Shoots erect, indeterminate, 14--20(--100) cm, becoming long-decumbent, with long, trailing, senescent portion turning brown; juvenile and mature portions similar with strong annual constrictions due to formation of winter bud; juvenile growth erect. Leaves spreading to reflexed, dark green, lustrous; largest leaves narrowly obovate, leaves broadest at or above middle, 7--11 mm, margins papillate, teeth 1--8, irregular, large; smallest leaves (at annual constrictions) narrowly lanceolate, 3--6 mm; stomates on abaxial surface only. Gemmiferous branchlets produced in 1 pseudowhorl at end of each annual growth cycle; gemmae 4--6 X 3--6 mm, lateral leaves 1.5--2.5 mm wide, broadly obtuse with distinct mucro. Spores 23--29 µm. 2 n = 134. Terrestrial in shaded conifer forests and mixed hardwoods, rarely on rock on shady mossy acidic sandstone; 0--1800 m; St. Pierre and Miquelon; Man., N.B., Nfld., N.S., Ont., P.E.I., Que.; Ala., Ark., Conn., Del., Ga., Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Mo., N.H., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis. Huperzia × bartleyi (Cusick) Kartesz & Gandhi, a sterile hybrid between H . lucidula and H . porophila , occurs throughout the range of H . porophila and is discussed under that species. Huperzia × buttersii (Abbe) Kartesz & Gandhi is a hybrid between H. lucidula and H. selago .