Xyris laxifolia
Content
Description
Robust, smooth perennial, 50-150 cm high, bases soft, usually reddish or purple. Leaves erect or in a fan, 40-70 cm, sheath entire eligulate, blade flattened, 10-20 mm wide, margins thin or slightly thickened, smooth. Scapes distally terete to oval or elliptic, mostly 2-edged and ribless, smooth; spikes ovoid to cylindric, 3-3.5 cm, green-brown, bracts in a tight spiral, convex with evident dorsal area, empty ones several, grading larger into the flowering ones, these ovate to obovate or suborbicular, ecarinate, 7-10 mm, narrowly rounded at apex, entire. Lateral sepals free, equilateral, curved, 5-6.5 mm, keel wide, lacerate or lacero-fimbriate from about middle to tip; petals broadly obovate, ca. 5 mm; staminodes bearded; anthers ca. 2.5 mm. Capsule 5.5-6.5 mm, placentation parietal; seeds ellipsoid-fusiform, 0.7-0.9 mm, slightly to evidently farinose, rarely translucent.
Distribution
Andes present, Mesoamerica except at higher elevations present, South America present, southern Mexico present
Through most of South America east of the Andes and through Mesoamerica except at higher elevations and N to southern Mexico,
Notes
Difficulties in distinguishing this from X. jupicai are discussed under that species. Troubles with typification result from mixtures of this and other species, particularly X. jupicai on sheets of historical material.
In Mexico (Tobasco, Veracruz) and in the Southeastern United States, there is a variety which was first described by A. W. Chapman (1860) asX. iridifolia . This is treated in my ongoing work with Xyris of North America as X. laxifolia var. iridifolia (Chapm.) Kral , a plant similar to the type variety in pigmentation, general dimensions, sepals, petals and seed, but differing consistently in having broader, more ancipital, scapes and more often cylindric spikes.
In Mexico (Tobasco, Veracruz) and in the Southeastern United States, there is a variety which was first described by A. W. Chapman (1860) as