Montane rain and cloud forest, especially on slopes or in disturbed areas, western Bolivia in Yungas de La Paz, 2200-3100 m.
Parsimony analyses of chloroplast ndhF sequence data place S. clandestinum in a clade with S. mapiriense, S. wendlandii, and S. allophyllum (the Wendlandii/Allophyllum clade of Bohs, 2005), but this clade is not well-supported (Bohs, unpubl. data). Nuclear ITS sequences indicate a relationship among S. clandestinum, S. mapiriense, and S. morellifolium, but this clade receives very little bootstrap support. Data from the nuclear waxy (GBSSI) gene allies S. clandestinum with S. mapiriense with 100% bootstrap support. Thus, three genes suggest an alliance between S. clandestinum and S. mapiriense, the latter another species endemic to the Bolivian Yungas that has been placed in Solanum section Allophyllum (Bohs, 1990). The elliptic leaves of S. mapiriense are much broader than those of S. clandestinum and the anthers are strongly tapered distally, in contrast to the oblong anthers of S. clandestinum. The fruits and seeds of S. mapiriense are incompletely known.
Solanum clandestinum is unique in its narrowly elliptic to lanceolate and usually subcoriaceous leaves, inflorescences with very short peduncles and long pedicels, white corollas, oblong anthers, and conspicuous, orange, few-seeded fruits. It is apparently restricted to the Yungas of La Paz in northwestern Bolivia. Specimens can vary from being nearly glabrous to abundantly pubescent, especially on the young stems. The hairs are unbranched but can have wide multiseriate bases and in some specimens these give the twigs a roughened or corky aspect.
Fruiting specimens of S. clandestinum can resemble S. confusum, another species of the Bolivian uplands. Solanum clandestinum is distinctive in its very short inflorescences, with the pedicels clustered and becoming long, slender, and curved in fruit. The seeds of S. clandestinum are not angled like those of S. confusum, and they always lack white pseudohairs on the surface. Flowers of S. clandestinum have white corollas and blunt, oblong anthers, whereas S. confusum flowers usually have violet corollas and tapered anthers. Solanum confusum lacks hairs with multiseriate bases.
Etymology: The specific epithet, meaning “hidden,” refers to the inconspicuous appearance of this species, which has probably led to it being overlooked until now. On a recent Bolivian field trip, three Solanum specialists ate lunch next to the plants without noticing them at first, despite the botanists’ interest in collecting this species. When one plant was finally recognized, several others were found in close proximity.
Bohs, L. 1990. The systematics of Solanum section Allophyllum.
Ann. Missouri Bot. Gard. 77: 398-409.
Bohs, L. 2005. Major clades in Solanum based on ndhF sequences.
Pp. 27-49 in R. C. Keating, V. C. Hollowell, & T. B. Croat (eds.), A festschrift for William G. D’Arcy: the legacy of a taxonomist. Monographs in Systematic Botany from the Missouri Botanical Garden, Vol. 104. Missouri Botanical Garden Press, St. Louis.
Nee, M., L. Bohs, & S. Knapp 2006. New species of Solanum and Capsicum (Solanaceae) from Bolivia, with clarification of nomenclature in some Bolivian Solanum.
Brittonia 58: 322-356.