California Adderstongue

Ophioglossum californicum differs from the Old World species O . lusitanicum in that O . lusitanicum has a narrowly linear to linear-oblanceolate trophophore that is 1/4 to 1/2 as wide as long; O . lusitanicum also has a much simpler venation and usually lacks an apiculum.

Roots to 16 per plant, pale brown, 0.5-1 mm diam., producing proliferations. Stem upright, to 1.6 cm, 5mm diam., commonly 2 leaves per stem. Trophophore stalk 0-1.8cm, to 2.5 times length of trophophore blade. Trophophore blade erect to spreading, commonly ± folded when alive, green, dull, without pale central band when dried, to 4.3 × 1 cm (rarely 0.4 × 0.3 mm), herbaceous, thick, gradually tapering to base, apex attenuate; venation complex-reticulate, with numerous parallel narrow areoles, each with 1-several included veinlets. Sporophores arising near ground level, 1-2.5 times length of trophophore; sporangial clusters 8-15 × 1-3 mm, with 8-15 pairs of sporangia, apiculum 0.3-1 mm.

Calif.; Mexico.

Leaves appearing in late winter and early spring; apparently absent during dry years. Open grassy fields and prairies; 50-300m.

Ophioglossum lusitanicum Linnaeus subsp. californicum (Prantl) R. T. Clausen

Ophioglossum californicum Prantl, Ber. Deuts. Bot
Ges. 1 : 351. 1883.
Plant 2.5-11.5 cm. high; rhizome stout, cylindric, 2-17 mm. long, 2-3 mm. thick; roots usually numerous, fibrous and somewhat fleshy, persistent, 0.5-1 mm. thick ; leaves usually 2 (1-3) ; commonstalk 0.3-2.6 cm. long, hypogean ; lamina folded, sessile or shortstalked, usually upwardly inclined, elliptic or oval, acute, often apiculate, 1.5-4.2 cm. long, 0.3-0.9 cm. broad, the basal veins 3-7, the median vein about equal to the others, free except for secondary interconnecting veinlets, the areolae mostly parallel to the median vein, narrow, simple or with a few included veinlets ; sporophyl 1.4-9 cm. long, the spike 6.5-20 mm. long, 1-3 mm. thick, apiculate; sporangia 9-17-jugate; spores finely pitted, .045-. 05 mm. in diameter, finely pitted when young, later verrucose.
Type locality : San Diego, California.
Distribution : Southern California to Mexico.

Ophioglossum californicum, known by the common name California adder's tongue, is an uncommon species of fern in the family Ophioglossaceae.

The fern is native to California, and Baja California in Northwestern Mexico. It is found in the San Joaquin Valley, Sierra Nevada foothills, and along the central and southern coast regions. Habitats include moist areas, such as wet pastures and vernal pools, coastal grasslands, and coastal/montane/interior chaparral micro-habitats. It becomes very rare in dry years.