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bulbous Adder's-tongue

longstem Adder's-tongue, stalk Adder's-tongue


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

dark brown, to 8 per plant, 0.8-1.3 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, 0.3-1 cm, 1.5-2.5mm diam., 2-3 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 0-3mm, 0-0.1 times length of blade.;

trophophore blade erect to spreading, usually plane or nearly so when alive, gray-green, dull, ovate to trowel-shaped, to 6 × 3cm, fleshy, cuneate to truncate to nearly cordate at base, contracted gradually to acute apex, apiculum mostly absent;

venation coarse, reticulate, areoles large with few free or anastomosing 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 at ground level, 0.8-7 times length of trophophore;

sporangial clusters to 4 × 0.35 cm, with up to 30 pairs of sporangia, apiculum 0.3-1.2 mm.

Ophioglossum crotalophoroides

Ophioglossum petiolatum

Phenology Leaves appearing mainly in late winter and early spring, sometimes also appearing later in season after heavy rains. Leaves appearing during wet periods.
Habitat Second-growth fields, vacant lots, roadside ditches, and lawns Plants sometimes weedy in lawns, ditches, and around buildings
Elevation 0-100 m (0-300 ft) 0-90m (0-300ft)
from FNA
AL; AR; FL; GA; LA; MO; MS; NC; SC; TX; Mexico; Central America; South America; widespread in tropical highlands; West Indies
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; FL; GA; LA; MO; MS; NC; OK; SC; TX; VA; Mexico; West Indies; n South America; Asia; Pacific Islands [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]

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 petiolatum grows readily in pots, making it suitable for botany instruction. Earliest records in North America date from 1900 to 1930, suggesting that it is probably introduced.

(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. californicum, O. crotalophoroides, O. engelmannii, O. nudicaule, O. pusillum, O. vulgatum
Name authority Walter: Fl. Carol. 256. (1788) Hooker: Exot. Fl. 1: 56. (1823)
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