# Taxonomic Revision of the Catostemma Clade (Malvaceae/Bombacoideae/Adansonieae)

## TL;DR

This paper revises the taxonomy of the Catostemma clade, identifying 16 species and highlighting conservation concerns.

## Contribution

The study provides a comprehensive taxonomic revision and conservation assessment of the Catostemma clade.

## Key findings

- The clade includes 16 species, with 7 endemic to Brazil.
- Two species are Critically Endangered, and four are Data Deficient.
- Probable synapomorphies are discussed to clarify phylogenetic relationships.

## Abstract

The Catostemma clade comprises three genera: Aguiaria, Catostemma, and Scleronema. These genera are representatives of the tribe Adansonieae, and are part of the subfamily Bombacoideae of the Malvaceae family. Taxonomic studies of these genera are scarce and limited to isolated publications of new species or regional floras. We reviewed their taxonomy, morphology, and geography, and assessed gaps in our knowledge of this group. We carried out a bibliographic survey, an analysis of herbarium collections, and collected new material in Brazilian forests. Here, we provide an identification key, nomenclatural revisions, morphological descriptions, taxonomic comments, geographic distribution maps, illustrations, and analyses of the conservation status for all species. We also discuss probable synapomorphies of the clade, to advance our understanding of phylogenetic relationships within the Adansonieae tribe of Bombacoideae. In total, we recognize 16 species: 1 Aguiaria, 12 Catostemma, and 3 Scleronema, of which 7 are endemic to Brazil, 1 to Colombia, and 1 to Venezuela. Two species are ranked as Critically Endangered (CR), and four as Data Deficient (DD).