Over the past 15 years, Brazil has seen a more than 200% increase in non-native mollusk species Robert Egan Senior Editor A study published in the journal Biological Invasions indicates that Brazil currently has at least 82 non-native mollusk species, in addition to 13 whose origin cannot be determined. This represents a 215% increase compared with 2011, when 26 species were reported. Twenty of these species are considered invasive because they cause ecological, socioeconomic or health damage.

Thirteen species have insufficient data to determine their impact. This is the most comprehensive inventory of non-native mollusks in Brazil. "We've observed an accelerated rate of introduction of non-native mollusks in Brazil, as well as persistent gaps in our taxonomic and ecological knowledge of those species," says Marcel Sabino Miranda, one of the authors of the study.

Miranda conducted the study during his postdoctoral research at the Oceanographic Institute of the University of São Paulo (IO-USP). The authors emphasize the urgent need to strengthen biosecurity measures, improve early detection efforts and establish long-term monitoring programs in all environments. They also argue that when impacts occur, they should be properly assessed in terms of their nature and magnitude.

"Some species, such as the golden mussel and the African snail, are problematic, but we don't know if most species are or will be harmful," says Miranda, who is currently pursuing a postdoctoral fellowship at the University of Alabama in the United States. The golden mussel (Limnoperna fortunei) likely arrived in Brazil in the early 1990s, following a long trail of invasions originating in China. Now widespread throughout South America, it causes blockages and reduced efficiency in hydroelectric plants, among other problems.

Despite being the target of a control plan, the mollusk continues to thrive. It is estimated that approximately $10 million has already been spent to combat it in Brazil. The African snail (Lissachatina fulica), on the other hand, was introduced to the country as an alternative to escargot.

However, its cultivation was abandoned, and today it is widespread throughout Brazil. It can be an agricultural pest and an intermediate host for the meningitis-causing parasite Angiostrongylus cantonensis. The researchers state that although biological invasions are identified as one of the main causes of global biodiversity loss, invasions involving this group of invertebrates are poorly documented in Brazil.

The predominant focus there is on fish, arthropods and mammals. Sea, rivers, and land The survey includes 13 cryptogenic species, whose origin cannot be determined. The caution in classification stems from the fact that many species descriptions are outdated and lack biogeographic or molecular studies to determine their origin with certainty.

The nomenclature helps avoid confusion, such as that which occurred regarding the mussel species Perna perna. Found along the entire Brazilian coast and farmed for human consumption, Perna perna was once believed to have been introduced to Brazil by humans, since the species also occurs in Africa, its region of origin.