena (never forgetting that we are dealing with populations, and not species) does not mean the circle of parasites, predators and detritivores linked to the progeny of a female corrumpent, but the whole population living in the given oecus or biotope. It is not a catena that lives on a single poppy plant but certain semaphoront groups; the whole catena is formed by the whole poppy seed head and weevil populations living on all the poppy plants of a poppy field, and the totality of detritivore and predator populations linked to these. Therefore, a catena can include a huge mass of animals and the relationships of the structural elements and, within these, the individual populations can only be clarified by appropriate study methods. A catena, therefore, can extend to a whole oecus or biotope, although not necessarily. It can occur that, on a given portion of a poppy field of several hectares, certain obstant elements, that are not present elsewhere, associate themselves into the Timaspiditena papveris catena. Two Timaspiditans catenae will, therefore, be different, and will form two facies of the same catena. The same faciesdifference may exist between the species combination of Timaspiditena in the Carpathian highlands and that of the Transdanubium. Catenae can originate from three types of elements: corrumpents, sustinents, and intercalary elements living on plant debris. Obstants will, necessarily, be attached to all three elements (the only way the catena be formed), plus occasional intercalary elements living on animal food that are not always present. To form a catena, at least two operative elements have to meet. Between these two structural elements there is a tight interaction that is reflected in population dynamics: the host population allows the attachment of obstant elements, and its abundance will have a feedback effect on the others dynamics, and the other element will also influence the density of the host population. The catena includes the obstant elements of the second and third levels. The catenae are, therefore, the most independent, and the most tightly interacting frames of the zoocoenoses. They are independent of each other and do not assume each other’s existence (except in the case of syrmatophagous intercalary catenae that appear on plants killed by corrumpent elements), but can mutually influence each other’s species spectra. For example, in the wheat field oecus, there are no catena members of the Cephitena pygmaei that could also be involved in the Oscinellaetena frit or in the Chloropiditena pumilionis catena, even if these occupy the same oecus,