Solanum barbulatum
Citation:
Ann. K. K. Naturhist. Hofmus. 7: 6. 1892.
Type:
Peru. Cajamarca: Cutervo, 1879, Jelski 56 (holotype, W [F neg. 33048]; frag. F).
Last edited by:
Knapp, S.
Written by:
Knapp, S.
Habit:
Shrubs 1.5-5 m tall; young stems and leaves glabrous and shiny, occasionally with a few uniseriate trichomes ca. 0.3 mm long, the young leaves red-papillose; bark of older stems shiny and whitish or gray.
Sympodial structure:
Sympodial units difoliate, geminate.
Leaves:
Leaves elliptic, widest at the middle, glabrous above, glabrous to pubescent with uniseriate simple or branched trichomes along the veins and in the vein axils beneath, the trichomes occasionally extending to the lamina; major leaves 2.5-13 x 0.8-3.7 cm, with 8-13 pairs of main lateral veins, these often strongly parallel, prominent above and beneath, the apex acute, the base acute; petioles 2-5 mm long; minor leaves differing from the major ones only in size, 1.3-3 x 0.6-1.4 mm, the apex acute, the base acute; petioles 2-3 mm long.
Inflorescences:
Inflorescences opposite the leaves, simple, 0.5-2 cm long, 2-8-flowered, usually glabrous, but occasionally with a few uniseriate trichomes along the rhachis; pedicel scars closely spaced but not overlapping. Buds flattened perpendicular to the pedicel when very young, later globose, the corolla soon exserted from the calyx tube. Pedicels at anthesis deflexed, 0.8-1.3 cm long, tapering from the base of the calyx tube to a slender base 0.5-0.75 mm long.
Flowers:
Flowers with the calyx tube broadly cup-shaped, ca. 1 mm long, the lobes broadly deltoid, fleshy, appearing woody in dry specimens, 0.5-1 mm long, glabrous and shiny; corolla white, fleshy, 0.8-1.2 cm in diam., lobed 2/3 of the way to the base, the lobes planar or somewhat deflexed at anthesis, the tips and margins of the lobes densely papillose; anthers 2.5-4 x ca. 1 mm, poricidal at the tips, the terminal 0.5 mm thickened and paler, the pores tear-drop shaped; free portion of the filaments 0.05-0.1 mm long, the filament tube 0.25-0.5 mm long; ovary glabrous; style straight, 5-6 mm long; stigma a widened area on the tip of the style, the surface minutely papillose.
Fruits:
Fruit a globose, green berry, 1-1.5 cm in diam.; fruiting pedicels woody, erect or deflexed, 1-1.5 mm long, ca. 1 mm in diam. at the base.
Seeds:
Seeds dark brown, flattened-reniform, 2-4 x 2-3 mm, the margins incrassate and paler, the surfaces minutely pitted.
Distribution:
In the Andes of southern Colombia, Ecuador and northern Peru, from 2500 to 4000 m.
Phylogeny:
Solanum barbulatum is a member of the Solanum amblophyllum species group (Knapp, 2002) of the Geminata clade (Bohs, 2005).
References:
Knapp, S. 2002. Solanum section Geminata (G. Don) Walpers (Solanaceae).
Flora Neotropica 84: 1-405.
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.
Solanum barbulatum is similar morphologically to both S. psychotrioides (Colombia) and S. amblophyllum (Peru) but differs from those species in its small flowers and short fruiting pedicels. The trichomes in the vein axils of S. barbulatum are thinner and weaker than those of S. psychotrioides and usually dry white. The bark of S. barbulatum is usually bright white in dry specimens and appears to peel off in thin sections from the stem. Populations of S. barbulatum are more pubescent in Peru and progressively become more glabrous into Colombia, but much variation exists and populational samples are not known.