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Huperzia selago subsp. appressa (Bach.Pyl. ex Desv.) D.Löve
Huperzia selago var. appressa (Bach.Pyl. ex Desv.) Ching
Lycopodium appressum (Bach.Pyl. ex Desv.) Petrov
Lycopodium selago subsp. appressum (Bach.Pyl. ex Desv.) Hultén
Lycopodium selago f. appressum (Bach.Pyl. ex Desv.) Gelert
Lycopodium selago var. appressum Bach.Pyl. ex Desv.
Lycopodium selago subsp. arcticum Tolm.
Urostachys selago var. appressus (Bach.Pyl. ex Desv.) Herter ex Nessel
Huperzia appressa, commonly known as Appalachian firmoss, is a non-flowering species of plant in the family Lycopodiaceae. It has been reported from the United States, Canada, China, Russia, and several European countries. It is a terrestrial plant up to 10 cm tall, with dichotomously branched stems.