Selaginella apoda (L.) Spring

  • Authority

    Mickel, John T. & Smith, Alan R. 2004. The pteridophytes of Mexico. Mem. New York Bot. Gard. 88: 1-1054.

  • Family

    Selaginellaceae

  • Scientific Name

    Selaginella apoda (L.) Spring

  • Description

    Species Description - Stems prostrate to short-creeping, forming rather loose or clustered mats 3–7 cm long, 0.3–0.5 mm diam., greenish to stramineous, not articulate, not flagelliform, not stoloniferous, sparsely branched, the branches mostly simple or 1-forked; rhizophores borne throughout stem length or restricted to proximal 1/3, less than 0.1 mm diam.; leaves of two kinds (anisophyllous) throughout; lateral leaves ovate to ovate-lanceolate, 1.4–2.3 x 0.8–1.4 mm, bases rounded, margins green or with 1 row of hyaline cells, denticulate, apices acute; median leaves lanceolate, surfaces glabrous, 1–1.6 x 0.4–0.7 mm, bases rounded, margins sparingly denticulate or subentire, apices acuminate to longacuminate; axillary leaves similar to lateral ones, exauriculate; strobili lax and dorsiventral, 1–2 cm long; sporophylls subdimorphic, dorsal ones spreading, ventral ones ascending; megaspores pale yellow to bone-white, reticulate, 330–390 µm diam.; microspores orange, rugulose-reticulate to verruculose, 25–30 µm diam.

  • Discussion

    Lycopodium apodum L., Sp. Pl. 2: 1105. 1753. Type. U.S.A. “Carolina, Virginia, Pensylvania,” Kalm s.n. (LINN 1257.27).

    Selaginella apoda is the central component of a taxonomically difficult species complex of the eastern and southeastern United States. Its closest relative is S. eclipesW. R. Buck. It is also related to S. ludoviciana (A. Braun) A. Braun, from which it can be distinguished by its green or less often narrowly hyaline leaf margins, stomata scattered throughout the leaves, tendency to form rather short mats of prostrate or creeping stems, and rugulose-reticulate to verruculose microspores. Selaginella ludoviciana has lateral leaves with hyaline margins 3–5 cells wide, stomata restricted to the midrib region, long-creeping to ascending stems, and rather smooth microspores.

  • Distribution

    Terrestrial in swamps, meadows, marshes, pastures, damp lawns, shaded slopes, light woods, and stream banks, in basic to acidic soil conditions; 1700–2700 m. E USA; Mexico; Guat.

    Mexico North America| Guatemala Central America| United States of America North America|