Bushy Spikemoss

Selaginella bigelovii is a member of the series Arenicolae (R. M. Tryon 1955) and is closely related to S . rupincola (see discussion). It may be confused with S . × neomexicana . Selaginella bigelovii , however, always has well-developed megasporangia with most of the megaspores and microspores well formed, whereas S . × neomexicana is a presumed sterile hybrid that does not form megaspores, seldom forms microspores, and usually has most sporangia misshapen (R. M. Tryon 1955). Moreover, S . × neomexicana has not been reported from either California or Baja California.

Plants on rock or terrestrial, forming clumps. Stems radially symmetric, underground (rhizomatous) and aerial, not readily fragmenting, irregularly forked; rhizomatous and aerial stems often with 1 branch arrested, budlike, tips straight; aerial stems erect or occasionally ascending. Rhizophores borne on upperside of stems, restricted to rhizomes and lower 1/3 of aerial stems, 0.3--0.4 mm diam. Leaves dimorphic, not clearly ranked. Rhizomatous stem leaves persistent, tightly appressed, scalelike. Aerial stem leaves appressed, ascending, green, linear-lanceolate to narrowly lanceolate, 2.2--3.8 X 0.29--0.4(--0.75) mm; abaxial ridges present; base abruptly adnate, cordate to almost peltate, pubescent or sometimes glabrous; margins short-ciliate at base, denticulate toward apex, cilia white to transparent or greenish, spreading at base, ascending toward apex, 0.02--0.08 mm; apex keeled, bristled; bristle puberulent, rough, transparent to whitish, 0.23--0.75 mm. Strobili solitary, (0.4--)1--1.5 cm; sporophylls ovate-lanceolate to lanceolate, abaxial ridges not prominent, base glabrous, margins short-ciliate to denticulate, apex bristled. 2 n = 18.

Calif.; Mexico in Baja California.

Exposed rock crevices, cliffs, boulders, sandstone or igneous rock, serpentine, or gravelly soil; 0--2000m.

Selaginella bigelovii is a species of spikemoss known by the common names bushy spikemoss and Bigelow's spikemoss. It is native to California and Baja California, where it grows in rocky places in many different habitat types, from the coastline to the mountains to the deserts. This lycophyte forms clumps of spreading upright to erect stems up to 20 centimeters long with a few short lateral branches. The linear or lance-shaped green leaves are up to 4 millimeters long, including the tiny rigid bristles at their tips. They are flattened to the stem or stick out just a little. The strobili borne at the leaf bases are yellow-orange in color.