DIVERSIDADE DE HEPÁTICAS TALOSAS NO CERRADO BRASILEIRO DO PARQUE NACIONAL CHAPADA DAS MESAS, MARANHÃO, BRASIL.

Abstract

Chapada das Mesas National Park is one of the youngest National Parks in Brazil, created by the presidential decree of the year 2005, it gathers diverse rock formations and inside it houses a large number of springs, streams and waterfalls. In addition to fighting one of the most biodiverse areas of the Brazilian Savanna of Maranhão. However, with the advance of the agricultural and livestock frontier in the region, all this diversity may be threatened. In order to understand the diversity of liverworts in the Chapada das Mesas National Park, we carried out four expeditions in the years 2017 to 2020 in wet areas of the park. Our objectives were to describe the species of tall liverworts found in and around the park area, as well as the environments of occurrences and substrates of the species. In total, more than 350 samples of bryophytes were collected and seven species of thalloid liverworts were separated and identified, with five new records for the state of Maranhão, two for the Northeast region and two for the Brazilian Cerrado. The liverworts of the region showed a certain preference for rocky substrates, followed by terrestrial and dead trunks, they were always found in open areas with a high level of humidity, such as waterfalls. The species collected comprise 24% of the diversity of thalloid liverworts species in the Brazilian Savanna, 16% of the diversity of the Northeast, and represent an increase of 57% in the number of species known to Maranhão.