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bulbous Adder's-tongue

California Adder's-tongue


to 20 per plant, blackish, usually extremely narrow, often almost hairlike, less than 0.1 mm diam., proliferations not reported.

to 16 per plant, pale brown, 0.5-1 mm diam., producing proliferations.


spheric, 3-12 mm diam., succulent, cormlike with perforation at apex, apical meristem located at bottom of cavity through which leaves emerge at top, leaves 2 per stem.

upright, to 1.6 cm, 5mm diam., commonly 2 leaves per stem.


stalk to 0.6cm, 0.1-0.2 times as long as trophophore blade.;

trophophore blade lying nearly flat on ground, not folded longitudinally, pale green throughout, deltate to cordate, to 3 × 2 cm, contracted abruptly at truncate to cordate base, apex with apiculum.

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.


coarsely reticulate with included veinlets.


arising at ground level, 1-5 times as long as trophophore;

sporangial clusters usually short, less than 1 cm, 2-3 mm wide, with 3-8 pairs of sporangia, apiculum to 1.5 mm.

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.

Ophioglossum crotalophoroides

Ophioglossum californicum

Phenology Leaves appearing mainly in late winter and early spring, sometimes also appearing later in season after heavy rains. Leaves appearing in late winter and early spring; apparently absent during dry years.
Habitat Second-growth fields, vacant lots, roadside ditches, and lawns Open grassy fields and prairies
Elevation 0-100 m (0-300 ft) 50-300 m (200-1000 ft)
from FNA
AL; AR; FL; GA; LA; MO; MS; NC; SC; TX; Mexico; Central America; South America; widespread in tropical highlands; West Indies
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from FNA
CA; Mexico
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Ophioglossum crotalophoroides is very remarkable morphologically for its highly modified stem and threadlike nonproliferous roots. The gametophyte is disclike (M.R. Mesler 1973). It is especially common in lawns and cemeteries in the southeastern United States.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

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.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Ophioglossaceae > Ophioglossum Ophioglossaceae > Ophioglossum
Sibling taxa
O. californicum, O. engelmannii, O. nudicaule, O. petiolatum, O. pusillum, O. vulgatum
O. crotalophoroides, O. engelmannii, O. nudicaule, O. petiolatum, O. pusillum, O. vulgatum
Synonyms O. lusitanicum subsp. californicum
Name authority Walter: Fl. Carol. 256. (1788) Prantl: Ber. Deutsch. Bot. Ges. 1: 355. (1883)
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