Gabriel Nakamura , Bruno Henrique Stabile, Livia Estéfane Frateles, Matheus Lima Araujo, Emanuel Neuhaus, Manoela Marinho, Melina de Souza Leite , Aline Richter, Ding Liuyong, Tiago Magalhães da Silva Freitas, Bruno Eleres Soares , Weferson Júnio Graça, José Alexandre Felizola Diniz-Filho

Ecological and evolutionary processes are recognized as the main factors generating and maintaining biodiversity. However, how biodiversity knowledge is collated, organized, and distributed worldwide influences our perceptions and inferences about biodiversity and the underlying processes. We demonstrated that name-bearing type specimens (NBT), the most fundamental reference for the identity of any species, of all freshwater and brackish fish species in the world are mostly housed in museums in Global North countries. The unequal distribution of NBT results from historical and socioeconomic factors and has implications for both the Global North and South countries. For the Global North, which concentrates most of NBT, we found a mismatch between NBT housed in their ichthyological collections and their native biotas. On the other hand, countries with most NBT of their native species housed elsewhere face a barrier in advancing biodiversity research due to the difficulty in accessing reference material, hampering global efforts in cataloguing, reviewing, and describing new species. We advocate that if we are truly committed to advancing biodiversity research, we should pursue global initiatives to make the distribution of biological knowledge fairer among countries, which involves programs for specimen repatriation and facilitation of accessibility of NBT material to researchers from the countries in which they were collected.