Rhodostemonodaphne revolutifolia Madriñán

  • Authority

    Madriñán, Santiago R. 2004. (Lauraceae). Fl. Neotrop. Monogr. 92: 1-102. (Published by NYBG Press)

  • Family

    Lauraceae

  • Scientific Name

    Rhodostemonodaphne revolutifolia Madriñán

  • Type

    Type. French Guiana. Crique Arataye, Nouragues station, 8 Aug 1990 (male fl), Sabatier 3500 (holotype: NY; isotypes: K, MO).

  • Description

    Species Description - Trees: branches basitonic, in axils of cataphylls; twigs terete, 2-5 mm diam.; epidermis black, barely visible due to indument cover; terminal bud plump, ca. 6 x 4 mm; cataphylls persisting on current flush, to 6 mm long; indument pubescent, persisting for at least two flushes, the hairs dense, to 1 mm long, straight to crisped, erect, yellowish. Leaves: petioles pulvinate, 0.5-1.9 cm x 1.2-2.8 mm, terete; blades chartaceous, flat to bullate, narrowly elliptic, 6-18(-22) X 3-7(-19) cm; base acute, 40-60°; apex attenuate, 70-80°, ultimately acuminate for up to 1.3(-1.5) cm; margin revolute; primary vein above slightly raised and rounded, below prominent; secondary veins 3-6(-7) pairs, equidistant, eucamptodromous, above slightly raised, below prominent, diverging at 55-60(-70)°, evenly arching, chordal angle 20-30°, the angle uniform along blade length; tertiary veins above and below slightly raised, random-reticulate; higher-order veins on both sides slightly raised; surface above yellowish brown in younger leaves, olive-green in older leaves, below greenish brown, slightly glaucous, the veins yellowish to brown; indument above absent, the primary and secondary veins tomentose, below pubescent, the hairs dense, to 1 mm long, straight, erect, yellowish, denser on the veins, persisting for at least two flushes. Staminate inflorescences: basitonic, pendulous, peduncles 12-17 cm long, the hypopodia 5-9 cm X 1- 1.2 mm, branch orders 5, the second-order branches 4-5, dispersed, lowest branch to 4.5 cm long, all axes greyish to blackish, puberulous; bracts persistent, to 0.9 mm long, spoon-shaped, reflexed adaxially hairy; bracteoles persistent, to 0.7 mm long, adaxially hairy. Staminate flowers: pedicels ca. 5.6 x 1 mm, the diameter even throughout; receptacle flat, ca. 2 x 4.8 mm; tepals chartaceous, ovate, ca. 4.2 X 4.2 mm (inner whorl slightly smaller), at anthesis forming a cup ca. 6 mm diam. erect, reddish gray, adaxially tomentose; stamens of whorls I and II, the anthers sessile, chubby, broadly elliptical, ca. 1.8 X 3.2 mm, with a few hairs at base, the locelli 2, apical, introrse, the glands absent; whorl III columnar, ca. 1.2 x 1 mm, with a few hairs at base, the locelli 4, the upper pair latrorse, the lower pair extrorse, the glands globular, ca. 1.2 mm diam.; whorl IV absent; all stamens reddish; pistillode absent (minute, to 0.6 mm long). Pistillate flowers: pistil ca. 1.7 X 0.8 mm; ovary ovoid, ca. 0.8 mm long, glabrous. Fruits unknown.

  • Discussion

    Field notes. Trees to 12-15 m tall and 10-12 cm diam.; buttresses small; outer bark smooth (thin, fragile, finely fissured and chipped), brownish red in section; inner bark ca. 3 mm thick, somewhat fibrous, pale yellow; wood yellow, wood aromatic. Tepals yellowish.

    Vegetatively Rhodostemonodaphne revolutifolia is a very distinctive species with conspicuously revolute leaves, a rare condition in the family. The inflorescences are distinctly cymose, with persisting, recurved bracts and bracteoles. The most striking feature of the species are the two-locellate outer stamens of the staminate flowers, characteristic of Endlicheria. However, the vestigial four-locellate staminodia of the pistillate flowers place it in Rhodostemonodaphne.

  • Distribution

    Known from two collections from central French Guiana, at 100-350 m, in rain forest. Both flowering collections were made in the month of August, at the beginning of the dry season.

    French Guiana South America|