ABSTRACT
Abstract Like other meiofaunal organisms, tardigrades suffer from a significant knowledge gap concerning many aspects of their biodiversity. The lack of an up-to-date digital collection with all species and details of limnoterrestrial and freshwater tardigrades in South and Central America is one of the most critical gaps to be filled. Therefore, the present work aims to develop a database containing all valid species of limnoterrestrial and freshwater tardigrades from South and Central America found until 2023 and provide open access to the results. Data for each species were obtained directly from the literature using Google Scholar and the website tardigrada.net. This compiled data resulted in the creation of a database with the species name, author and year of species description, genus, family, class, type country, type location, coordinates (longitude and latitude), if it is aquatic and/or limnoterrestrial, substrate where it was found, the country and location of collection, and manuscript containing the species identification. Furthermore, the coordinates of each occurrence were plotted on maps with political-administrative boundaries and Neotropical and Andean biogeographic regions. In addition, statistical analysis was performed related to the geographic distribution of the sampling effort. From the literature, 2157 records of valid non-marine Tardigrada species, endemic or not, were computed. From these records, 271 species of tardigrades have been identified in the two regions combined, with 223 species in South America and 129 species in Central America. We were able to show that there are still many biases in the sampling of tardigrades in the Neotropical and Andean regions and that further studies are needed on the biogeography of these meiofaunal organisms in these biogeographic regions. We expect this database to help better understand the richness and distribution patterns of limnoterrestrial and aquatic tardigrade species in Central and South America.
Resumo Tardígrados, assim como outros organismos meiofaunais, possuem uma lacuna de conhecimento significativa acerca de muitos aspectos da sua biodiversidade. A inexistência de um acervo digital, e atualizado, com todas as espécies e detalhes de tardígrados limnoterrestres e aquáticos na América Central e Sul é uma das lacunas mais importantes a serem preenchidas. Dessa maneira, o presente trabalho tem como objetivo elaborar e disponibilizar, de maneira gratuita, um banco de dados contendo todas as espécies válidas de tardígrados limnoterrestres e aquáticos das América do Sul e América Central encontradas até 2023. Os dados de cada espécie foram obtidos diretamente na literatura, utilizando o Google Scholar e o site tardigrada.net. Com todos esses dados compilados, foi elaborado um banco de dados com nome da espécie, autor e ano de descrição da espécie, gênero, família, classe, país tipo, local tipo, coordenadas (longitude e latitude), se é aquático e/ou limnoterrestre, substrato onde foi encontrado, país coletado, local de coleta e manuscrito com a identificação da espécie. Ademais, as coordenadas obtidas de cada ocorrência foram plotadas em mapas das fronteiras político-administrativas e das regiões biogeográficas Neotropical e Andina. Além disso, uma análise estatística quanto à distribuição geográfica do esforço amostral foi feita. Da literatura, foram computados 2157 registros de espécies válidas de tardígrados limnoterrestre, endêmicas ou não. Desses registros, foram descobertas, até hoje, 271 espécies de tardígrados entre as duas regiões, com 223 espécies na América do Sul e 129 espécies na América Central. Foi possível demonstrar que ainda há muito viés na amostragem de tardígrados nas regiões Neotropical e Andina, e mais estudos acerca da biogeografia desses organismos meiofaunais nessas regiões biogeográficas são necessários. A partir desse banco de dados, espera-se contribuir para um maior entendimento da riqueza e dos padrões de distribuição de espécies de tardígrados limnoterrestres e aquáticos nas América Central e Sul.
ABSTRACT
Gastrotrichs are aquatic microinvertebrates (less than 1 mm long) commonly found in freshwater and marine environments worldwide. The taxonomy of gastrotrichs is mainly based on external morphological characters, such as body shape and size of the different body regions, presence and distribution of adhesive tubules, or the microstructure of the external cuticle (e.g. scales, spines, cephalic plates). The diversity of Gastrotricha is still poorly known, especially in tropical regions. The aim of this study is to use integrative taxonomy to report new records of Chaetonotus dadayi, C. paucisquamatus and C. furcatus from the states of São Paulo and Minas Gerais, Brazil. In this study we present 1) new records of C. dadayi in Brazil with new morphological information and a first-time comprehensive diagnosis of the species; 2) the redescription of C. paucisquamatus based on material collected at the type locality and the neotype designation; and 3) the first record of C. furcatus outside its type locality. We also discuss the actual occurrence of C. paucisquamatus and C. furcatus in Poland, given that both species were found in artificial environments with flora imported from South America.
Subject(s)
Fresh Water , Animals , Brazil , Base SequenceABSTRACT
Information regarding the records of Brazilian marine gastrotrichs is presented. We systematized and organized the existing information associated with approximately 23 species (belonging to the genera Aspidiophorus, Chaetonotus, Crasiella, Dactylopodola, Dendrodasys, Draculiciteria, Halichaetonotus, Heteroxenotrichula, Kryptodasys, Macrodasys, Pseudostomella, Ptychostomella, Urodasys and Xenotrichula) from the Brazilian coast (eight endemic) and their 1,581 records from 36 marine ecoregions of the world. A link is provided to an on-line interactive map where all occurrences for each species are shown, accompanied by geographic coordinates, oceans, countries, cities, granulometric characteristics and ecoregions. Furthermore, a critical analysis of the geographical distribution of Brazilian marine gastrotrichs, an estimate of the number of undescribed species, a summary of the existence and status of taxonomical collections are also presented.
