Flora vascular de um inselbergue no Município de Patos, Mesorregião do Sertão Paraibano, Nordeste do Brasil.

Abstract

Inselbergs or mountainous islands are rocky elevations generally monolithic geomorphologically formed by granites or gneisses, which resisted erosive process, and is also designated as reliefs testimonies. It features a peculiar flora which is still little known and commonly threatened by human action. This study aimed to contribute to the knowledge of the floristic richness of the inselbergs in the semiarid of the State of Paraiba, taking as a starting point the characterization of the vascular flora of these formations in the municipality of Patos, mesoregion of sertão in the State of Paraiba, northeastem Brazil, as well as highlighting the altitudinal gradients in the area study. The study was carried out at Espinho Branco Inselberg, located in the Southwest region of Patos . In order to perform the work, botanical collections were made monthly from April 2012 to July 2013, following the usual methodology in vegetal taxonomy. The Inselberg was divided into three altitudinal gradients: base (250-305m), middle portion (305.1-360m) and top (360.1-415m). The identification of taxonomic groups was performed through the morphological analysis of reproductive and vegetative characters with the aid of a microscope-stereoscope, consultation in identification keys and picture guides. Specialists in greater taxa of taxonomic complexity were consulted. All material was incorporated to the collection of the CSTR Federal University of Campina Grande herbarium. In the studied area were recorded 102 species belonging to 85 genera and 45 families. The six most representative families in number of species were: Euphorbiaceae (12 spp.), Fabaceae (12 spp.), Malvaceae (07 spp.), Convolvulaceae (06 spp.), Asteraceae (04 spp.) And Poaceae (04 spp.). The habit herbaceous was the predominant. It was also found that 12 out of the total of identifíed species are endemic to the Caatinga and 11 represent new records for the State of Paraíba. The present study reveals a high floristic richness, approaching in number of species from other surveys in Caatinga Inselbergs highlighting the necessity of conducting researches in other fields of Vegetal Biology (Phytosociology, Genetics, Physiology, etc.) and other biological groups which are present in the studied Inselberg.