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§ Seasonal aspects and plant phenology | 103 § SEASONAL ASPECTS AND PLANT PHENOLOGY It seems useful to attach the linkages of animal communities to plant phenological stages. This is desirable because the apparent populations of the catenae organised around corrumpents adapted to pterophytes often appear together for a short time; at least some populations are apparent for a short time only. After this, the corrumpents may enter a long diapause; the obstants, if they need intermediary hosts, move to another zoocoenosis. The corrumpents, especially the monophagous ones, and among them the highly-specialised ones (such as spermophages), have adapted to their host plants very closely. The parasites of the Neoglocianus (Ceutorrhynchus) maculaalba (macula-alba) only have two weeks after flowering to find their hosts in the developing poppy head (Szelényi, 1935; Schroeder and Nolte, 1952). Our own studies on Rhagoletis cerasi during 1931-1943 on the same site (Budapest, Hűvösvölgy), showed that the adults emerged precisely when the earliest cherries started to show colour. Due to the extraordinarily warm spring of 1934, the cherries ripened almost a full month earlier than in 1933 or 1935, but the cherry fruit fly tracked the phenology of its host plant. Contarinia medicaginis or C. lentis cannot provide any care of its progeny before the flowering of the alfalfa or lentils, respectively. Coincidence (Thalenhorst, 1951) is therefore essential for the population to remain part of the zoocoenosis. The seasonal aspect of the zoocoenosis, by necessity, coincides with plant phenological stages. The aspects can be delimited by the following plant phenological stages (not ignoring that these are not sharply differentiated): in the case of herbs, we distinguish; 1) seedling (until the formation of real leaves); 2) stem development; 3) flowering; 4) seed fertilisation, and; 5) seed maturation. On trees, or perennial plants, we can distinguish five phenological stages: 1) budbreak or sprouting; 2) flowering; 3) seed fertilisation; 4) seed maturation, and; 5) leaf fall. For the latter grouping, winter brings a 6" stage, while for the overwintering annuals (oilseed rape, winter cereals) this aspect is identical with the seedling stage. After harvest, herbs produce a fallow aspect, unless human activity prevents this, but this is a separate aspect only from the point of view of the phytocoenosis - but not for the animals living there. In this zoocoenosis, for example, on wheat fallow the Cephitena pygmaei is represented by the imago aspect of Norbanus scabriusculus, while the contemporary aspect of the Chloropiditena pumilionis catena is represented by the adults of C. pumilionis - Coelinius niger. These aspects are easy to distinguish in crops, but attaching a zoocoenological aspect to a plant phenological stage is much more complicated in other biotopes. Our knowledge here is rather uncoordinated, and the way of naming these species spectra (prevernal, vernal, aestival, autumnal, hyemalis, Shakleford, 1929) merely indicates the seasonal changes of the animal assemblage, and is not identical with the above-detailed zoocoenological aspect.
