Abstract Detail

Biodiversity at the brink: leveraging herbaria for conservation!

Identifying and preventing plant extinction events: The critical role of herbaria.

Herbaria play a fundamental role in our understanding of plant extinctions. Of the 65 plant taxa (51 species, 14 infraspecies) believed extinct from the continental United States and Canada, 20 are known only from the type material and 4 are “dark” extinction events. A dark extinction is the extinction of an undescribed or unrecognized species. If not for the physical specimens, these species would have remained unrecognized and undocumented extinction events. Of these 4 dark extinctions, the most recent is Marshallia grandiflora which was only recognized as distinct and extinct in 2020, having been last collected in 1919. Overcollection for herbarium vouchers has most likely caused the extinction of 3 single-site endemic taxa. One example of this overcollection is the 56 sheets of material of the now extinct Juncus pervetus. Single-site endemics represent 64% of all known plant extinctions in the USA and Canada. Currently, no method exists to identify single-site endemics, despite their disproportionate impact on biodiversity conservation. I will present preliminary data on plants of one known occurrence (OKO), which includes single-site endemics. These OKO plants need immediate in situ and ex situ conservation attention to prevent extinctions. These species are often so rare that there are few herbarium vouchers. This creates challenges for understating the taxonomic merit of these OKO species and the accurate identification of new populations.

1 - NatureServe, Botany, 2550 South Clark Street, Arlington, VA, 22202

Keywords:
extinction
conservation
single-site endemics
in situ
ex situ.

Presentation Type: Special Sessions
Number: SS002
Abstract ID:233
Candidate for Awards:None