Vittaria appalachiana: A Name for the "Appalachian Gametophyte"

Abstract

the presence of gametophytes of Hymenophyllum in the gorges of the Southern Mountains up to 40 km from the single locality for H. tunbrigense (L.) Smith in Pickens Co., South Carolina. In each of these cases, the gametophytes have the characteristic of producing gemmae by which they maintain local populations vegetatively and independently of the sporophyte generation. Species of Vittaria, the shoestring ferns, also have gemma-producing gametophytes. In the continental United States, Vittaria is represented by three species. In peninsular Florida, V. lineata (L.) Smith is common on trunks of cabbage palms in both gametophyte and sporophyte stages. Here gametophytes produce the gemmae characteristic of the genus, but also produce sporophytes in a normal sexual life cycle (Farrar, 1974, 1978). Gametophytes of the common Central American species, V. graminifolia Kaulf., have been collected from bases of beech trees in southern Alabama (Farrar & Landry, 1987). In the Mountains and Plateau regions of the eastern United States, a third species of Vittaria is represented by the gametophyte stage only. It is distinct from the gametophytes of the other two species. It is a common and conspicuous, though often unrecognized, component of the vegetation of cool, moist, heavily shaded outcroppings of non-calcareous rock. A detailed description of these plants and their habitat has been presented by Farrar (1978) along with a discussion of unsuccessful attempts by Farrar and others to induce these plants to produce normal sporophytes in culture. It is this species, commonly known as the Appalachian Gametophyte or Appalachian Vittaria Gametophyte, for which we propose the new Latin binomial, Vittaria appalachiana.