Ophioglossum crotalophoroides
Ophioglossum crotalophoroides Walter
(from Greek: krotalon, a rattle, phoros, bearer, and -oides, like or resembling, meaning “like a rattle bearer”, due to the resemblance of the sporangial clusters to the rattles of a rattlesnake—Thieret 1980)
Local names: bulbous adder’s-tongue, dwarf adder’s-tongue fern
Plant usually to only 15 cm tall; stems (more or less subterranean) globose-bulbose, 3–12 mm diam., nut-like or pea-sized; leaves (blade portion and fertile portion combined) 1–3 (often 2) per stem; blade portion to 3.5 cm long and 2.5 cm wide, usually smaller, pale green, spreading or nearly flat on ground; fertile stalk 1–5 times as long as blade portion; sporangia 4–8(–12) on each side of fertile stalk. Usually observed in moist sand, ditches, lawns, cemeteries, areas where grass is short; Pineywoods and Post Oak Savannah w to Fannin (J.&C. Taylor 4832, BRIT), Bastrop (BAYLU), Milam (TEX-LL), McLennan (W.C. Holmes 7613, 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 in Gillespie (O’Kennon 10456, Bexar Mt., BRIT), Burnet (TEX-LL), and Llano (Turner et al. 2003) cos.; se U.S. from NC s to FL w to OK and TX; also Mexico to South America and West Indies. 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 and Wagner and Wagner (1993) noted the species “is very remarkable morphologically for its highly modified stem and threadlike nonproliferous roots.” 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.” Thomas et al. (1981) noted that this species “will remain dormant during unusually dry springs.” Nelson (2000) commented that, the “bulbous, rounded, field-pea-size stem distinguishes this species from other members of the genus.” The shape and size of the blade portion of the leaf can vary significantly depending on soil texture and depth (Thieret 1980). Seigler (1977) reported that in the Central Mineral Region it occurs “in shallow pools and depressions in granite and sandstones.”