Iochroma cyaneum (Lindl.) M.L.Green

Solanaceae, Jennifer M Edmonds. Oliganthes, Melongena & Monodolichopus, Maria S. Vorontsova & Sandra Knapp. Flora of Tropical East Africa. 2012

Type

Type: Herb. Hort. London, introduced from Loja, Ecuador, Hartweg s.n.(K! in herb Hooker, syn.); collected from the village of Gonzanamá and the city of Loja, Ecuador, Seemann 883 (K!, syn.), typ. cons.

Morphology General Habit

Shrubs or woody herbs, 1–4 m tall, often laxly branched.

Morphology Stem

Stems pilose or villous with long simple or simple and branched eglandular hairs, denser on young stems

Morphology Leaves

Leaves green, ovate-lanceolate to lanceolate, 5–12(–14) × 2.6–5.4(–6.6) cm, bases cuneate, margins entire to sinuate, apices acute to obtuse, moderately pilose above, floccose beneath with long simple or simple and branched hairs; petioles 1.4–6 cm long. Inflorescences congested terminal, subaxillary or axillary fascicles of 8–24+ flowers; pedicels erect or spreading, pilose or villous, 0.9–1.6(–2.7) cm long in flower

Morphology Reproductive morphology Flowers Calyx

Calyx urceolate or cupulate, enclosing the basal quarter to third of corolla tube, 7–12 × 5–9 mm, with five triangular teeth 0.8–2.5 × 0.8–3.5 mm, pilose externally

Morphology Reproductive morphology Flowers Corolla

Corolla usually blue, mauve or purple, sometimes with a whitish throat, tubular or trumpet-shaped, 3.2–4 cm long, with throat 9–12 mm diameter, tube long and often curved, ± 5 mm wide in centre, terminating in five to ten partially reflexed apical broadly triangular lobes 0.8–2 × 1.5–3 mm; basal part of tube tapering towards base, glabrous externally becoming puberulous toward the lobes

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens usually included, occasionally exserted; filaments 2.5–3.2 cm long; anthers yellow, elongate, 3–4.5 × 1–1.5 mm; often visible in corolla throat

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary conical to pyriform, 2.2–5 × 1.1–2.8 mm, glabrous; style 2.7–3.2 cm long, included; stigma 0.3–1 × 0.5–1 mm

Morphology Reproductive morphology Fruits

Fruit pale greenish-yellow to purplish-green conical berry, 1.8–2.2 × 1.2–1.7 cm, partly enclosed by expanded split calyx, with strong fruity scent

Morphology Reproductive morphology Seeds

Seeds yellow, discoid, 1 × 1.5 mm, flattened and foveolate; sclerotic granules spherical to ovoid, ± 0.5–1 mm diameter

Figures

Fig 14/1–7, p 68

Ecology

An escape from gardens and arboreta, occurring on roadsides; 850–1700 m

Conservation

Widespread; least concern (LC)

Note

Numerous other synonyms are given in Shaw (1998). No fruits were recorded from East African specimens, perhaps again reflecting the lack of necessary pollinators such as hummingbirds; the fruit and seed characters given above have been taken from Shaw (1998). Specimens identified as I. lanceolata Miers proved to belong to I. cyaneum, rather than to the yellow-flowered species described by Miers. Among the names used to identify East African cultivated material are Cestrum brevifolium Urb., Iochroma schlechtendalianum Dunal and I. lanceolata Miers. The latter was described as a yellow-flowered species by Miers, and although Lawrence & Tucker (1955) considered this to be a synonym of I. cyaneum, Shaw (1998) reported that the name lanceolatum had been misapplied by Hooker and synonymised it with I. gesnerioides (Kunth) Miers. He further proposed that many individuals represent hybrids between this latter species and I. cyaneum. One specimen ( Greenway 8769) whose flowers were described as “brownish red” had been identified as the red-flowered species I. coccinea Scheid. (a synonym of I. gesnerioides (Shaw, 1998)). However, Greenway collected this on the same day and from the same locality – Closeburn, Nairobi - as specimen 8772 whose flowers he recorded as being “almost black purple”. Both of these specimens are considered to belong to I. cyaneum. I have only seen one good African specimen of I. gesnerioides collected as a garden ornamental in Harare, Zimbabwe ( Biegel 5222!), whose flowers were “chinese lacquer red”. Many cultivars of I. cyaneum have been produced, and flower colour is particularly variable in this species; it is also known to alter with both maturity and drying. In addition, Shaw (1998) considered that the heterogenicity shown by this species is evidence of a hybrid origin of I. cyaneum, and that introgression from other species, including I. gesnerioides, may also have occurred, all contributing to the considerable morphological variability displayed by this species.

Distribution

Flora districts: K4 T ?2, T3 Range: Native to Andean Ecuador, widely grown as an ornamental shrub in Africa