Solanum aspersum S. Knapp, 2010

Knapp, Sandra, 2013, A revision of the Dulcamaroid Clade of Solanum L. (Solanaceae), PhytoKeys 22, pp. 1-432 : 62-65

6. Solanum aspersum S. Knapp , PLoS ONE 5(5): e10502. 2010 Figure 18

Type.

Colombia. Putumayo: vertiente oriental de la Cordillera, entre Sachamates y San Francisco de Sibundoy, 1600-1750 m, 30 Dec 1940, J. Cuatrecasas 11471 (holotype: COL; isotypes: F [F-1335119], US [US-1799731]).

Description.

Woody vine, of unspecified length or height. Stems densely and evenly pubescent with antrorsely curved simple uniseriate trichomes 0.5-1.5 mm long, these few-celled with a large basal cell, arising from expanded bases and eventually deciduous; new growth densely pubescent with simple uniseriate trichomes to 1.5 mm long, these pale straw-colored in herbarium specimens; bark of older stems greenish brown, minutely tuberculate from the bases of the deciduous trichomes. Sympodial units plurifoliate. Leaves simple, (1-)3.5-9 cm long, (0.6-)1.5-4.6 cm wide, ovate to narrowly ovate, widest in the basal third, membranous or chartaceous, strongly discolorous, the upper surfaces evenly pubescent on veins and lamina, the trichomes to 2 mm long, simple, uniseriate, arising from expanded bases giving the lamina surface a tuberculate appearance, the lower surfaces densely and evenly pubescent with simple uniseriate trichomes to 2 mm long, these 2-3-celled with the basal cell largest, denser on the veins; primary veins 7-9 pairs, impressed above in herbarium specimens; base truncate or shallowly cordate; margins entire, not revolute; apex acute to acuminate; petioles 0.7-2 cm long, densely pubescent with simple trichomes like those of the stems and leaves. Inflorescences terminal on leafy short shoots, 3-15 cm long, globose to ellipsoid in outline, branching many times, with 2 principal basal branches, with 12-60 flowers, densely pubescent with simple trichomes; peduncle 0.5-3 cm long, the branching very near the junction with the stem; pedicels 0.5-0.8 cm long, <0.5 mm in diameter at the base and apex, pubescent with 1-2-celled simple trichomes to 1.5 mm long, spreading at anthesis, articulated near the base from a small sleeve, leaving a small peg on the axis; pedicel scars irregularly spaced 1-10 mm apart, the inflorescence rachis bending at almost right angles at articulation points. Buds narrowly ellipsoid, the corolla strongly exserted from the calyx tube. Flowers all perfect, 5-merous. Calyx tube ca. 2 mm long, conical, the lobes 0.5-1 mm long, deltate to broadly deltate, pubescent with simple trichomes, these sparser than on the rest of the inflorescence. Corolla 1.2-1.7 cm in diameter, white, pink or "pale blue" (violet?), narrowly stellate, lobed nearly to the base, the lobes 6-7 mm long, 1.5-2 mm wide, reflexed at anthesis, densely pubescent abaxially with weak simple papillate trichomes to 0.5 mm long, these denser on tips and margins, glabrous adaxially. Filament tube <0.5 mm, the free portion of the filaments ca. 0.5 mm long, glabrous; anthers 4-4.5 mm long, ca. 1 mm wide, ellipsoid, poricidal at the tips, the pores lengthening to slits with age. Ovary glabrous; style 5-6 mm long, pubescent with weak simple trichomes to 0.5 mm, more densely pubescent in the basal half; stigma capitate-truncate, the surface minutely papillose. Fruit a globose berry, ca. 1.3 cm in diameter (immature?), green or yellowish green, the pericarp thin and shiny, glabrous; fruiting pedicels 0.9-1 cm long, 1-1.5 mm in diameter at the base, woody and spreading. Seeds not seen from mature berries, apparently 10+ per berry and flattened reniform. Chromosome number: not known.

Distribution

( Figure 19 ). Solanum aspersum occurs in widely separated and isolated populations along the Andes from central Ecuador into Colombia, from 1600 to 2500 m.

Ecology.

Montane forests and forest margins.

Conservation status.

Vulnerable/Near Threatened (VU/NT); EOO>50,000 km2 (LC) and AOO>5,000 km2 (LC); the widely separated, isolated populations and few collections, however, mean that this species is of conservation concern. See Moat (2007) for explanation of measurements.

Discussion.

The few specimens of Solanum aspersum have usually been annotated as the more common and widely distributed Solanum aureum , also from Andean Ecuador. Solanum aspersum differs from that species in its simple uniseriate, rather than congested-dendritic, pubescence and in the elongate buds that open to deeply stellate flowers. Specimens of Solanum aureum from Azuay province in Ecuador have shiny adaxial leaf surfaces like those of Solanum aspersum , but always have the characteristic golden dendritic pubescence of that species rather than the simple pubescence of Solanum aspersum . The leaves of Solanum aspersum are usually more cordate than those of Solanum aureum , but some populations of Solanum aureum approach Solanum aspersum in overall leaf morphology at first glance. Solanum aspersum has a very scattered distribution all along the Andes from northern Colombia to central Ecuador and is likely to be found in more of the intervening parts of the cordilleras, but it is apparently rare and easily overlooked.

A single collection from Cajamarca in northern Peru (Diaz et al. 9717, NY) with simple trichomes on the inflorescence and completely glabrous leaves may also be this species; it shares the elongate buds and simple trichomes, but may represent a different taxon.

Specimens examined.

Colombia. Antioquia: Frontino, Nutibara, region Muri, camino hasta La Blanquita, 1440 m, 10 Jul 1986, Acevedo et al. 1213 (US); Urrao, between Urrao and caicedo, 21 km E of Urrao, near high point on road, 2710 m, 27 Feb 1989, MacDougal et al. 4251 (MO). Cauca: between La Cumbre and Quebrada La Isla, headwaters of Río Dinde, 28 Aug 1944, Core 1111 (US); Cundinamarca: Chiquinquirá, 2500 m, 17 Feb 1950, Sneidern 5825 (S).

Ecuador. Napo: Parroquia Cosanga, 6 kms de la carretera Cosanga-El Aliso, 2200 m, 23 Aug 1990, Jaramillo et al. 12110 (MO); Cantón Quijos, Reserva Ecológica Antisana, Río Aliso, 8 km al suroeste de Cosanga, 2500 m, 15 Nov 1998, Vargas et al. 3043 (MO). Pichincha: Reserva Florística-Ecológica “Río Guajalito", km 59 de la carretera antigua Quito-Santo Domingo de los Colorados, a 3.5 km al NE de la carretera, 2200 m, 28 Mar 1987, Zak 1857A (F, MO).

Figures

Figure 18. Solanum aspersum S. Knapp. (A-C drawn from MacDougal et al. 4251 D-E from Zak 1857 A). Originally published in Knapp (2010). Illustration by Bobbi Angell.

Figure 19. Distribution of Solanum aspersum S. Knapp