Solanum amblophyllum
Citation:
Bot. misc. 2: 231. 1831.
Type:
Peru. Lima: Obrajillo, in the valley of Canta, sin. coll. (holotype, K).
Last edited by:
Knapp, S.
Written by:
Knapp, S.
Habit:
Dense shrubs 1-2 m tall; young stems and leaves densely red-papillose, the papillae ca. 0.1 mm long; older stems glabrous; bark of older stems dark grayish-brown.
Sympodial structure:
Sympodial units plurifoliate.
Leaves:
Leaves narrowly elliptic, coriaceous, crinkled and glabrous above in dry specimens, densely pubescent along the midrib beneath, the trichomes uniseriate, simple, 0.5-1 mm long, crowded at the junctions of the midrib and the main lateral veins, leaf margins revolute, blades 4.5-13 x 1.7-3 cm, with 6-10 pairs of main lateral veins, these not visible above, prominent beneath, the apex rounded, the base acute, decurrent onto the petiole; petioles 0.6-1 cm long.
Inflorescences:
Inflorescences terminal, later becoming lateral, occasionally opposite the leaves, branched several times, 2-5 cm long, 10-25-flowered, but with only a few flowers at a time, glabrous or glandular-resinous; pedicel scars irregularly spaced 1-2 mm apart, beginning ca. 1 cm from the base of the inflorescence. Buds flattened apically when young, later globose, the corolla soon exserted from the calyx tube. Pedicels at anthesis deflexed, thick and fleshy, 1-2 cm long, tapering from the base of the calyx tube to a base 1 mm in diam.
Flowers:
Flowers with the calyx tube broadly cup-shaped, ca. 1.5 mm long, the lobes rounded-triangular, often auriculate, 1-1.5 mm long, the margins thickened and paler, glabrous; corolla white, fleshy, 1.2-1.6 cm in diam., lobed 2/3 of the way to the base, the lobes planar at anthesis, the tips and margins of the lobes densely papillose; anthers 4-4.5 x 1-1.5 mm, poricidal at the tips, the terminal 0.5 mm thickened and paler, the pores tear-drop shaped; free portion of the filaments 0.25-0.5 mm long, the filament tube ca. 0.5 mm long; ovary glabrous; style straight, 6-8 mm long; stigma capitate, bright green in live plants, the surface minutely papillose.
Fruits:
Fruit a globose, green berry, 1-1.3 cm in diam.; fruiting pedicels woody and deflexed, 1.2-1.5 cm long, ca. 1.5 mm in diam. at the base.
Seeds:
Seeds dark brownish in dry material, greenish-tan in live plants, flattened-reniform, 3.5-4 x 2-2.5 mm, the margins incrassate and somewhat paler, the surfaces deeply pitted.
Distribution:
On the western slopes of the Andes in the department of Lima, Peru, from 2500 to 3500 m.
Phylogeny:
Solanum amblophyllum 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 amblophyllum is a shrub of open areas at high elevations and is most similar and probably closely related to S. barbulatum of northern Peru. It differs from that species in its plurifoliate sympodia, branched inflorescences, larger flowers, and distinctive leaves. The upper surfaces of dried leaves of S. amblophyllum have an unmistakable crinkled, crêpe-paper appearance, making this species easy to identify. The flowers are large and fleshy but rather inconspicuous as they hang down amongst the foliage. The trichomes on the undersides of the leaves are quite dense and their structure is difficult to determine from dried material. The trichomes are always simple and uniseriate. The position of the trichomes is distinctive in S. amblophyllum. They occur on the midrib on either side of the primary nerves of the leaf and are not strictly in the vein axils as in S. barbulatum and members of the S. nudum species group.
Solanum amblophyllum has a limited distribution, but is rather common where it occurs. In the area in which I collected this species, it was a common streamside shrub just below the snowline. Few specimens of S. amblophyllum are found in North American or European herbaria, but it is well represented in Peruvian herbaria.