A flora hepática (Hepaticae, Bryophyta) da Estação Científica Ferreira Penna, na Floresta Nacional de Caxiuanã, Pará

Abstract

In the 33,000 hectares of the Ferreira Penna Scientific Station, a great diversity of ecosystems can be observed, such as várzea forests, igapós, dense terra firme forests, savannoid vegetation, and capoeiras. A study of the floristic diversity of trees in 9 hectares of dryland forest inventoried 4,803 trees with DBH equal to or greater than 10 cm, distributed in 65 families, 231 genera and 645 species, representing a high floristic diversity (188 species per hectare on average). In this work, the aim is to test the hypothesis that the diversity of hepatic trees in the ECFPn corresponds to its high tree diversity. At the same time, to carry out taxonomic studies, frequency, main associations and preferred substrates. The methodology consisted in collecting liverworts from different ecosystems, writing down data on substrates, types of existing associations, subsequent drying of the material and its identification, using specialized bibliography and/or comparison with identified material from the Herbarium MG. The results found refer only to the Lejeuneaceae family. A total of 789 specimens were identified, belonging to 33 species and 22 genera. Two genera, Ceratolejeunea and Lejeunea, are represented by 4 species each, while Prionolefeunea presented 3 species. The other genera occurred with 1 or 2 species. Arcbilejeunea fuscescens (Hampe ex Lehm.) Fulford, Ceratolejeunea minuta Dauphin, Pictolejeunea pícta (Gottsche ex Steph.) Grolle, Tracbylejeunea sp. and Ceratolejeunea cornuta (Líndenb.) Schiffn.were the most frequent, with 50, 70, 75, 105 and 127 occurrences, respectively. Eight species can be considered rare because they were found only once. With the continuation of the identifications, including the other families of liverworts, the diversity of this group should reach very significant numbers.