Solanum loxophyllum, Bitter, Repert., 2011

Tepe, EJ & Bohs, L, 2011, A revision of Solanum section Herpystichum, Systematic Botany 36 (4), pp. 1068-1087 : 1080-1081

6. SOLANUMLOXOPHYLLUM Bitter,

Repert. Spec. Nov. Regni Veg. 11: 14. 1912.

—TYPE: ECUADOR. Chimborazo / Guayas: “ In silvis tropicalibus prope Puente de Chimbo,” Sep 1891 (fr), L. Sodiro 114/20 (holotype: B, [destroyed]; photos of holotype [F neg. 2668]: G–G00080136!, NY!, NY!; isotype: QPLS–SOLA0192!).

Vine, woody, climbing understory vegetation and canopy trees to 15 m or more. Stems slender, strong and wiry, the olderstems 8-shaped in cross section, reaching ca. 3 × 6 mm in cross section or larger, glabrous to sparsely pubescent, the trichomes slender, 0.8–1.5 mm long. Sympodial units plurifoliate. Leaves simple, the blades 2.5–8 × 0.8–3.5 cm, 2–3 times as long as wide, ovate to elliptical, somewhat fleshy, moderately sand-punctate, pubescent on the midvein adaxially with small trichomes 0.3–0.5 mm long, more rarely glabrous or pubescent across the leaf surface, glabrous to pubescent on the veins or the entire leaf surface abaxially; venation pinnate, with 3–4 pairs of secondary veins, these translucent in living material, inconspicuous and flush with the leaf surface on dried specimens, moderately sand-punctate; base rounded to truncate, oblique, the sides of the lamina 1–2 mm distant on the petiole; margins entire; apex acute; petioles 1–5 mm, moderately sand-punctate, pubescent adaxially. Internodes 1.5–2.2 cm. Inflorescences 1–11 cm long, simple or rarely once branched, extra-axillary to nearly leaf opposed, with 3–50 flowers (scars), the axes glabrous, slender and delicate; peduncle 0.3–0.5 cm, slender; rachis 2–10 cm; pedicels 3– 10 mm in flower, slender, 9–12 mm and slightly enlarged in fruit, 9–12 mm, somewhat thickened apically, glabrous, spaced 1–6 mm apart. Calyx 2.5–5 mm long, glabrous except for the margins which are sparsely ciliate apically, the tube 1–1.5 mm long, the lobes ca. 1.5 × 1.5 mm, rounded-deltoid, shortly apiculate at the tips, pale pinkish-white; fruiting calyx only slightly accrescent, the lobes 1.5–2 × ca. 1.5 mm. Corolla 0.8–1 cmindiameter, 3–5 mm long, stellate, membranaceous, white, the tube ca. 1 mm, the lobes 7–8 × 2–2.5 mm, lanceolate, attenuate at tips, glabrous adaxially and abaxially, the margins minutely ciliate apically. Stamens with filaments 0.8–1 mm, glabrous; anthers 2.5–3 × 1.2–1.5 mm. Ovary glabrous; style ca. 5 × 0.3 mm, cylindrical, glabrous; stigma capitate. Fruits 1–1.5 × 0.5–1.1 cm, ellipsoidal to conical, the apex somewhat pointed, glabrous. Seeds ca. 2 × 1.5 mm, ca. 0.5 mm thick, flattened, teardrop-shaped, light tan in color, the surface minutely rugose. Figure 1L–M .

Habitat and Distribution— Solanum loxophyllum is apparently endemic to the Pacific lowlands and low mountains of western Ecuador; 100–600(–850) m in elevation ( Fig. 7 ).

Phenology— Flowering and fruiting apparently occur throughout the year.

Etymology— The epithet loxophyllum (loxo = oblique in Greek) makes reference to the oblique leaf bases found in this species. The leaf bases of S. dolichorhachis , however, are much more markedly oblique than they are in S. loxophyllum .

Conservation Status— According to the IUCN red list categories ( IUCN 2010), S. loxophyllum is classified as B1a+biii (endangered). Although this species is common in the habitats where it occurs, deep shade of low to midelevation rainforests in western Ecuador, less than 1,500 km 2 of these habitats remain, and they continue to be converted to agricultural lands ( Dodson and Gentry 1991; C. Aulestia, Bilsa Biological Station, pers. comm.).

Common Names— Ecuador: Chinba chuba tape (Cayapa; Kvist 40522, AAU, QCA), chiro nairamo tape (Cayapa; Kvist 40437, AAU, BM), quinfo aran sili (Colorado; Kvist 40691, AAU, BM).

Uses— Ecuador: the leaves are used for pain relief and for healing of open wounds at joints. Leaves are applied to the affected joint (Kvist 40437). The flowersare crushed and rubbed on the body as a perfume (Kvist 40522). The plant is used for a bath (baño de caliente) when feeling cold (Kvist 40691).

Notes— Solanum loxophyllum is a climbing species closely allied to S. evolvulifolium , with which it has frequently been synonymized. It differs from S. evolvulifolium in its thin, but distinctly fleshy, larger leaves, less regular branching, sinuous rather than more or less straight branches, older stems that are 8-shaped in cross section, a tendency toward cauliflory, its high-climbing habit (individuals have been seen to climb to 12 m or more; E. J. Tepe, pers. obs.), and distribution under 850 m ( S. evolvulifolium has occasionally been collected as low as 250 m, but is most frequently encountered above 1,000 m).

Solanumloxophyllum canbedistinguished from other species of sect. Herpystichum by its fleshy leaves with inconspicuous veins (translucent in fresh material), cauliflorous inflorescences, and the distinctive older stems that are 8-shaped in cross section. The slender, delicate inflorescences emerge from the cleft between the two halves of the 8-shaped stems. Several collections from the area around Zapallo Grande and the Colorado community, Congoma Grande, are more robust and are more densely pubescent than collections from other areas. Herbarium specimens of S. loxophyllum typically dry dark to nearly black, a character shared with S. crassinervium .

The provenance of the type collection is rather vague, given that the town of Puente de Chimbo is no longer extant. One references states, however, that Puente de Chimbo was located at the end of the Chimbo valley, where the Chimbo river leaves the mountains and enters the plains, and turns from a south-flowing to a west-flowing river ( Wolf 1892, p. 132). This would place Puente de Chimbo near the current town of Bucay ( Bromley and Bromley 1975), and the locality falls well within the geographic and altitudinal range of other collections of S. loxophyllum .

Based on recent fieldwork, it appears that S. loxophyllum is widespread and common in the Pacific lowlands of Ecuador. It seems to be tolerant of intermediate levels of disturbance, and is abundant along trails and in secondary, but shady habitats. Flowering is apparently rather rare, and the flowers are inconspicuous and few in number. Consequently, S. loxophyllum is underrepresented in herbarium collections.

Additional Specimens Examined— ECUADOR. Azuay / Cañar: Manta Real, Río Patul, Sur de la Carretera La Troncal-Zhud, 2°33’S 79°20’W, 450– 800 m, 13 Jul 1991 (fr), R. B. Foster & B.Mitsui 13542 (F, QCA). El Oro:Hcda. Daucay, Limón – Playa, 3°28’S 78°45’W, 500 m, 22 Apr 1994 (st), X. Cornejo & C. Bonifaz 2478 ( NY); 11 km Wof Pinas on new road to Sta. Rosa, 850 m, 8 Oct 1979 (fl), C. H. Dodson et al. 9049 (MO, SEL). Esmeraldas: Mache- Chindul Ecological Reserve, Bilsa Biological Station, Mache Mountains, 35 km Wof Quinindé, 5 km Wof Sta. Isabel, 0°21’N 79°44’W, 500 m, 17 Feb 1996 (fl), J. L. Clark et al. 2054 (BM, MO, NY); Reserva Cotacachi-Cayapas, La Aguita, 0°28′48”N 78°26′24″W, 150 m, 26 Jun 1998 (infl), X. Cornejo & C. Bonifaz 6389 ( NY); Río Cayapa, Zapallo Grande, 1 km upriver Río Zapallo Grande, 0°48’N 78°54’W, 100 m, 29 Jun 1982 (infl), L. P. Kvist 40437 (AAU, BM); Río Cayapa, Zapallo Grande, 1 km upriver Río Zapallo Grande, 0°48’N 78°55’W, 100 m, 3 Jul 1982 (st), L. P. Kvist 40522 (AAU, QCA); environs of Lita, on the Ibarra-San Lorenzo RR, 550–650 m, 10 Jun 1978 (fl), M. T. Madison et al. 5154 (F, QCA); Mache-Chindul Ecological Reserve, Bilsa Biological Station, Mache Mountains, 35 km Wof Quinindé, 5 km Wof Sta. Isabel, 0°21’N 79°44’W, 500 m, 13 Feb 2009 (fl), E. J. Tepe & S. Stern 2726 (QCNE, UT); Reserva Ecológica Cotacachi-Cayapa, Charco Vicente, Río San Miguel, 0°43’N 78°53’W, 200 m, 20–31 Sep 1993 (fr), M. Tirado et al. 391 (MO, QCNE). Los Ríos: Río Palenque Biological Station, km 56 on the Quevedo-Santo Domingo Rd, 0°30’S 79°21’W, 150–220, 8 Jun 1974 (fl, fr), C. H. Dodson 5543 (SEL, US); Río Palenque Biological Station, km 56 on the Quevedo-Santo Domingo Rd, 0°30’S 79°21’W, 150–220 m, 29 Mar 1980 (fr), C.H.Dodson & A. Gentry 10040 (MO, SEL); Río Palenque Biological Station, km 56 on the Quevedo-Santo Domingo Rd, 0°30’S 79°21’W, 150–220 m, 5 Feb 2009 (st), E. J. Tepe et al. 2698 (QCNE, UT). Los Ríos or Pichincha: El Centinela at crest of Montañas Ila on road from Patricia Pilar to 24 de Mayo, 0°37′33”S 79°17′46″W, 600 m, 6 Feb 1979 (fl), C. H. Dodson 7389 (MO, SEL); El Centinela at crest of Montañas Ila on road from Patricia Pilar to 24 de Mayo, 0°37′33”S 79°17′46″W, 600 m, 20 Jul 1979 (fr), C. H. Dodson et al. 8626 (MO, SEL). Pichincha: Santo Domingo bypass ca. 3 km Sof Santo Domingo, 530 m, 8 Apr 1980 (fl), C. H. Dodson & A. Gentry 10359 (F, MO, SEL); Reserva Forestal ENDESA, Río Silanche, 0°06’N 79°02’W, 650–700 m, 9 Jun 1984 (fl, fr), J. Jaramillo (AAU, MO, QCNE); in the Colorado community “congoma grande” at km 23 on the Santo Domingo - Puerto Limon road, 0°21’S 79°22’W, 100 m, 21 Jul 1982 (st), L. P. Kvist 40691 (AAU, BM).

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.