16. Ruellia tubiflora H. B. K.
Ruellia tubiflora H. B. K. Nov. Gen. & Sp. 2: 241. 1817. Type collected on shaded bank of Río Magdalena near Honda; Tolima, Colombia. The specific name alludes to the long tubular flowers. Scorodoxylum hartwegianum Nees in Benth. Pl. Hartw. 236. 1846. Type collected in a shady place near the village of Guaduas, Bogotá, Colombia, by Hartweg.
Ruellia purdieana Hook. Bot. Mag. Curtis 73: pl. 4298. 1847. Named in honor of Purdie and based on cultivated material. The type may possibly have been grown from seed collected by Purdie in the Santa Marta region of Colombia.
Arrhostoxylum hartwegianum Nees in DC. Prodr. 11: 209. 1847. A new combination based on Hartweg's specimen from Guadas.
Ruellia stuebelii Lindau in Bot. Jahrb. Engler 21: 377. 1896. Type collected in the vicinity of Honda by Stuebel, No. 68a.
Suffrutescent herbs up to 1 meter high; stems ascending, subquad- rangular, glabrous, or puberulous at tips and nodes, the upper portions bearing minute glandular scales; leaf blades oblong-elliptic, 6 to 24 cm. long, 6 to 9 cm. wide, more or less abruptly acuminate at apex (the tip itself blunt), narrowed at base and decurrent on the petiole, entire, undulate or shallowly crenate, glabrous, both surfaces bearing minute semitranslucent reddish glands, or, in absence of these, minute pits, the glands and pits more conspicuous on the lower surface than on the upper, the cystoliths (upper surface) numerous, slender, minute, the costa and lateral veins (7 to 9 pairs) fairly prominent; petioles 1 to 3 cm. long, glabrous or puberulous; inflorescence a short terminal spike subtended by leafy bracts 2 to 5 cm, long and 1.5 to 2 cm. wide, the rachis conelike, 5 to 12 mm. long, bearing 4 rows of conspicuous scars after the falling of bracts and flowers; bractlets triangular, 1 to 2 mm. long; pedicels 2 to 3 mm. long; calyx up to 15 mm. long, gland- dotted, the segments lanceolate, 3 to 14 mm. long, 1 to 2 mm. wide, glabrous or puberulous; corolla crimson, lilac, or red, sparingly puberulous, gland-dotted, about 4 cm. long, the tube infundibular, curved, 1 to 1.5 cm. broad at throat, the limb about 3 cm. broad, the lobes oval or suborbicular, 1 cm. long or more, spreading; anthers slightly exserted, sagittate, 3.5 mm. long; capsule clavate, 15 mm. long, about 8 mm. broad, puberulous or glabrate, gland-dotted, the solid basal portion 3 to 4 mm. long and broad, the retinacula curved, slender, 5 mm, long, seeds 8 or more, flat, orbicular, 5 mm. in diameter, 1 mm. thick, appressed-pilose when dry, mucilaginous-pilose when moistened.
Ruellia tubiflora is extremely variable in the color and size of the corolla, in the type and abundance of the pubescence, and in the rela- tive size, shape, and texture of the leaf blades. On the other hand, it is very constant in the type of inflorescence, the presence of the minute glandular scales, dots, or pits on various parts of the plant, especially the leaf blades, calyx, bracts, and capsules, and in the presence of the large leaflike bracts supporting the flower cluster. The typical form is glabrous or more or less puberulous and produces large purple or reddish flowers. White-flowered plants from Costa Rica were called R. tetrastichantha by Lindau. This name is often applied to the white-flowered plants of Colombia as well as to those with purple- throated corollas. Still other plants produce yellow flowers (Costa Rica), others, small white or purple ones, and one Colombian plant, although producing large white flowers, is strongly hirsute. These variations are here given varietal or form status.
The leaf blades of some of the specimens examined (Cuatrecasas 10529) are thin, drying green, but those of others (Ariste-Joseph A973) are thickish and turn blackish on drying. This variation might possibly be due to a difference in habitat, the thin-leafed plants grow- ing in shaded regions and the thick-leafed ones in more open situations. Damp forests or thickets at lower elevations (400 to 450 meters). Panama, Colombia.
BOLÍVAR: La Popa, vicinity of Cartagena, Billberg s. n. (S).
HUILA: Río Saldaña to Natagaima, Rusby & Pennell 250 (GH, NY). META: Susumoco, vicinity of Villavicencio, Triana s. n. (Col).
TOLIMA: Armero, Cuatrecasas 10529 (US), Honda, Bro. Ariste-Joseph A973 (US). Río Seco, above Honda, Holton 282 (GH); Triana s.n. (Col).