Preface: How far has Neotropical Ichthyology progressed in twenty years?

Abstract

Studies on the diversity, taxonomy, phylogeny, and biogeography of Neotropical Fishes have thrived over the twenty years that have elapsed since the first symposium on their phylogeny and classification in Porto Alegre, Brazil. Here, we review recent advances in the study of Neotropical fishes and assess the known diversity of freshwater species in that region. 6,255 valid freshwater species have been discovered in the Neotropics so far, and we estimate that over 9,000 species will be known when the inventory is complete. We also summarize the events of the second Symposium on Phylogeny and Classification of Neotropical Fishes that took place last year in Londrina, Brazil. Along with invited talks on the biodiversity of all major groups of Neotropical fishes, a series of presentations on the development of fish collections, and numerous contributed talks, the meeting included a special session to honor Dr. Richard Vari, who was one of the most prolific and beloved members of our community.

Checklist of the ichthyofauna of the Rio Negro basin in the Brazilian Amazon

“…Despite this improvement in the knowledge about the fish fauna in the basin. A considerable number of species still await to be inventoried, discovered or formally described, as already pointed out by Bohlke et al (1978), Ota et al (2015) and Birindelli and Sidlauskas (2018) regarding the neotropical ichthyofauna.…”

“…However, this number possibly will increase significantly with the addition of ichthyofaunal inventories in poorly sampled areas; with the accumulation of taxonomic reviews; and with the use of novel information derived from molecular and other analytical tools. The true species richness in the Amazon basin may rise to approximately 4,000–5,000 species in the next 40 to 70 years, if the description rate remains at the current level (see Ota et al (2015) for an estimative for Siluriformes; and Birindelli and Sidlauskas (2018) for freshwater fishes in Neotropical region).…”

A new inventory for fishes of headwater streams from the rio das Cinzas and rio Itararé basins, rio Paranapanema system, Paraná, Brazil

“…The Neotropical region, the most ichthyologically rich biogeographical domain in the world, comprises about 9,000 fish species (Birindelli & Sidlauskas 2018). Of these, many are small and inhabit mostly low-order watercourses (Castro 1999;Winemiller et al 2008), which are estimated to harbor about 50% of the freshwater fish richness in the tropics (Lowe-McConnell 1999;Winemiller et al 2008).…”

Ichthyofauna of the Mata de Itamacaoca, an urban protected area from the upper Munim River basin, Northern Brazilian Cerrado

“…The Neotropical freshwater ichthyofauna is the most species-rich of the world, comprising more than 6,000 described species, with estimates of over 9,000 species (Reis et al 2016, Birindelli & Sidlauskas 2018, Castro & Polaz 2020. Within this huge species assemblage, most (about 70%) are small-sized fishes, with adults around 15 cm or less standard length (SL), which can inhabit a variety of aquatic environments, such as streams, small and large rivers, lagoons, pools, temporary pools, swamps, amongst others (Reis et al 2003, Castro & Polaz 2020.…”

“…Within this huge species assemblage, most (about 70%) are small-sized fishes, with adults around 15 cm or less standard length (SL), which can inhabit a variety of aquatic environments, such as streams, small and large rivers, lagoons, pools, temporary pools, swamps, amongst others (Reis et al 2003, Castro & Polaz 2020. Literature concerning the diversity and evolution of the Neotropical ichthyofauna has improved in recent years; however, studies are still few and underestimate their real biodiversity (Buckup et al 2007, Reis et al 2016, Birindelli & Sidlauskas 2018, Malabarba & Malabarba 2020. In addition to the lack of taxonomic and ecological knowledge, the rapid loss and degradation of natural environments as a result of anthropogenic drivers (i.e.…”