Lycopodiaceae belongs to the Lycopsida, which autapomorphy is the presence of microphyllous leaves. It was studied 10 species, and seven are endemic to Brazil: the terrestrials Huperzia christii (Silveira) Holub, H. friburgensis (Nessel) B. Øllg., H. hemleri (Nessel) B. Øllg., H. intermedia Trevis., H. reflexa (Lam.) Trevis. and H. treitubensis (Silveira) B. Øllg.; the epiphytics H. fontinaloides (Spring) Trevis., H. heterocarpon (Fée) Holub, H. hexasticha B. Øllg. & P.G. Windisch and H. quadrifariata (Bory) Rothm. The anatomical features found that are probably adaptive to a water deficient environment are the presence of epidermal cells with sinuous anticlinal walls, invaginations in the inner side of external periclinal wall of the epidermal cells and amphiestomatic leaves. The analysed species were separated in two groups, corroborating existing classifications. The two groups were defined on the basis of the following characters: phyllotaxis helical or opposite, leaf position in relation to the stem, if reflexed or adpressed, and the number of sporangia cell layers, if three or four. An identification key was elaborated.
Huperzia; leaf; Lycopodiaceae; plant anatomy; Pteridophyta
