Solanum limoncochaense, Tepe,

Tepe, EJ & Bohs, L, 2011, A revision of Solanum section Herpystichum, Systematic Botany 36 (4), pp. 1068-1087 : 1079-1080

5. SOLANUM LIMONCOCHAENSE Tepe,

J. Bot. Res. Inst. Texas 3: 516. 2009.

—TYPE: ECUADOR. Sucumbíos: Limoncocha, Reserva Biológica Limoncocha , in wet primary forest near NW corner of lake, 250 m, 22 Jan 2009 (fl, fr), E. J. Tepe & S. Stern 2627 (holotype: QCA!; isotypes: BM!, MO!, MU–272379!, NY–NY01163478!, QCNE!, US!, UT!).

Herbaceous vine, terrestrial or climbing to ca. 1 m from ground. Stems slender, glabrous. Sympodial units plurifoliate. Leaves simple, the blades 3.5–7 × 3.5–8 cm, slightly wider than long, rounded, somewhat fleshy, moderately sand-punctate, glabrous; venation palmate with 5(–7) primary veins, these sparsely sand-punctate; base cordate; margins entire, slightly revolute on some leaves; apex rounded to obtuse to shortly acuminate; petioles 3–16 cm, moderately sand-punctate, glabrous. Internodes 2.5–20 cm. Inflorescences 4–8 cmlong, unbranched, extra-axillary, with 2–3 flowers, the axes glabrous; peduncle 1.3–4.5 cm, slender; rachis 0.9–1.5 cm; pedicels 15–25 mm in flower, 25–30 mm in fruit, slender, glabrous, spaced ca. 15 mm apart. Calyx 2.5–4.2 mm long, the tube 1–1.5 mm long, the lobes 1.5–2 × ca. 1.2 mm, rounded, acuminate at tips, glabrous to sparsely pubescent abaxially, densely pubescent adaxially, purplish; fruiting calyx slightly accrescent, the lobes 1–1.2 × 1.5–2 mm, truncate-acuminate. Corolla 1–1.6 cmindiameter, 5–8 mm long, stellate, membranous, white, the tube 1.5–2 mm, the lobes 6–10 × 1.5–3 mm, lanceolate, narrowly acute at tips, the apex papillose adaxially and abaxially, the margins ciliate apically. Stamens with filaments ca. 1 mm, glabrous; anthers 2–2.5 × ca. 1 mm. Ovary sparsely papillose; style 2–2.5 × ca. 0.3 mm, straight, cylindrical, stout, sparsely papillose in lower half; stigma capitate, somewhat 2-lobed. Fruits 1–3 × 0.6–3.2 cm, ovoid-rhomboid, flattened, the apex truncate to emarginate, greenish-brown to purplish near apex when immature, bronze-brown when mature, sparsely pubescent with hairs <0.1 mm to glabrous when mature, strongly fragrant with a sweet, heavy scent, juicy, the flavor sweet. Seeds 2–2.5 mm in diameter, lenticular, light reddish-brown, the surface minutely rugose. Figure 1A–C .

Habitat and Distribution— This species appears to be endemic to Sucumbíos Province (historically part of Napo Province), Ecuador, near the Laguna de Limoncocha, where it grows in terra firme primary forests and clearings; 240–300 m ( Fig. 7 ).

Phenology— Flowering specimens have been collected in Jan., June, Sept., and Oct.; fruiting specimens have been collected in Jan and Jun.

Conservation Status— According to the IUCN red list categories ( IUCN 2010), S. limoncochaense is classified as B1a+ biii (critically endangered) and D2 (vulnerable because of restricted area of occupancy). This species is only known from the terra firme forest near the northwest part of the Laguna de Limoncocha in western Ecuador. The four known collections of this species are all from this area, where it is common, but exploration of much of the Reserva Biológica Limoncocha did not reveal any additional populations (E. J. Tepe, pers. obs.). There is also a continuing decline in suitable habitats in the area due to deforestation for additional oil exploration, and an increase in the local population resulting from oil-associated jobs (H. Moya, Reserva Biológica Limoncocha, pers. comm.).

Etymology— Solanum limoncochaense is named for the Laguna de Limoncocha in western Ecuador, the only known collection locality of this species.

Notes— Solanum limoncochaense is one of the ground-trailing species and can easily be recognized by its simple, palmately veined leaves, glabrous vegetative parts, and stellate flowers. It is most similar to the Colombian S. dalibardiforme , which is pubescent throughout, has rotate-stellate corollas, and appears to be a strictly high-elevation species.

This species grows in dense patches on the rainforest floor and over fallen trees. It is a weak climber, and plants in the field were encountered climbing tree trunks up to ca. 1 m from the ground (E. J. Tepe and S. Stern, pers. obs.).

Additional Specimens Examined— ECUADOR. Sucumbíos: Limoncocha on Río Napo, 300 m, 18 Oct 1974 (fl), B. A. Drummond 7350 ( MO); environs of Limoncocha, 240 m, 16 Jun 1978 (fl, fr), M. T. Madison et al. 5327 (AAU, F, K, MO, NY, QCA, SEL); near northwest corner of lake, Limoncocha, Sep 1969 (fl), R. N. Mowbray 699104 ( MO).

Figures

FIG.1. Flowers fruits, and habit of Solanum sect. Herpystichum: A. Solanum limoncochaense, habit, flower, and bud. B. S. limoncochaense fruit in situ and C. in cross section (E. J. Tepe & S. Stern 2627, QCNE). D. S. trifolium flower and leaf (E. J. Tepe & S. Stern 2682, QCNE). E. S. phaseoloides habit, flower, and leaf (photo by W. H. Haber). F. S. crassinervium habit (E. J. Tepe & S. Stern 2729, QCNE), and G. flowers (S. Stern & E. J. Tepe 400, QCNE). H. S. evolvulifolium habit and flower, and I. fruit (immature) (E. J. Tepe & S. Stern 2671, QCNE). J. S. pacificum inflorescence with flowers, buds, and fruit (immature), and K. habit (E. J. Tepe et al. 2696, QCNE). L. S. loxophyllum habit, note adventitious roots at nodes, and M. older stem with inflorescences, note figure eightshaped stem (E. J. Tepe & S. Stern 2726, QCNE). Inflorescences emerge from the cleft between the two lobes of the stem.

FIG.7. Distribution of Solanum limoncochaense and S. loxophyllum.