CONTRIBUTION TO THE STUDY OF PTERIDOPHYTES OF THE SERRA DO URUBÚ, MARAIAL MUNICIPALITY, PERNAMBUCO STATE, NORTHEASTERN BRAZIL (MARATTIACEAE-VITTARIACEAE)

BARROS, I.C.L, M.R. PIETROBOM-SILVA, G.S. BARACHO, J.A. SIQUEIRA, V.G. SANTOS & A.M. MOURA (2001). Contribution to the study of pteridophytes of the Serra do Urubú, Maraial municipality, Pernambuco state, Northeastern Brazil (Marattiaceae-Vittariaceae). Anales Jard. Bot. Madrid 58(2): 303-310. This paper presents a study of the pteridophytes of six families collected in one of the few remaining fragments of atlantic forest in Pernambuco, NE Brazil. 22 species of 13 genera are recorded most of which live on the ground in shady hollows. The specimens are deposited in the EAN, IPA, UFP and PEUFR herbaria.


INTRODUCTION
destroyed because of the cultivation of sugarcane.What was once an extensive and The present study is a contribution to the uninterrupted forest has been reduced to a few knowledge of the pteridophyte flora of the fragments, of which 93% is in stands of about state of Pernambuco.
10 ha, and only 7% is stands of 100 ha or The Atlantic Forest in Pernambuco, more, which includes one of the larger stands northeastern Brazil, has largely been of Atlantic Forest (CONDEPE, 1995).

CHARACTERISTICS OF THE ÁREA
The Serra do Urubú is located between 08°42'00" and 08°43'00"S, and between 35°48'00" and 35°49'00"W, within the municipal districts of Jaqueira, Maraial and Lagoa dos Gatos (fig.1).The mountain range between 700 and 1.080 m (VELOSO & GOES FILHO, 1982).It is dense shady montane forest, and habors one of the few humid forest fragments found in the southern part of Pernambuco.The numerous springs, lakes and ponds, decisive in the maintenance of the vegetation, have been greatly altered by construction of dams that supply the recently created municipal district of Jaqueira.These water sources flow into the Piranji river, one of the main tributaries of the river which crosses several municipal districts.
The complex of mountains formed by the Serra do Urubú and Serra do Espelho embraces several forest fragments with varying degrees of disturbance: Mata do Ageró, Mata da Serra do Quengo, Mata do Caranha e Mata Belarmina.These áreas differ in the amount of light that readres their interior, caused by different tree shade which creates various dark and humid microhabitats, altering the soil, relief, and other factors which influence the pteridophyte composition of the communities.The focus of the present study was the forest known as the Mata do Ageró, dominated by trees 20-35 m tall.This forest presents a wealth of species, particularly epiphytes of the families Araceae, Bromeliaceae and Orchidaceae.
For the habitats naming of the pteridophytes we have follow the classification present in AMBROSIO & BARROS (1997) and BARROS (1997).
The authors ñames of taxa have been abbreviated in accordance with patterns presented in BRUMMIT & POWELL (1992).

RESULTS
Twenty two species representing thirteen genera and six families were recorded.The data presented reflect collections from near the edges of the highway that passes through the Mata do Ageró, and from slopes within the forest.Further sampling may show better representation of the species found.On the other hand, the low number of species recorded in comparison to data from Mata da Chuva, Bonito municipality, Mata do Engenho Agua Azul, Timbaúba municipality, Serra dos Cávalos, Caruarú municipality and Mata do Estado, Sao Vicente Ferrer municipality (Barros, unpublished) may reflect different degrees of sampling in these áreas.
A larger number of species was collected on soil, with the greatest number being on soil, with the exception of the Hemionitis palmata which was terrestrial on rocks and Vittaria lineata which is an epiphyte (table 1).
The proximity of sources of water and low light may affect species dominance, and main explain high number of species of Adiantum observed.Just six species, Lygodium venustum, L. volubile, Anemia villosa, Cyathea microdonta, Dicranopteris pectinata and Pityrogramma calomelanos, occur in sites subject open to high insolation, and generally affected by human activity.The rarest species found were Danaea elliptica and Hemionitis palmata, restricted to densely shaded and humid places.These species also present restricted distribution elsewhere in Pemambuco (BARROS, 1997).