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Cyanocyclas brasiliana (Deshayes, 1854) known only from the original very short description and reported from Pará state was recently rediscovered. This is the first occurrence of a native species of Cyrenidae (formerly Corbiculidae) in the Northeast Region of Brazil. Due to a lack of previous data C. brasiliana was initially confused with Corbicula largillierti (Philippi, 1844), an invasive species of Asian origin, which was introduced in South America in the 1970s and already recorded from the North and Northeast regions of Brazil. Ecological aspects are described. To aid identification, type material was studied.

Leaf litter represents a food source to many organisms that may directly contribute to organic matter decomposition. In addition, the physical presence of these vegetal detritus contributes for the modification of some environmental areas and produce microhabitats that may act as a refuge against predators and desiccation for many animals. The pulmonate gastropod Melampus coffeus (Linnaeus, 1758) (Ellobiidae) is a very common specie in Atlantic Coast mangrove forests and feeds on fallen mangrove leaves. It was hypothesized that the spatial distribution of Melampus coffeus is directly affected by mangrove leaf litter biomass deposition. Thus, this research aimed at evaluating the spatial distribution of these gastropods in relation to the biomass of mangrove leaf litter through a twelve-month period. The study area was established in the middle estuary of Pacoti River, state of Ceará, Brazil where two adjacent zones with different topographic profiles were determined. Samples of Melampus coffeus and leaf litter were collected monthly, throughout a year, from the mangrove ground surface. The results indicated that the presence of twigs in mangrove litter favor the occupation by smaller individuals of M. coffeus, probably because smaller individuals are more susceptible to predator attacks and desiccation than larger ones, and twigs and branches may provide a safe microhabitat.

In marine soft-bottom environments, the availability of hard substrates may strongly influence the reproduction of benthic species. Most marine gastropods attach egg capsules to any hard object lying on the sediment surface, but some species may choose to deposit egg capsules on living organisms. This study reports deposition of egg capsules on shells of living Tivela mactroides. We collected T. mactroides individuals in six sampling sites along a morphodynamic continuum to investigate which species was using T. mactroides as oviposition substrate as well as looking at the pattern of capsule deposition on the shells. More than 90% of T. mactroides individuals had one to 55 egg capsules on their shells, all belonging to Olivella minuta —the first record of this interspecific relationship. Most egg capsules were concentrated closer to the umbo of the bivalve (dorsal region) and there was no evident relationship between the number of egg capsules and length of T. mactroides. The number of egg capsules strongly decreased in more reflective beach conditions; however, the pattern of egg deposition on the shells was roughly similar in all sites. These findings increase our understanding of the reproductive biology of O. minuta and demonstrate the ecological importance of T. mactroides ; they also emphasize that biological interactions and density-dependent relationships may influence the community ecology of soft-bottom habitats. [ABSTRACT FROM AUTHOR]

The present paper investigates standing stock variations of Halimeda opuntia on a sandstone reef of the South-west Atlantic Ocean, in order to better understand the role of this seaweed as a CaCO3 producer. The study was conducted over two 3-month periods, using photo quadrats to analyse the coverage area, and destructive sampling to quantify area-specific biomass and CaCO3 percentage. The alga occupied 2.4% of the substrate (4464 m2), growing as clumps with an average biomass of 1.59 kg m−2, resulting in a standing stock of 7097.8 kg of alga. This standing stock varied with environmental conditions, particularly wind speed. Assuming an exponential model for these variations, H. opuntia produced at least 13,050.14 kg (54.37 g m−2 day−1) of carbonate sediments. There was a positive correlation between changes in standing stock and coverage, but not with area-specific biomass. This suggests that net algal growth results in the occupation of new spaces, with minimal increases in height or segment density. Therefore monitoring coverage should complement traditional individual-based methods for estimating Halimeda growth and production. Combined, these approaches should result in more accurate models of the role of this alga on marine carbonate budgets. [ABSTRACT FROM PUBLISHER]

The table of contents for the Volume 125, 2014 issue of "Feddes Repertorium: Journal of Botanical Taxonomy and Geobotany" is presented.

The present study records Halophila baillonis and describes the specimens of the Environmental Protection Area of the Parnaíba River Delta, Piauí, semiarid coast of Brazil. In August 2014, we mapped and characterized the seagrass meadow, and georeferenced the extent of H. baillonis patches within the area. Ten ramets were collected manually for biometric measurements, and five samples were collected using a PVC corer of 10 cm in diameter, inserted at 15 cm depth, to obtain averages of shoot density and belowground/aboveground biomass ratios. Apart from H. baillonis, we recorded Halodule wrightii, Halodule sp. and Halophila decipiens, characterizing the seagrass meadow of Cajueiro da Praia as the most diverse on the Brazilian coast. Average density was between 96 and 1401 shoots m-2; total biomass ranged from 14.3 g dw m-2 to 27.1 g dw m-2; and leaf size 7.8 to 23.8 mm. In general, density, biometric and biomass values of the plants were greater than or at the upper range described in other areas, co-occurring with other seagrass species and on a variety of sediments, indicating a well-established bed. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]