Abstract The new bulimulid species, Drymaeus currais sp. nov., is described based on shell and anatomical features. It is endemic of Guapirá Island, belonging to the Currais Archipelago, a small protected area off Paraná coast. The species is thus, based at least on endemicity, endangered. It has as closest species D. castilhensis, another endemic species of Castilho Island, ~70 km northwards. Its main exclusivities are a banded shell (except for periumbilical area); a ureter ~1/3 opened (furrow); an external anus; a slightly different buccal and intestinal arrangement; a penis lacking internal chambers; a small receptacle with a genital appendix. Zoobank Register: urn:lsid:zoobank.org:pub:25B25A8B-CED0-4284-A799-5383998BE481.

Abstract The genus Mytilus comprises a large number of bivalve mollusk species distributed throughout the world and many of these species are considered invasive. In South America, many introductions of species of this genus have already taken place, including reports of hybridization between them. Now, the occurrence of the Mediterranean mussel Mytilus galloprovincialis is reported for the first time from the Brazilian coast. Several specimens of this mytilid were found in a shellfish growing areas in Florianópolis and Palhoça, Santa Catarina State, Brazil. Morphological analysis of the shells and molecular analysis through sequencing of the cytochrome oxidase subunit 1 (COI) confirmed the taxonomic identification. The species is known for its great invasive potential and can become a major environmental problem for seafood business and coastal communities, as it can compete and even hybridize with local species.

Abstract Exotic species are those that occur in an area beyond their natural limit and they are considered invasive when they cause harm to the economy, environment, or human health. In coastal environments, ballast water and inlays on the hull and other parts of vessels are the main ways of introducing invasive aquatic alien species. Nassarius foveolatus (Dunker, 1847) is native from the Central and East Indian Ocean to the East China Sea. The first specimens (empty shells) of N. foveolatus were collected manually on November 11, 2017 on the Rocio footbridge, located in the Paranaguá Estuarine Complex, on the coast of the State of Paraná, southern Brazil. Posteriorly, live specimens were collected in other localities of this bay. It is already possible to infer that the specimens of N. foveolatus occur together with the native specimens of N. vibex (Say, 1822), having the same niche. As previously only N. vibex existed in that place, at least a displacement of this native species has been occurred. However, certainly future ecological studies may confirm this displacement and additional consequences to the local ecosystem, as nassariids can be predators and scavengers. Control procedures should be also greatly implemented.