Solanum manabiense, S. Stern,

Stern, Stephen, Bohs, Lynn, Giacomin, Leandro, Stehmann, João & Knapp, Sandra, 2013, A Revision of Solanum Section Gonatotrichum, Systematic Botany 38 (2), pp. 470-496 : 488

6. SOLANUM MANABIENSE S.Stern,

J. Bot. Res. Inst. Texas 3(2): 504. 2009.

—TYPE: ECUADOR. Manabí: Pacoche Reserve , road from Manta to San Lorenzo , ~ 2 km Wof El Aromo, 01 ° 04 ' 09.5 '' S, 80 ° 52 ' 32 '' W, 350 m, 8 Feb 2009 (fl, fr), S. Stern & E.J. Tepe 377 (holotype: QCNE!; isotypes: BM!, F-2295591!, QCA!, MO-6262688!, NY!, UT!).

Rhizomatous herb, sometimes slightly woody at the base, 1.5–4 dm tall. Stems sparsely to densely pubescent with two- celled, unbranched, straight hairs. Sympodial units bifoliate, geminate. Leaf blades 1–6 + 0.5– 3 cm, elliptic to ellipticovoid, chartaceous to membranaceous, nearly glabrous to sparsely pubescent adaxially and abaxially with one or two-celled, unbranched, straight hairs, these lying flat along the blade, denser along veins; base rounded to obtuse, often decurrent into petiole; apex acute to obtuse; petioles 0.5–1 cm, moderately pubescent with unbranched straight hairs. Inflorescence with 1–5 flowers, the axes sparsely to moderately pubescent with unbranched hairs; peduncle absent; rachis absent to ca. 1 mm; pedicels 5–15 mm in flower, 10–20 mm in fruit. Flowers with the calyx 3–10 mm long, the tube 1–3 mm, the lobes 2–7 + 0.5–1.5 mm, linear-lanceolate, moderately to densely pubescent. Corolla 0.4 –1 cmin diameter, rotate with abundant interpetalar tissue, chartaceous to membranaceous, white, the tube 2–3 mm long, the lobes very short, 1–2 + 0.5 –1 mm, triangular, acute at apices, sparsely to moderately pubescent abaxially and on margins with 2 or 3-celled unbranched, straight hairs, glabrous adaxially. Stamens 2–4 mm long; filaments up to 1 mm long; anthers 1.5 –3 + 0.5–1.5 mm, oblong, the base cordate, the apex emarginate. Ovary glabrous; style 4–6 + 0.5– 1 mm, equal to or exserted beyond stamens; stigma to 1 mm wide. Berries 5– 12 mm in diameter, globose, white to yellow when immature, maturing semitransparent, drying brown, glabrous, the mesocarp watery and held under pressure until dehiscing explosively at maturity. Seeds 10–35 per fruit, ca. 2.5 + 1.5 mm, lacking an obvious notch where connected to placenta, the margin not swollen, the surface with fine raised ridges radiating from the center to the edges and shallow ridges running parallel to margin. Figure 11 .

Habitat and Distribution— A species known only from the central coast of Ecuador in Provinces Manabí and Guayas from sea level to 400 m in elevation ( Fig. 7 ).

Phenology— Flowering and fruiting specimens have been collected in February and July.

Conservation Status— Due to the very restricted geographic area in which S. manabiense occurs (<5,000 km 2), the small number of known populations (<5) and the few collections (4), it is given an IUCN Red List Status of Endangered.

Etymology— The epithet manabiense refers to Manabí Province of Ecuador where the type was found.

Additional Specimens Examined— ECUADOR. Guayas: 2– 4 km Efrom Recinto Olon, ca. 10 km Nof Manglaralto, 19 Feb 1974 (fl, fr), Gentry 10068 (MO). Manabí: Montecristi, Cerro Montecristi, eastern slopes above town, 18 July 1986 (fl, fr), Plowman & Alcorn 14334 (F, NY); Cerro Montecristi, Eslopes above town, 1 ° 03 ' 27 '' S, 80 ° 39 ' 58 '' W, 400 m, 7 Feb 2009 (fl, fr), Stern & Tepe 374 (QCNE, QCA, UT).

Notes— Solanum manabiense is unique in sect. Gonatotrichum due to the combination of its rhizomatous habit; bifoliate, occasionally geminate sympodia; leaves nearly glabrous on the abaxial surface; unbranched, straight (non-geniculate) hairs; small flowers with equal stamens; and seeds with unexpanded margins and no obvious notch at the attachment point to the placenta. It is apparently restricted to coastal Ecuador in the Guayas and Manabí provinces.

Solanum manabiense resembles S. olympicum, but the hairs of S. olympicum are geniculate whereas those of S. manabiense are straight. Solanum manabiense also resembles S. turneroides , but the latter is a more robust herb with heterantherous flowers that are much larger than those of S. manabiense . Solanum manabiense is also similar to S. deflexum , but the latter has leaves pubescent on both surfaces, is not rhizomatous, and has seeds with a swollen margin and pronounced notch where they connect to the placenta.

Figures

FIG. 11. Photos of type collection of S. manabiense (Stern & Tepe 377, QCNE). A. Habit. B. Flower; note hairs on stem and leaves. C. Fruit, with skin becoming transparent as turgor pressure increases. D. Roadside habitat in Manabí, Ecuador and author with type collection. Scale bars: A = 10 cm. B, C = 5 mm. (reprinted with permission of the Botanical Research Institute of Texas).

FIG. 7. Distribution of S. deflexum, S. lignescens, and S. manabiense.