Redescription of Tardigrades from Campos do Jordão Described Between 1930 and 1950: Integrative Taxonomy and Neotype Designation for Species Originally Described by Dr. Rosina de Barros

• Grant number: 25/07649-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: André Rinaldo Senna Garraffoni
• Grantee: Eduardo Klinke da Cruz
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 23/05724-9 - Overcoming linear and wallacean shortfalls in neglected meiofaunal taxa: an integrated view on biodiversity of the phyla Gastrotricha and Tardigrada, AP.BTA.R

Abstract

The taxon Tardigrada, belonging to the supertaxon Panarthropoda and commonly known as "water bears," comprises minute organisms (50 to 1200 ¿m) with a robust, barrel-shaped body covered by a non-calcified cuticle. They possess four pairs of locomotor appendages equipped with claws or adhesive glands and a specialized buccopharyngeal apparatus. Tardigrades are remarkable for their ability to enter cryptobiosis, a state that allows them to withstand extreme conditions of temperature and pressure. With over 1,488 species catalogued, tardigrades inhabit a wide variety of ecosystems and display a global distribution. This broad distribution, coupled with the lack of preserved specimens in museums and outdated species descriptions, has contributed to the notion of cosmopolitanism in some species. However, new techniques and technologies have increasingly challenged this concept.In Brazil, tardigrades were first studied between the 1930s and 1950s by pioneering researchers such as Rosina de Barros, Eveline Du Bois-Reymond Marcus, and Ernst Marcus. Despite limitations such as low-quality equipment, difficulties in specimen preservation, and the absence of deposited type series, these scientists managed to describe 11 new species. Using modern morphological analysis techniques-such as differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM)-in conjunction with molecular methods, including the sequencing of nuclear and mitochondrial genes, this study aims to adopt an integrative taxonomic approach to redescribe the species originally studied by Dr. Rosina de Barros.This approach will allow for the updating of species descriptions and the acquisition of information that was inaccessible 70 years ago. The integration of morphological and molecular data has proven essential in addressing challenges such as the identification of species complexes and the reorganization of phylogenetic relationships. Finally, new type series (neotypes) will be designated and deposited in the collection of the Museum of Biological Diversity (MDBio) at UNICAMP, and the nuclear and mitochondrial gene sequences of the Brazilian specimens will be submitted to GenBank. (AU)