A tiny rediscovery in the Land of Giants: a new combination in Giuliettia (Eriocaulaceae, Poales) and other implications of finding Paepalanthus minimus again

Serra do Padre Ângelo, a quartzitic massif in eastern Minas Gerais, Brazil, was nicknamed “Land of Giants” due to the gigantism observed in some plant species found in its campos rupestres. During fieldwork for the floristic inventory of this Serra, a small Eriocaulaceae species was collected. Initially it was believed to be a new species, but a thorough revision of names and type specimens revealed that it was conspecific with Paepalanthus minimus.

This taxon was known only from the type specimen collected over 100 years ago and more than 200 km distant from the new collections. It had been overlooked in previous studies dealing with the family in Brazil, which could be explained by its diminutive size and the poor conditions of the type specimen. Here we present the implications of this rediscovery, including the combination of P. minimus in Giuliettia, a genus recently proposed based on general habit, inflorescence and seed morphology.

We also present information on distribution and ecology and briefly discuss the biogeographical pattern that could explain this rediscovery far away from the previous record. Considering its likely local extinction at the type locality and threats to the quality of its remaining habitat, the species is preliminarily assessed as Critically Endangered. This highlights the urgent need for conservation actions to protect Serra do Padre Ângelo and its unique biodiversity.