Thelypteris ovata
Thelypteris ovata R.P. St. John var. lindheimeri (C. Chr.) A.R. Sm.
(sp.: Latin: ovatus, egg-shaped or ovate; var.: for F.J. Lindheimer, 1801–1879, German-born TX collector)
Local names: Lindheimer’s maiden fern, ovate marsh fern, Lindheimer’s shield fern, San Saba fern
Rhizomes usually long-creeping; petioles straw-colored; leaves monomorphic, sometimes evergreen; leaf blades usually broadest between middle and base, tapered, the lower pinnae reduced (leaf egg-shaped in outline), the basalmost pinnae angled downward, the basal pair of ultimate segments of the middle pinnae often elongate parallel to rachis, the blades glabrous or with minute pubescence above, with scattered hairs along veins, the lower surface with indument of short hairs on veins and blade tissue; basal veins of adjacent ultimate leaf segments not united, reaching margin at or just above sinus between segments, sometimes meeting at the sinus; sori supramedial to submarginal (sori typically closer to leaf margins than in T. kunthii); indusia with pubescence; 2n = 72 (Smith 1993a). Low, moist areas, wet bluffs and ledges, including limestone; mainly Edwards Plateau and Trans-Pecos but east to Bell (S. E. Wolff 3397, BRIT), Bexar, Comal, Hays, Travis (TEX-LL), and Williamson (Turner et al. 2003) cos. near w margin of Blackland Prairie, also Tarrant Co. (J. Quayle s.n. 1996, “possibly escaped from cultivation,” BRIT) in the Cross Timbers and Prairies; in the U.S. known only from TX; also Mexico, Central America, and West Indies in Jamaica. Sporulating May–Nov. [Dryopteris normalis C. Chr. var. lindheimeri C. Chr.] This species has often been confused and lumped (e.g., Correll 1956; Correll & Johnston 1970; Hatch et al. 1990) with Thelypteris kunthii (either as T. kunthii or under the name Dryopteris normalis). Although strikingly similar in overall aspect, the two can be readily distinguished by the characters in the key to species. This is one of 19 pteridophyte species known in the U.S. only from TX (see page 41).