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The first zoeal-stage larva of a possibly new species of mud shrimp Naushonia (Decapoda: Gebiidea: Laomediidae) was described from plankton samples taken off the Fernando de Noronha Archipelago, being the first occurrence at the oceanic islands of the Equatorial Atlantic. Five zoea I larvae were obtained and dissected for observation of mouthparts. This zoea I of Naushonia sp. is well distinguished from the first larvae of N. portoricensis (Rathbun 1901) from the Caribbean and N. cangronoides (Kingsley 1897) from the Northwest Atlantic in terms of development and setation of appendages, and possibly belongs to a new, undescribed species. The present study widens the knowledge on tropical oceanic decapod larvae and provides detailed drawings and new photographic illustrations with extended depth of field of these organisms.

Rivers as barriers to dispersal and past forest refugia are two of the hypotheses proposed to explain the patterns of biodiversity in the Atlantic Forest. It has recently been shown that possible past refugia correspond to bioclimatically different regions, so we tested whether patterns of shared distribution of bird taxa in the Atlantic Forest are 1) limited by the Doce and São Francisco rivers or 2) associated with the bioclimatically different southern and northeastern regions. We catalogued lists of forest birds from 45 locations, 36 in the Atlantic forest and nine in Amazon, and used parsimony analysis of endemicity to identify groups of shared taxa. We also compared differences between these groups by permutational multivariate analysis of variance and identified the species that best supported the resulting groups. The results showed that the distribution of forest birds is divided into two main regions in the Atlantic Forest, the first with more southern localities and the second with northeastern localities. This distributional pattern is not delimited by riverbanks, but it may be associated with bioclimatic units, surrogated by altitude, that maintain current environmental differences between two main regions on Atlantic Forest and may be related to phylogenetic histories of taxa supporting the two groups.

The current biogeographic and taxonomic knowledge on decapod larvae in tropical oceans is still very incomplete, in spite of their huge ecological and socio-economic importance. The present study reports two new records for decapod larval forms in pelagic environments off oceanic islands in the western tropical Atlantic, and provides detailed diagnoses and images of these larvae. Samples were taken from July 2010 to November 2014 using neuston, bongo and WP-2 nets at three localities: St. Peter and St. Paul's Archipelago (SPSP), Rocas Atoll (RA) and Fernando de Noronha Archipelago (FN). The larval forms Cerataspis monstrosa (Gray, 1828) and Amphionides reynaudii (H. Milne Edwards, 1832) were recorded around these areas, constituting the first record for these oceanic islands. Out of 121 samples analyzed, one specimen of C. monstrosa (Mysis II) was found off FN, and 20 specimens of A. reynaudii in nine distinct stages (Mysis II, IV, VI, VII, VIII, IX, X, XI, XII) were found off SPSP, RA and FN.