Mickel, John T. & Smith, Alan R. 2004. The pteridophytes of Mexico. Mem. New York Bot. Gard. 88: 1-1054.
Selaginellaceae
Species Description - Stems long-creeping, rooting at intervals of 10–15 cm, forming very loose mats, 0.4–0.6 mm diam., erect stems 5–8 cm tall produced at intervals of 1–3 cm, apices curling when dry, graytan, not articulate, not flagelliform, not stoloniferous, 2–3 times branched; leaves of two kinds (anisophyllous) on erect stems, monomorphic on arching stems, buff, coriaceous, tightly appressed to wiry, brownish stems that are often visible between the leaves, leaves on the erect portion grading to grayish green distally, spreading, tightly imbricate, neither stems nor leaf bases visible; lateral and median leaves similar in size, shape, and texture, ovate, 1–1.5 mm long, apices rounded or cuspidate, peltately attached, each with downward-pointing, erose auricle, margins otherwise entire, acroscopic margins thin, subscarious; axillary leaves oblanceolate, apices rounded to cuspidate, peltately attached, with ciliate to erose auricles; strobili quadrangular, 2–5 mm long; sporophylls monomorphic; megaspores white to cream, with low, unequal, sparingly anastomosing ridges; microspores orange to orange-tan, with heavy broad ridges.
Lectotype (chosen by Alston, 1952: 240, and again by Mickel 1992: 427, neither author fixing the location of the lectotype. We here designate the specimen at B as lectotype). Mexico. San Luis Potosi´: San Rafael Mountains, 1879 (not 1878, as in publ.), Schaffner 8 (B!-image seen; isolectotypes BM, NY!, US!).
Selaginella schaffneri is distinguished by the peltate attachment of leaves and sporophylls, all of which have branched veins that occasionally anastomose. As pointed out by Wagner et al. (1982), leaves with complex venation are a radical departure from the usual condition (a single, unbranched vein) in the entire lycopod evolutionary line (including also Isoe¨tes). Unfortunately, because of the thick and opaque nature of the leaves, the complex veins are not visible unless the leaves are cleared and the vascular tissue stained. The name S. saccharata has been mistakenly applied to plants of S. schaffneri, but that name is a synonym of S. delicatissima
Mexico North America|