RESUMO Blechnum heringeri Brade é uma espécie endêmica do Brasil anteriormente considerada vulnerável. Até pouco tempo atrás, o número de registros dessa espécie era muito limitado e restrito ao Domínio Fitogeográfico do Cerrado, no Brasil central. Coletas recentes registraram a espécie nos campos rupestres sobre cangas, no Domínio da Amazônia. Neste trabalho, apresentamos um novo registro de B. heringeri em um encrave de vegetação de cerrado dentro do Domínio da Caatinga, no Nordeste do Brasil (Estado do Ceará). Este novo registro estende significativamente a área de distribuição da espécie, distando cerca de 1.000 km dos registros nos Domínios Fitogeográficos do Cerrado e Amazônico. Os dados evidenciam a sua associação com vegetações abertas: nominalmente vegetação de cerrado, encraves de cerrado em meio à Caatinga e à Amazônia, e campos rupestres sobre canga na Amazônia ou ambientes de transição com florestas ribeirinhas.

ABSTRACT Blechnum heringeri Brade is an endemic species from Brazil previously considered vulnerable. Until recently, there was a very limited number of records for this species, all from the Cerrado Phytogeographical Domain in central Brazil. Subsequent studies have reported its occurrence in the rupestrian grasslands (campos rupestres) on the “cangas”, within the Amazonian Domain. Here we present the first record of B. heringeri for northeastern Brazil, from an enclave of cerrado vegetation in the middle of the Caatinga Domain (Ceará State). This new record significantly extends the distributional range of the species, about 1,000 km from the known records in the Amazon and Cerrado Phytogeographical Domains. We also show that the species is associated with open vegetation or the transition between open vegetation and riverine forests, being recorded in cerrado vegetation, riverine forests associated with the cerrado, cerrado enclaves in the Caatinga and Amazonian Domains, and Amazonic campos rupestres on “canga”.

The study of fossils has made considerable progress over the last years as a result of the use of new experimental techniques. This paper describes the chemical composition of a fossilized fish of the Cretaceous period, from a 100 million-year-old, material originated from the Araripe Basin (northeastern Brazil). The chemical composition of the fossilized fish was analyzed by means of X-ray powder diffraction and Fourier transform infrared spectroscopy (FT-IR). The spectroscopic study has proven that the main substances found in the fossilized fish are CaCO3 and Ca5(PO4)3(OH). A tentative mechanism to explain the fossilization process is also given.

Coprolites are fossilized faeces that constitute an important source of palaeobiological informations. This paper describes the characterization of some coprolite materials originated from the Romualdo Member of the Santana Formation (Araripe Basin, south of Ceará State in Brazil) by means of two techniques: X-ray powder diffraction and Fourier transform infrared spectroscopy (FT-IR). This characterization allowed us to determine the main composition of the coprolites, of the nodulus (where the coprolites were extracted) and of the sediment (where the nodulus was found) suggesting that the material was produced by a carnivorous fish of the Lower Cretaceous.