From Herbarium to Landscape: New Records and Mapping Rare and Threatened Species of Brazilian Atlantic Rainforest

Abstract

The Atlantic Rainforest is a biodiversity hotspot with high endemism. Botanical sampling in its interior mountains is limited, affecting knowledge of locally endemic or undescribed species. The aim was to investigate the presence and distribution of rare and threatened species in different Atlantic Rainforest fragments. Atlantic Rainforest of Minas Gerais state, Brazilian southeastern. We used multi-level forest inventory data from 137 plots across nine Semideciduous Seasonal Forest fragments, sampled 1-9 times over 30 years. We selected species with ≤ 60 previous records, associating coordinates to plot distribution maps. We analyzed species' distribution in the biodiversity repositories SpeciesLink, JABOT, and GBIF to avoid omitting exclusive records on any of these platforms. We documented 17 new records and listed 243 previous records of 12 rare species in eight families. These species are endemic to the Atlantic Rainforest, with most showing some level of threat. The new records expanded species' occurrence zones, and Homalolepis insignis and Rhodostemonodaphne anomala were documented for the first time in Minas Gerais state, highlighting that collection in under-sampled regions is essential for improving species knowledge and reducing sampling bias. The previous record numbers varied across species, with misidentifications causing inconsistencies in occurrence records, particularly for Didymopanax longipetiolatus. Physical and digital collections need review to correct identification errors, synonyms used improperly, and imprecise coordinates. This information is crucial for identifying priority areas for conservation, especially rare and threatened species. A concerning lack of synchronization between scientific publications, biodiversity repositories, and government organizations may compromise policy development for environmental management and resource allocation to protect vulnerable areas.

Keywords: IUCN conservation status; Myrtaceae; Seasonal Semideciduous Forest; conservation polices; digital biodiversity repositories; endemic flora; herbarium collections; species distribution.