Taxonomic Catalog of the Brazilian Fauna: Hydraenidae (Insecta: Coleoptera), diversity and distribution

ABSTRACT

Taxonomic data about Brazilian hydraenids are currently available open access at the Taxonomic Catalog of the Brazilian Fauna (Catálogo Taxonômico da Fauna do Brasil - CTFB) website, an online database with taxonomic information on the animal species occurring in Brazil. Based on taxonomic contributions published until September 2023, a total of 34 valid Hydraenidae species have been recorded from Brazil, 27 (79%) of which are endemic. Foreign authors have dominated the description of Brazilian Hydraenidae species (eight out of 10), and Dr. P.D. Perkins from the United States has authored the highest number of species described from Brazil (20). While the primary type specimens of species described from Brazil are predominantly deposited in non-Brazilian institutions (65%), the collection of Museu de Zoologia, Universidade de São Paulo, Brazil, has the most Hydraenidae type species (11) in the country. So far, Hydraenidae have been recorded in 19 Brazilian states. The two states with the highest hydraenid biodiversity are Minas Gerais and Bahia, with 12 and seven species, respectively. Species distribution by Brazilian biomes reveals that the Atlantic Forest is the most diverse, with 24 species (21 endemic), followed by the Amazon rainforest, with nine species (five endemic). In this study we also analyzed the potential distribution of the four Hydraenidae genera occurring in Brazil using ecological niche modeling. Our results indicate that Hydraena Kugelann, 1794 and Ochthebius Leach, 1815 have a wide potential distribution, covering a large part of the country. Otherwise, Adelphydraena Perkins, 1989 would be restricted to the Amazon and Parhydraenida J. Balfour-Browne, 1975 to the mountains of the Brazilian Shield. The knowledge on the Brazilian hydraenid fauna is still very poor: There are significant knowledge gaps, and many areas have been under-sampled. This deficiency should be addressed in future studies.

KEY WORDS:
Aquatic insects; ecological niche modeling; minute moss beetles; neotropics