Cinchona krauseana L.Andersson

  • Authority

    Andersson, Lennart. 1998. A revision of the genus (Rubiaceae--Cinchoneae). Mem. New York Bot. Gard. 80: 1-75.

  • Family

    Rubiaceae

  • Scientific Name

    Cinchona krauseana L.Andersson

  • Description

    Species Description - Shrub, to 4 m tall. Young branches glabrous or sparsely puberulous. Stipules glabrous, 0.4-0.8 X 0.4 cm; petioles 0.3-0.8 cm long, glabrous; leaf blades firmly chartaceous, 3.7-7 X 1.7-4.4 cm, ± elliptic (vaguely ovate to vaguely obovate, length:width ratio 1.5-1.9), ± broadly cuneate at base, rounded to (usually) broadly obtuse at apex, secondary veins 5-9 pairs, slightly impressed above, prominulous beneath, tertiary venation obscure on both sides, adaxial surface glossy, glabrous, abaxial surface glabrous throughout, margin slightly revolute, domatia absent. Inflorescence axes sparsely to rather densely puberulous. Calyx 3.2-3.6 mm long with the narrowly triangular lobes 1.5-1.9 mm and somewhat longer than tube, sparsely puberulous outside, glabrous inside, or minutely puberulous at the very base, with patches of colleters decurrent from the sinuses to near base, or only near base opposite sinuses; corolla pink, tube 12-20 mm long, villosulous inside below stamen attachments, lobes 5.5-9.7 mm long; filaments attached 2.8-6.4 mm (ca. 20-30% of tube length) above base of corolla tube in short-styled flowers (long-styled ones not seen), 5.311 mm long, anthers 3.9-1.1 X ca. 0.9 mm; ovary rather densely puberulous, 1.7-2.4 X 1.5-2.3 mm; style 2.9-3.1 mm long in short-styled flowers, stigmatic lobes 1.7-1.9 mm; disk glabrous. Capsules ± ellipsoid, 8-18 X 5-14 mm, basipetally dehiscent, with wood-like endocarp ca. 0.55 mm thick. Seeds ca. 5.1 X 3.9 mm including wing, wing margin weakly dentate.

    Distribution and Ecology - Distribution and habitat. Known only from the province of Chachapoyas, Amazonas department, N Peru (Fig. 13 F). The only altitudinal record is 2680 m.

  • Discussion

    Type. Peru. Amazonas: E of Chachapoyas, near Molinopampa, 2000-2300 m, Weberbauer 4331 (n.v.). The reason that this species was originally placed in Ladenbergia was obviously the basipetal dehiscence of the capsules. It also was recognized as a member of Ladenbergia by Standley (1936). However, all floral characters suggest its inclusion in Cinchona: presence of weakness lines in the corolla, reddish corolla color, densely villous margins of the corolla lobes, and long filaments in the short-styled flower morph. Acropetally dehiscent capsules occur in several species of both Ladenbergia and Remijia, and in Cinchona hirsuta capsules appear to start opening at both the base and the apex at the same time. This character must obviously not be overemphasized. Cinchona krauseana may in fact be readily confused with C. hirsuta and C. macrocalyx. It differs from both in having totally glabrous leaves (vs. usually ± pubescent, at least on petioles and the abaxial side of the midrib), leaf blades with the tertiary venation obscure (vs. ± distinct, at least toward the blade margin), corolla tube villosulous inside below stamen attachmens (vs. glabrous throughout, or sparsely villosulous around filament attachments). Although only a single seed was seen of C. krauseana, it was smaller (5.1 mm long) than any of the other two species (6.5-12 mm in C. hirsuta and 8-10 mm in C. macrocalyx). Cinchona krauseana differs further from C. hirsuta in having shorter calyx lobes (1.5-1.9 vs. 2.5-4 mm long) and from C. macrocalyx in having on the average larger flowers (corolla tube 12-20 vs. 9-13 mm long).