Process and Pattern in Cladonia Subcervicornis

Abstract

Morphogenesis of podetia in Cladonia subcervicornis is a non-linear, repeating process based upon a pattern of meristem enlargement and division. Variability in mature podetia of C. subcervicornis, which may appear branched or scyphoid, is the result of variation early in ontogeny. The growth pattern of C. subcervicornis represents a continuum of developmental stages. It is impossible to predict the form of the mature thallus of C. subcervicornis because growth in this species is fluid. The morphology of the mature thallus of C. subcervicornis is difficult to circumscribe using conventional Cladonia terminology, because the processes that form the thallus are dynamic and heterogeneous. The meristem shapes that are produced during early ontogeny in C. subcervicornis are relatively simple, and the processes by which they are formed are uncomplicated. Yet podetial form in C.subcercicornis is difficult to interpret.