Aim of this study was to investigate microhabitat preferences of epiphytes in relation to trophophytes and to exposition and location on the trunk. The study site is a cloud forest fragment, located in a river gorge in central Veracruz (19°30'N, 96°59'W) at 1550 m altitude. There, annual precipitation is 1440 mm and the average temperature is 18.0°C. Trees were marked at the end of the rainy season along four transects of 30 m length, running perpendicular to the river. All 100 trees within 2.50 m distance of the transect were checked for trunk epiphytes between 0-1.50 m height. Frequency and cover for each epiphyte species were estimated with a modified scale of Braun-Blanquet, for three ranks of 50 cm height and for the river and mountain exposed side. Most abundant tree species were the angiosperms Arachnothryx capitellata (Rubiaceae), Clethra mexicana (Cyrillaceae) and Liquidambar styraciflua (Hamamelidaceae), and the tree ferns Alsophila firma and Cyathea divergens (both Cyatheaceae), the latter two with highest cover rates of epiphytes. Most abundant epiphyte species were Trichomanes capillaceum, Trichomanes reptans (Hymenophyllaceae) and Peperomia quadrifolia (Peperomiaceae). Strongest microhabitat preferences were found between Trichomanes capillaceum and both tree fern species, while Peltapteris peltata was exclusively present on angiosperm trees. Also Trichomanes reptans occurred mostly on different angiosperm trees, and finally Peperomia quadrifolia was indifferent in relation to trophophytes. Some epiphyte genera showed preferences for only one of the tree fern species: Asplenium (Aspleniaceae) and Elaphoglossum (Lomariopsidaceae) were significantly more frequent on Alsophila firma, while Syngonium (Araceae) was more represented on Cyathea divergens. Species diversity of epiphytes was higher on the river exposed side and increased from the lower to the higher trunk sites, while the species coverage decreased.

Key words: cloud forest, ecology, epiphytes, ferns, Peltapteris peltata, Trichomanes capillaceum