Update on the status of orchids of Long Island, New York1

The orchids of Long Island have been studied by local botanists for almost 200 years, making it one of the longest, continuous floristic studies in the New World. The island's orchid flora comprises 16 genera and 39 species, plus two hybrids and one additional infraspecific taxon; all but one (Epipactis helleborine) are native. Platanthera is the largest genus with 10 species, followed by Spiranthes with seven species. Twenty of the 42 orchid taxa recorded from Long Island are considered extirpated; of the 20, seven are orchids with northern affinities, suggesting a potential role of climate change. Updated distribution maps are presented for all taxa as well as discussion of recent changes in population dynamics, potential causes of declines in frequency, conservation efforts, and an extensive list of references. Platanthera pallida is treated as a distinct species, possessing unique morphological features distinct from P. cristata, endemic to the Montauk Peninsula of eastern Long Island.