Selaginella ×neomexicana

Selaginella ×neomexicana Maxon
(of New Mexico, the species occurring in NM as well as AZ and TX)

Local names: New Mexico spike-moss

Plants forming clumps, the aerial stems erect to ascending (can be pendant in large plants when on a nearly vertical surface—see photo), radially symmetrical, with rhizophores mainly on lower . of erect aerial stems; underground (rhizomatous) stems present; rhizomes and aerial stems often with a bud-like arrested branch near base; leaves of aerial stems essentially of 1 kind, appressed, linear-lanceolate, 1.9–2.7 mm long, marginally long-ciliate at base but merely minutely denticulate toward apex, apically keeled, with whitish bristle; strobili solitary, quadrangular, usually 1–3 cm long; sporophylls apically keeled, bristled. On rocks of canyons, often on granite: rare in the Trans-Pecos and adjacent Val Verde Co.—in the Franklin Mts., El Paso Co. (e.g., Correll 15025, 15035, TEX-LL), and Chisos Mts. and Sunny Glen, Brewster Co. (P. Zelazny 93, SRSC; Yarborough & Powell 2002), and reported for Presidio and Val Verde cos. (Correll 1956; Yarborough & Powell 2002) (we have been unable to relocate the Val Verde Co. collections cited by Correll; therefore the location for that county is mapped in the sw part of Val Verde w of the Pecos River since Correll described the species as being “rare in the Trans-Pecos region of west Texas”); endemic to AZ, NM, and TX. Spores lacking or malformed. This taxon, which is clearly similar in many ways to S. rupincola (e.g., long, spreading, marginal leaf cilia, rhizomatous underground stems) has long been treated as a hybrid (e.g., Tryon 1955; Velaspino 1993); megaspores and megasporangia are lacking and the microsporangia are misshapen. It has been proposed that possible parents are S. rupincola and S. mutica (Tryon 1955) (like S. ×neomexicana, the sympatric S. mutica has strongly keeled leaf apices). Velaspino (1993) suggested S. rupincola × S. underwoodii (also sympatric) as another possible parentage or even that ×neomexicana is an asexual race of S. rupincola. Further research is clearly needed to clarify its relationships. Given its very limited range (endemic to extreme s AZ, NM, and TX) and rareness, we consider this taxon to be of conservation concern.

: Back to List :