keys to the vascular plants of east texas - Botanical Research ...

OPHIOGLOSSUM/OPHIOGLOSSACEAE
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Ophioglossum crotalophoroides Walter, (from Greek: krotalon, a rattle, and -oides, like or resembling,
due to the resemblance of the sporangial clusters to rattles or castanets), BULBOUS
ADDER’S-TONGUE, DWARF ADDER’S-TONGUE FERN. Plant usually to only 15 cm tall; stems (� subterranean)
globose-bulbose, 3–12 mm diam., nut-like or pea-sized; leaves (blade portion and fertile
portion combined) 2 per stem; blade portion to 3.5 cm long and 2.5 cm wide, usually
smaller, pale green; fertile stalk 1–5 times as long as blade portion; sporangia 4–8(–12) on each
side of fertile stalk. Usually in moist sand, ditches, lawns, cemeteries, areas where grass is short;
Pineywoods and Post Oak Savannah w to Fannin (BRIT), Bastrop, McLennan, Milam (BAYLU),
and Hunt (Turner et al. 2003) cos. and from lawn in Dallas Co. (TAMU); also Bosque Co.
(BAYLU) in Cross Timbers and Prairies, n Gulf Prairies and Marshes, and e Edwards Plateau; se
U.S. from NC s to FL w to OK and TX. Leaves appearing late winter and early spring, sometimes
later in season after heavy rains; usually sporulating Mar–May. The globose-bulbose stem is
unique among TX members of the genus. According to Thomas (1979), “This species is probably
the most common fern in East Texas and is found abundantly in early spring in almost every
sandy area where grass is short, such as school lawns and cemeteries.”
Ophioglossum engelmannii Prantl, (for George Engelmann, 1809–1884, German-born American
botanist), ENGELMANN’S ADDER’S-TONGUE, LIMESTONE ADDER’S-TONGUE. Plant to 25 cm tall; leaves
(blade portion and fertile portion combined) 1–2 per stem; blade portion to 10 cm long and 4.5
cm wide, commonly folded when alive, when dried uniformly pale green without pale central
band, dull; fertile stalk 1.3–2.5 times as long as blade portion; sporangia 20–40 on each side of
fertile stalk. Usually in thin black soils on limestone, wooded rocky slopes; Pineywoods and
Gulf Prairies and Marshes w to West Cross Timbers, also e Edwards Plateau and Deaf Smith Co.
in the Panhandle (Floyd Waller collection—J. Stanford, pers. comm.); e U.S. from PA s to FL w to
NE, AR, and TX and in the sw to NM and AZ. Leaves appearing from early to late spring, often
with a second flush of leaves following summer rains; usually sporulating Dec–Jun. m/292
Ophioglossum nudicaule L., (naked stem), SLENDER ADDER’S-TONGUE, LEAST ADDER’S-TONGUE.
Plant to ca. 12 cm tall; leaves (blade portion and fertile portion combined) commonly 2–3 per
stem; blade portion to 4.5 cm long and 1.7 cm wide but often very small (� 4 mm long and 3
mm wide), green, dull, the largest with pale central band; fertile stalk 2–6 times as long as blade
portion; sporangia 5–12 on each side of fertile stalk. Disturbed places (e.g., cemeteries, mowed
areas around motels), ditches, grassy slopes, wet meadows, damp depressions in pinelands,
moist open woods, bog margins; Shelby Co. (Thomas 27493, 16 Feb 1972—BRIT) near the LA
border, also Hardin, Orange, San Augustine (Thomas 1979), and San Jacinto (E. Keith, pers.
comm., BAYLU) cos. in the Pineywoods; se U.S. from VA s to FL w to OK and TX. Leaves appearing
in late winter and early spring, sometimes with a second flush of leaves after heavy rains;
usually sporulating Dec–Jun. [O. dendroneuron E.P. St. John, O. ellipticum Hook. & Grev., O.
mononeuron E.P. St. John, O. nudicaule var. minus Clausen, O. nudicaule var. tenerum (Mett. ex
Prantl) Clausen, O. tenerum Mett. ex Prantl] According to Wagner et al. (1984), this is the most
variable and taxonomically confused species of Ophioglossum in the se U.S., with a complete
transition series from small- to large-leaved (previously called O. ellipticum) forms.
Ophioglossum petiolatum Hook., (with a petiole or leaf stalk), STALKED ADDER’S-TONGUE, LONG-
STEM ADDER’S-TONGUE. Plant to ca. 21 cm tall; leaves (blade portion and fertile portion combined)
commonly 2–3 per stem; blade portion to 1.5–6 cm long and 0.6–3 cm wide, apically
acute, gray-green, dull, flat or nearly so when alive; fertile stalk 0.8–7 times as long as blade portion;
sporangia to 30 on each side of fertile stalk. Wet woods, disturbed places (e.g., cemeteries,
mowed areas), ditches, moist meadows, depressions; Hardin, Orange (BRIT), Jasper, and Liberty
(Thomas 1979; Thomas et al. 1987) cos. in the Pineywoods; also Jefferson Co. (Thomas 1979;
Turner et al. 2003) in the n Gulf Prairies and Marshes; naturalized se U.S. from NC s to FL w to
OK and TX. Leaves appearing during wet periods; usually sporulating Feb–Jun. Native of West
Indies, Mexico, n South America, Asia (including India), and Pacific Islands. Wagner and