Solanum turgidum S.Knapp

Authority

Knapp, Sandra D. 2002. section (Solanaceae). Fl. Neotrop. Monogr. 84: 1-404. (Published by NYBG Press)

Family

Solanaceae

Scientific Name

Solanum turgidum S.Knapp

Type

Type. Venezuela. Sucre: Península de Paria, Cumbre de Estrella, W of Manacal, N of El Paujil, low cloud forest on steep ridges, 800-850 m, 10o40'N, 62°41 W, 17 Oct 1984, Knapp & Mallet 6765 (holotype, MY; isotypes, BH, K, NY, US, VEN).

Description

Species Description - Small trees, 3-6 m tall; young stems and leaves minutely golden-puberulent with erect uniseriate trichomes less than 0.1 mm long; stems of live plants green, not winged; bark of older stems grayish-brown, smooth. Sympodial units difoliate, geminate. Leaves obovate to elliptic, widest at or just distal to the middle, glabrous on both surfaces, but occasionally with a few minute uniseriate trichomes along the midrib near the petiole; major leaves 10-25 x 5-15 cm, with 5-7 pairs of main lateral veins, these prominent and occasionally yellowish beneath, the apex acute, the base acute, not decurrent onto the petiole; petioles 1-2 cm long; minor leaves differing from the major ones in size and shape, elliptic to orbicular, 5-9.5 x 3.5-8.5 cm, the apex acute to rounded, the base acute; petioles 4-6 mm long. Inflorescences appearing terminal on the terminal node due to the slow expansion of leaves, but on other nodes opposite the leaves, rather stout, simple, but occasionally once-furcate, 1.5-4 cm long, 5-30-flowered, minutely golden-puberulent like the stems and young leaves, the trichomes denser near the distal end; pedicel scars closely spaced, but not markedly overlapping, beginning very near the base of the inflorescence. Buds globose when young, later ellipsoid with the exsertion of the corolla, the corolla strongly exserted, 3-4 times as long as the calyx tube. Pedicels at anthesis erect, pale green, 5-7 mm long, tapering from the base of the calyx tube to á slender base ca. 0.5 mm diam. Flowers with the calyx tube broadly cup-shaped, appearing woody in dry specimens, 1-1.5 mm long, the lobes broadly deltoid, 0.3-1 mm long, edged white, the tips minutely papillose, the entire calyx puberulent with the same erect golden uniseriate trichomes as the rest of the inflorescence; corolla white with a green center, each lobe with a green abaxial stripe and a single medial adaxial ridge, the ridge apparent even in dry specimens, 1-1.2 cm diam., lobed nearly to the base, the lobes planar at anthesis, the tips of the lobes slightly cucullate, the tips and margins puberulent with minute uniseriate trichomes like those of the buds; anthers 2.5-3.5 x 0.75-1 mm, poricidal at the tips, the terminal portion thickened and paler, the pores teardrop shaepd; free portion of the filaments 0.25-0.5 mm long, the filament tube ca. 0.25 mm long; ovary densely golden-pubescent with uniseriate trichomes 0.1-0.3 mm long; style straight, 5-6 mm long; stigma minutely capitate, the surface minutely papillose. Fruit a globose berry, tinged purplish when young, green when ripe, 1-1.2 cm diam., the surface dull due to the continued presence of minute uniseriate golden trichomes, these not deciduous, 0.1-0.3 mm long; fruiting pedicels swollen, woody, and erect, 8-9 mm long, 1 -2 mm diam. at the base. Seeds (immature), dark brown in dry specimens, ovoid-reniform, 2-2.5 x 1-1.5 mm, the surfaces minutely pitted. Chromosome number: n = 12 (voucher Knapp & Mallet 6765).

Discussion

Solatium turgidum is related to S. triste and S. chlamydogynum, both also of coastal Venezuela (see Knapp, 1991b). They share several homoplastic synapomorphies: branched pubescence, thickened calyx lobes, and incrassate seed margins. Solanum turgidum is easily distinguished from S. triste or S. chlamydogynum by its greenish flowers, glabrous leaves, and short, stout fruiting pedicels. The trichomes on the style base of S. turgidum appear uniseriate and simple under the dissecting microscope, but when viewed at high magnifications with the SEM, it is clear that at least some of them are furcate (see Fig. 11). This possession of both branched and simple trichomes is common in the S. sessile species group.

Distribution

Known only from the ridges of the Peninsula de Paria in eastern Venezuela, in cloud forest at ca. 800 m.

Venezuela South America| Sucre Venezuela South America|