Apple snails (Ampullariidae: Pomacea) native to the New World have become agricultural and environmental pests widely in southern and eastern Asia since their introduction in about 1980. Although their impacts have been extensively documented, considerable confusion persists regarding their identities and geographical origins. Efforts to resolve the confusion have suffered from inadequate taxonomic and geographical sampling from both native and introduced ranges. Using phylogenetic and genealogical methods, we analysed 610–655 bp of cytochrome c oxidase subunit I DNA sequences from 783 apple snails from 164 Asian locations and 57 native South American locations. In Asia, we found four species of Pomacea in two clades: (1) Pomacea canaliculata and P. insularum, and (2) P. scalaris and P. diffusa. Parsimony networks and mismatch distributions indicate that the non‐native ranges of the two most widespread species, P. canaliculata and P. insularum, probably result from multiple introductions. Molecular analyses are consistent with early accounts; non‐native P. canaliculata populations trace back to multiple locations in Argentina and have probably been introduced more than once. In contrast, P. insularum was probably introduced from Brazil and Argentina independently. Multiple introductions may, in part, explain the success and rapid spread of these two species. Unlike P. canaliculata and P. insularum, P. scalaris and P. diffusa were probably introduced through the aquarium trade, derived originally from Argentina and Brazil, respectively. Possible physiological, ecological, and native range differences among these four species highlight the importance of accurate identification in understanding invasion patterns and processes, which is vital in developing and implementing management strategies.

Ampullariidae comprises two lineages of freshwater gastropods: one Old World and one New World. Recent molecular work confirmed the monophyly of the

Eosinophilic meningitis (EoM) is an acute disease that affects the central nervous system. It is primarily caused by infection with the nematode Angiostrongylus cantonensis. This infection was previously restricted to certain Asian countries and the Pacific Islands, but it was first reported in Brazil in 2007. Since then, intermediate and definitive hosts infected with A. cantonensis have been identified within the urban areas of many states in Brazil, including those in the northern, northeastern, southeastern and southern regions. The goals of this review are to draw the attention of the medical community and health centres to the emergence of EoM in Brazil, to compile information about several aspects of the human infection and mode of transmission and to provide a short protocol of procedures for the diagnosis of this disease.