2. Huperzia haleakalae (Brackenridge) Holub, Folia Geobot. Phytotax. 20: 73. 1985.
Lycopodium haleakalae Brackenridge in Wilkes, U.S. Expl. Exped. 16: 321. 1854; L. selago Linnaeus var. haleakalae (Brackenridge) Warburg; Urostachys haleakalae (Brackenridge) Herter ex Nessel
Shoots erect, indeterminate, 8--11 cm, short- to long-decumbent, 3--8 cm; leaves in mature portion smaller than in juvenile portion; annual constrictions absent; juvenile growth erect. Leaves spreading-ascending to appressed, yellow-green to yellow-brown, greener at stem tip (top 1 cm), lustrous (as if covered with clear yellow varnish); leaves in juvenile portion lanceolate, 4.5--6(--7) mm, apex acute; leaves in mature portion ovate, 3--4 mm, apex acute; margins entire, with scattered papillae; stomates present on both surfaces, numerous (38--84 per 1/2 leaf) on adaxial surface. Gemmiferous branchlets produced throughout mature portion of shoot; gemmae 3--4 X 3.5 mm, lateral leaves 1.5--2 mm wide, broadly acute to obtuse. Spores 31--41 µm.
Terrestrial in exposed, moist meadows and mossy heaths in alpine and subalpine zones; (160--)1300--1700(--3600) m; Alta., B.C., Yukon; Alaska, Colo., Mont., Wash., Wyo.; Asia in Siberia; Pacific Islands in Hawaii.
Huperzia haleakalae has been found in Hawaii in Haleakala Crater, on Maui, at 2300 meters, but it is extremely rare or possibly extinct there.