Zooarchaeological collections from shell mounds in Rio de Janeiro (2,470-4,632 cal BP) contain a high prevalence of swollen fish bones belonging to the Atlantic spadefish (Chaetodipterus faber), crevalle jack (Caranx hippos) and fat snook (Centropomus parallelus). Given the lack of knowledge of the bone degenerative process in senile fishes, this study analysed hyperostotic bone in zooarchaeological and modern specimens to obtain high-resolution morphology and microstructure reconstruction. We used microCT as well as X-ray diffraction to characterize the crystallographic changes associated with fish senility. Our results showed that trabecular microstructures in hyperostotic bones were consistent with estimated values of the per cent bone volume-to-total volume ratio (BV/TV) and were greater than 60% in cortical bone. Hyperostotic bones indicated a high radiograph density, and X-ray diffractograms showed a decrease in hydroxyapatite [Ca (PO ) (OH) ] and calcite (CaCO ) neocrystallization. These crystalline and density changes revealed an advanced stage of fish senile and indicate the vulnerability of ageing fish populations.
Three new species of Smicridea McLachlan 1871 are described and illustrated based on specimens collected in Parque Nacional da Serra da Canastra and its surrounding area, Minas Gerais state, southeastern Brazil. Smicridea (Rhyacophylax) necator sp. nov. possibly belongs to the S. (R.) dispar Group, but its placement in this group is weakly supported; S. (Smicridea) franciscana sp. nov. belongs to the S. (S.) nigripennis Group based on morphology of the phallus; S. (S.) sepala sp. nov. is a member of the S. (S.) fasciatella Group, also based on the morphology of the phallus. A new record of S. (S.) sattleri Denning & Sykora 1968 is provided for Minas Gerais state, Brazil.
Although the world species diversity of Marilia Müller 1880 is not great, knowledge about this group may be underestimated, since several areas are poorly studied, especially in Northeast Region, Brazil. Two new species are described and illustrated here based on specimens collected in Maranhão State, from which the genus has not been reported previously. Despite the similarity of Marilia caramuru sp. nov. with M. elongata Martynov 1912, differences between them are observed especially in segment X and preanal appendages, in addition to details of wing venation. The unique set of spiniform projections on endotheca, and the wrinkled prominence on sternum VIII distinguish Marilia paraguassu sp. nov. from all other species in the genus. The material examined has been deposited in the Coleção Entomológica Professor José Alfredo Pinheiro Dutra, UFRJ, Rio de Janeiro, Brazil, and in the Coleção Zoológica do Maranhão, UEMA, Maranhão, Brazil.
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