Nexus-formatted text file of ISSR band presence/absence for 75 loci in Corallorhiza bentleyi

Mycoheterotrophic plants derive most or all carbon and nutrients from
fungal partners and represent poorly understood components of forest
biodiversity. Many are rare or endangered yet can be ecological indicators
of forest ecosystem function due to their often highly specific fungal
host requirements. One such species is the IUCN red-listed (‘vulnerable’),
fully mycoheterotrophic orchid, Corallorhiza bentleyi. This recently
described species is among the rarest plants in Appalachia, known from
five counties in Virginia and West Virginia, USA. The species has a
restricted range, small population size, and is self-pollinating. Here, an
integrative approach was taken in conservation genetic assessment of C.
bentleyi using floral morphometrics, simple-sequence repeats, and fungal
host DNA to characterize variation within and among sampling localities.
Morphology reveals some differentiation among individuals from six
sampling localities. Surprisingly, most genetic variation is found within
localities, contrary to the expectation for a selfing species. Fungal host
DNA reveals extreme specificity upon a few genotypes of a single
ectomycorrhizal host species, Tomentella fuscocinerea, across all
localities. The conservation implications of morphological, genetic, and
symbiotic diversity in this vulnerable species are discussed, and
additional assessment of conservation status is recommended based on: an
obligate reproductive mode of selfing, preventing benefits of outcrossing
among genetically non-identical individuals; extreme host specificity,
severely restricting niche space; and highly fragmented habitat under
threat from anthropogenic disturbance. This study underscores the
importance of integrative conservation assessment, analyzing multiple data
sources, and reveals patterns not readily apparent from census-based
assessments alone.