BRYOZOAN GROWTH HABITS - CLASSIFICATION AND ANALYSIS

Bryozoans are an important part of the benthic marine fauna in a wide variety of modem environments and are found in rock forming abundance in a number of settings throughout much of the Phanerozoic. Bryozoolog ists and nonspecialists have grouped taxa into colonial growth forms ( e.g., erect fenestrates or encrusting sheets), both to simplify analys es and because correlations exist between some colony growth forms and the environmental conditions in which the organism lived. These corre lations allow for the possibility of paleoenvironmental analyses based on skeletons alone. Existing bryozoan colonial growth form classifica tions do not, however, fully exploit the ecological information presen t in colony form. A new scheme is proposed here (Analytical Bryozoan G rowth Habit Classification), which provides a list of colony-level mor phological characteristics for bryozoan growth habits: This differs fr om previous approaches to bryozoan growth form analysis in that it is a classification of growth habit characteristics rather than a classif ication of morphological groups as such, The classification is based o n eleven character classes, which describe the orientation of the colo ny and its occupation of, and placement in space. The overall colony s hape is described based on the arrangement of modules in colonial grow th. This classification provides a common ground for systematic compar ison of character states among varied bryozoan growth habits. This app roach allows for the evaluation of correlations among observed morphol ogical character states and specific environmental conditions in which they develop. In addition, these growth habit characters can be used to recognize, characterize, evaluate, and apply mom traditional growth form groups in broader studies.