Solanum macbridei Hunz. & Lallana, 1981

Knapp, Sandra, 2013, A revision of the Dulcamaroid Clade of Solanum L. (Solanaceae), PhytoKeys 22, pp. 1-432 : 170-172

25. Solanum macbridei Hunz. & Lallana , Lorentzia 4: 17. 1981 Figure 63

Type.

Peru. Cuzco: Quispicanchis, Marcapata, 12000 ft, 17 Oct 1937, D. Stafford 984 (holotype: K [K000585558]; isotypes: BM [BM000815938], F [F-1498721]).

Description.

Shrubs with many erect dichasial branches, 1-1.5 m tall, the branches and branchlets erect and densely packed. Stems densely pubescent with dendritic trichomes, these persistent; leaf scars very prominent, the stems strongly winged from the decurrent leaf bases; new growth purplish green, glabrous except for a few dendritic trichomes on the revolute leaf margins. Bark of older stems grey-brown, sparsely pubescent with dendritic trichomes. Sympodial units plurifoliate. Leaves simple, 0.9-2.3 cm long, 0.2-0.7 cm wide, narrowly elliptic, shiny, fleshy and coriaceous, both surfaces glabrous except for a few dendritic trichomes on the revolute margins and on the midvein of the adaxial surface; primary veins obsure, relatively few; base attentuate; margins entire, strongly revolute; apex acute, somewhat apiculate; petiole very short to absent, usually 1-2 mm long. Inflorescences terminal, appearing lateral from overtopping shoot growth, 0.2-1 cm long, compact and more or less globose, branching 2-4 times, with 2-5 flowers, the axis completely glabrous and shiny; peduncle 0.3-0.5 cm long, often absent and the inflorescence appearing to arise directly from the stem; pedicels 4.5-5 mm long, tapering from a basal diameter of 0.5 mm to an apical diameter of ca. 1 mm, deflexed and nodding at anthesis, glabrous, inserted in a prominent wrinkled sleeve 1-1.5 mm long; pedicel scars tightly spaced. Buds globose, later elliptic, the corolla strongly exserted from the calyx tube. Flowers all perfect, 5-merous. Calyx tube conical, ca. 0.5 mm long, the lobes broadly deltate, ca. 0.5 mm long, glabrous on both surfaces with a few simple trichomes to 0.5 mm long on the margins of the lobes. Corolla 1.4-1.7 cm in diameter, violet, rotate-campanulate, cupulate and nodding at anthesis, lobed 1/2 way to the base or less, the lobes 2-3 mm long, 2-3 mm wide, densely pubescent abaxially with dendritic trichomes, adaxially glabrous. Filament tube absent; free portion of the filaments ca. 1 mm long, glabrous; anthers ca. 2 mm long, 0.5-1.5 m wide, loosely connivent, poricidal at the tips, the pores becoming slit-like with age. Ovary glabrous or occasionally with a few scattered dendritic trichomes near the apex; style ca. 6 mm long, more or less densely pubescent with dendritic trichomes near the middle; stigma obscurely bilobed. Fruit a globose and slightly apically pointed berry, 6-9 mm in diameter, purplish-black, fleshy with thin pericarp; fruiting pedicels ca. 6 mm long, ca. 0.5 mm in diameter at the base, woody, deflexed. Seeds ca. 8 per fruit, ca. 5 mm long, 3 mm wide, pale reddish-brown, flattened lenticular, the surfaces minutely pitted. Chromosome number: not known.

Distribution

( Figure 64 ). S Peru to N Bolivia, 3800-4600 m.

Ecology.

Above timberline in boulder fields and among rocks in moist puna.

Conservation status. Possible Near Threatened (possible NT); EOO <75,000 km2 (LC) and AOO>10,000 km2 (LC). See Moat (2007) for explanation of measurements.

Discussion.

Solanum macbridei is morphologically one of the most distinctive members of the entire genus Solanum . It is unique in its campanulate corolla and in its small, coriaceous leaves. Sheets of this species have been identified as members of the Gentianaceae , Ericaceae and as the genus Fabiana Ruiz & Pav. ( Solanaceae ). The pedicel sleeve characteristic of the Solanum nitidum species group is very pronounced in Solanum macbridei , partly because the inflorescence is completely glabrous and thus the character is more easily visible than in other more pubescent species in the group.

In his original description of Solanum macbridei , Hunziker (1981) speculated that it was closely related to Solanum albescens (Britton) Hunz. (= Solanum leptocaulon van Huerck & Mull.-Arg.). Hunziker thought the anthers of both species dehisced by slits rather than pores (the synapomorphy for Solanum ), but he was incorrect in the case of Solanum macbridei , whose anthers are typically solanum-like, dehiscing by terminal pores that are more or less tear-drop shaped. The coriaceous leaves of Solanum leptocaulon are almost certainly related to its high elevation habitat, as are those of Solanum macbridei . Solanum leptocaulon is a species of uncertain affinities in Solanum (L. Bohs, pers. comm.), but is clearly also a Solanum with initially poricidal anthers that only later dehisce by slits.

Specimens examined.

Bolivia. La Paz: La Fabulosa, tin mine at the head of the Challana valley 80 miles north of La Paz, 4024 m, 3 May 1950, Brooke 6355 (BM, F); Larecaja, Cacacani, 4500 m, Dec 1860, Mandon 1499 (BM, K); Pedro Domingo Murillo, side valley 0.5 km up from Pongo on gravel road to Mina Alaska (=Mina Copacabana), 6.5 km W of Unduavi, 3850 m, 29 Oct 1984, Nee & Solomon 30182 (BH, GH, K); Pedro Domingo Murillo, 0.5 km up from Pongo on gravel road to Mina Alaska (Mina Copacabana), 3900 m, 9 May 2001, Nee et al. 51758 (BM, NY); Pedro Domingo Murillo, 3.5 km W of Pongo on road to Unduavi, 3850 m, 8 Mar 1984, Solomon & Stein 11660 (K).

Peru. Cusco: Quispicanchis, Marcapata, leaving village and heaving back to Cuzco, 11 km from peak, 4350 m, 23 Jul 1978, Aronson & Berry 541 (F, MO, USM, USM); Paucartambo, Qollatambo, Parque Nacional Manu, 3800 m, 8 Sep 1990, Cano 4180 (F, MO, USM); Paucartambo, Huáscar, Parque Nacional Manu, 3900 m, 9 Sep 1990, Cano 4225 (USM); Quispicanchis, Marcapata, 4000 m, 20 May 1954, Hincher P-1270 (F); 55 km E of Ocongate, 4310 m, 19 Jan 1973, Madison 1038 (GH); Quispicanchis, entre Abra Walla Walla y Marcapata a 210 km de Cusco, 2800 m, 21 Apr 1988, Núñez V. et al. 8999 (F, MO); Quispicanchis, Marcapata, Checta cuchi, 4250 m, 11 Dec 1938, Vargas 1361 (F); Quispichanchis, Marcapata, Ccompi-pampa, on the grade from Huaillai to Hualla-hualla, 4100 m, 11 Dec 1938, Vargas 9716 (F, K); Paucartambo, Escalerayoc, Dist. Marcachea, 3800 m, 31 Jul 1939, Vargas 11178 (F); Puno: Carabaya, Macusani, 1854, Lechler 2685 (K).

Figures

Figure 63. Solanum macbridei Hunz. & Lallana. (A-C drawn from Solomon & Stein 11660). Reproduced from Knapp (1989) with permission of the Natural History Museum Botany Library. Illustration by Margaret Tebbs.

Figure 64. Distribution of Solanum macbridei Hunz. & Lallana.