Supplemented descriptions are given for the genus Parvimysis Brattegard, 1969, and its freshwater species P. pisciscibus Henderson & Bamber, 1983, from the Amazon system upstream of the Rio Negro-Solimões confluence. Six new species are described from this range, based on differences regarding eyes, antennae, modified spines in the foregut, fourth male pleopod, and telson. A total of nine freshwater Mysidae species are now known from the Amazon Basin, revealing this system among world’s most species-rich in freshwater mysids. At least five species have the static bodies mineralized with vaterite, a metastable polymorph of crystalline calcium carbonate. The oostegites of at least six Parvimysis species show few setae but are exceptional in exhibiting discoidal structures for the attachment of eggs and larvae. A key to the Mysidae of Amazonia is provided, including keys to all currently known species of Parvimysis and Surinamysis Bowman, 1977. |
