Solanum ruizii S. Knapp, 1989

Knapp, Sandra, 2013, A revision of the Dulcamaroid Clade of Solanum L. (Solanaceae), PhytoKeys 22, pp. 1-432 : 211-214

32. Solanum ruizii S. Knapp , Bull. Brit. Mus. Nat. Hist. (Bot.) 19: 91. 1989 Figure 80

Solanum lanceolatum Ruiz & Pav., Fl. Peruv. 2: 33, tab. 164a. 1799, non Solanum lanceolatum Cav. 1795. Type: Peru. Huánuco: Muña, H. Ruiz & J. Pavón s.n. (lectotype, designated by Knapp, 2008c, pg. 320: MA [MA-747163]; isolectotypes: G [G00357895], MA [MA-747164, MA-747165]).

Solanum patulum Pers., Syn. 1: 223. 1805, non Solanum patulum (L.) Roth, 1800. Type: Based on Solanum lanceolatum Ruiz & Pav., non Solanum lanceolatum Cav., 1795.

Solanum patulum Pers. var. pilosistylum Bitter, Bot. Jahrb. Syst. 54, Beibl. 119: 9. 1916. Type: Peru. Huancavelica: Tayacaja, cerros al lado derecho del Río Mantaro al sur de Surcubamba, 3800 m, 12 Mar 1913, A. Weberbauer 6477 (holotype: B, destroyed; lectotype, designated by Knapp 1989, pg. 91: MOL; isolectotypes: G [G00070195], MOL [2 sheets]).

Solanum patulum Pers. forma album J.F.Macbr., Publ. Field Columbian Mus., Bot. Ser. 8: 111. 1930. Type: Peru. Huánuco: Tambo de Vaca, 3900 m, 10 Jun 1923, J.F. Macbride 4441 (holotype: F [F-535527]; isotypes: G [G00070196], MA [MA-205962], US [US-1592826], W [W-1936-3811]).

Type.

Based on Solanum lanceolatum Ruiz & Pav., non Solanum lanceolatum Cav. 1795.

Description.

Shrubs or small trees, 2-6 m tall. Stems densely pubescent with golden-yellow echinoid trichomes, these often elongate and tree-like; leaf scars somewhat raised; new growth densely pubescent with yellow echinoid and tree-like trichomes both above and below. Bark of older stems pale yellowish-white, glabrate. Sympodial units plurifoliate. Leaves narrowly elliptic, 7-13.5 cm long, 3-4 cm wide, the adaxial surfaces drying black with scattered golden echinoid and tree-like trichomes, these denser along the veins, the abaxial surfaces pubescent with the same echinoid trichomes, not drying as dark as the upper surfaces; primary veins 7-8 pairs, pubescent; base acute, not decurrent on to the petiole; margins entire; apex acuminate; petiole 1-1.5 cm long. Inflorescences terminal, becoming lateral with overtopping of the shoot, very large, 12-15 cm long, narrowly elliptic in outline, branching 8-10 times, with 10-25 flowers, each branch 0.5-3 cm long, densely pubescent with echinoid and tree-like trichomes; peduncle 1-2 cm long; pedicels 1.8-2.2 cm long, tapering from a basal diameter of 0.5-1 mm to an apical diameter of 1-1.5 mm, sparsely to densely pubescent with golden echinoid and tree-like trichomes, deflexed or horizontal at anthesis, articulated at the base and inserted in a sleeve ca. 0.5 mm long; pedicel scars closely spaced and clustered at the inflorescence branch tips. Buds ellipsoid, the corolla strongly exserted from the calyx tube. Flowers all perfect, 5-merous. Calyx tube 4-6 mm long, conical, the lobes 4-5 mm long, narrowly triangular, pubescent abaxially with the same trichomes as those of the pedicels, densely pubescent with golden dendritic trichomes adaxially. Corolla 4-4.8 cm in diameter, rotate-stellate, violet, very large and showy, lobed 1/2 of the way to the base, the lobes 23-25 mm long, 12-15 mm wide, planar or slightly cupulate at anthesis, densely pubescent abaxially with golden dendritic trichomes and with a few dendritic trichomes along the main veins adaxially. Filament tube minute or absent; free portion of the filaments ca. 1 mm long, glabrous; anthers ca. 5 mm long, 1-1.5 mm wide, loosely connivent, poricidal at the tips, the pores becoming slit-like with age. Ovary glabrous or with a few golden dendritic trichomes at the apex; style 1-1.2 cm long, densely pubescent at the base with golden dendritic trichomes; stigma bilobed, the surface minutely papillose. Fruit a globose berry ca. 1.1 cm in diameter (immature?), purplish-black with thin pericarp; fruiting pedicels 1.5-2 cm long, somewhat woody, erect or nodding,. Seeds ca. 30 per berry, c. 3.5 mm long, 3 mm wide, reddish-brown, flattened lenticular, the surfaces minutely pitted. Chromosome number: not known.

Distribution

( Figure 81 ). Endemic to central Peru from Depts. Huánuco to Huancavelica; from 3000-4000 m.

Ecology.

In moist situations in cloud forests and forest margins; often growing in open grassy areas.

Common names.

Peru. uruhuacta (Macbride 4351)

Conservation status. Vulnerable (VU); EOO <10,000 km2 (VU) and AOO <4,500 km2 (NT). See Moat (2007) for explanation of measurements.

Discussion.

Solanum ruizii is certainly one of the most spectacular members of the Solanum nitidum species group with its large, deep purple flowers. All of the specimens of this species characterize it as being very showy. Label data on Woytkowski 147 (F) state that Solanum ruizii is "very common up to 3600 m.a.s level. Sometimes, growing in open places, attains considerable height and forms trees". Solanum ruizii has not been collected since the early part of the 20th century, but large-scale habitat destruction probably accounts for this. Collections of this species come from slightly drier areas than typical 'ceja de la montaña’ vegetation in which other members of the Solanum nitidum group (sensu Knapp 1989) occur. These drier areas are characterized by extensive expanses of high elevation grassland or ‘pajonal’.

Solanum ruizii can be distinguished from its closest relative Solanum cutervanum by flower size and by the number of seeds in the berries (ca. 30 versus only 7-8 in Solanum cutervanum ). Mature fruits of Solanum ruizii are not known, but the label on Pearce s.n. from Muña states they are “large”, suggesting that the fruits I have observed are immature.

Holotypes or lectotypes for Ruiz and Pavón names in the Madrid herbarium (MA) not specifying a particular sheet are not sufficiently precise. Knapp (1989) lectotypified Solanum lanceolatum citing only a sheet in MA; this was rectified in 2008 by citation of the particular sheet ( Knapp 2008c).

Specimens examined.

Peru. Huancavelica: Tayacaja, Huaribamba, 1 km before Huari, 3170 m, 28 Jul 1968, Saunders 1173 (F); Tayacaja, Tayacaja, 3700 m, 10 Aug 1949, Velarde Nuñez 2008 (US); Huánuco: Tambo de Vaca, 3963 m, 10 Jun 1923, Macbride 4351 (G, US); Muña, May 1863, Pearce 156 (BM); Junín: between Acopalca and Huari in steep canyon, NE of Huancayo, 4024 m, 19 Aug 1977, Duncan et al. 2737 (NY).

Figures

Figure 80. Solanum ruizii S. Knapp. (A-B drawn from Macbride 4351). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 81. Distribution of Solanum ruizii S. Knapp.