Morphology, Morphometry and Ecology of Moss Dwelling Testate Amoebae (Protozoa: Rhizopoda) of North and North-East India

Mosses are cryptogamous plants belonging to the Division Bryophyta and Class Bryopsida. Most of these bryophytes are gregarious and grow together in large number on soil, rocks, walls and barks of trees, often forming cushions and sometimes carpets and mats. In India maximum number of terrestrial and arboricolous moss species grow in the Himalaya, Western Ghats and other hilly areas of the country as they prefer cool and humid climate. In plains of India major part of the year is unfavourable for their growth due to high temperature and low humidity or a combination of both. In this region these mosses are restricted only to a few favourable habitats, such as, moist and shady places, banks of rivers, canals and water channels, surface walls of wells, piers of bridges and, moist and humid tree trunks. These bryophytes possess several attributes to provide suitable microhabitats for large number of diversified invertebrates, more particularly microfauna including freeliving protozoa. Mosses absorb large quantities of water, retain them and thereby retard the drying out of their underlying substrate. Thus they serve as insulation against heat, cold and wind, thereby cushioning the faunal components which live within them against climatic change. Faunal components associated with bryophytes have been divided into four categories (Gerson, 1982), namely, 1) bryobionts, i.e., animals which occur exclusively in association with bryophytes, 2) bryophiles, i.e., animals which are usually found in bryophytes but may survive elsewhere, 3) bryoxenes, i.e., animals which regularly spend part of their life cycle on bryophytes and 4) occasionals, i.e., animals which may at times be found in bryohytes, but do not depend on these plants for their survival.