Solanum profusum C.V.Morton, Revis. Argentine Sp. Solanum 86. 1976.

Knapp, Sandra, Saerkinen, Tiina & Barboza, Gloria E., 2023, A revision of the South American species of the Morelloid clade (Solanum L., Solanaceae), PhytoKeys 231, pp. 1-342 : 1

43. Solanum profusum C.V.Morton, Revis. Argentine Sp. Solanum 86. 1976.

Figs 131 , 132

Type.

Argentina. Jujuy: Dpto. Dr. Manuel Belgrano, near Jujuy, 2 May 1939, E.K. Balls 5915 (holotype: US [00027757, acc. # 1779255]; isotypes: E [E00298913], UC [ UC683471 ]) .

Description.

Prostrate, perennial herb to 0.2 m high, somewhat woody at the base, rooting along the nodes and from rhizomes and forming large populations. Stems terete, sprawling, densely glandular pubescent with transparent 2-3-celled, simple uniseriate trichomes mostly 0.5 mm long, some to 1.5 mm long; new growth densely glandular-pubescent with simple uniseriate trichomes like those of the stems, densely papillate with tiny glandular trichomes on leaf laminar surfaces; bark of older stems greenish brown. Sympodial units difoliate, the leaves not geminate. Leaves simple, entire or occasionally very shallowly toothed, the blades 3-4 cm long, 1.2-1.5 cm wide, narrowly elliptic, widest at the middle, membranous, concolorous; adaxial surfaces sparsely to moderately and evenly glandular-pubescent with 2-3-celled, simple, uniseriate trichomes 1-1.5 mm long, occasionally some shorter; abaxial surfaces similarly glandular-pubescent, but trichomes on the lamina somewhat longer than those on the veins; principal veins 3-4 pairs; base attenuate along entire petiole; margins entire or very shallowly toothed, the teeth if present ca. 1 mm long, very broadly deltate with rounded tips; apex acute, with the ultimate tip usually somewhat rounded; petiole 0.1-0.6 cm long, glandular-pubescent like the stems and leaves. Inflorescences opposite the leaves or internodal, unbranched, 0.6-2.3 cm long, with 3-6 flowers in the distal half, densely glandular-pubescent with transparent, simple uniseriate trichomes like those of the stems; peduncle 0.5-2 cm long; pedicels 0.9-1 cm long, ca. 0.5 mm in diameter at the base, ca. 1.2 mm in diameter at the apex, tapering, densely glandular-pubescent, spreading at anthesis and the flowers nodding, articulated at the base leaving small areas of darker tissue after abscission; pedicel scars irregularly spaced 1.5-2 mm apart. Buds globose to short-ellipsoid, the corolla ca. 1/4 exserted from the calyx lobes before anthesis. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 1.5-2 mm long, conical, the lobes 2.5-3 mm long, 1.5-2 mm wide, lanceolate with the tips acute or slightly rounded, densely glandular-pubescent like the pedicels. Corolla 1.5-1.8 cm in diameter, white or pale lilac (with age) with a green central eye, stellate, lobed halfway to 2/3 of the way to the base, the lobes 5-5.5 mm long, 3.5-4 mm wide, broadly triangular, strongly reflexed at anthesis, glabrous adaxially, densely glandular-pubescent on the midvein, tips and margins abaxially, the trichomes longer at the tips. Stamens equal; filament tube minute; free portion of the filaments 0.5-1 mm long, sparsely pubescent with tangled transparent simple uniseriate trichomes adaxially; anthers 3-3.5 mm long, 1.2-1.5 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age. Ovary conical, glabrous; style 6-6.5 mm long, straight, exserted beyond the anther cone, densely pubescent in the lower third with transparent, eglandular simple uniseriate trichomes; stigma capitate to globose, the surface minutely papillate. Fruit a globose berry, 0.7-0.9 cm in diameter, green or pale green when mature, opaque, the pericarp thin, matte, glabrous; fruiting pedicels ca. 1 cm long, ca. 0.5 mm in diameter at the base, ca. 2 mm in diameter at the apex, not markedly woody, strongly deflexed at the base, not persistent; fruiting calyx accrescent, appressed to the berry, the tube 3.5-5 mm long, the lobes 4-5.5 mm long, 3.5-4 mm wide, enclosing the berry ca. halfway (approximately half of the berry visible beyond the calyx lobes). Seeds ca. 20 per berry, ca. 1.5 mm long, ca. 1.2 mm wide, flattened and teardrop shaped, tan to reddish gold, the surfaces minutely pitted, the testal cells rectangular-pentagonal, those near the margins longer and thinner. Stone cells absent. Chromosome number: not known.

Distribution

(Fig. 133 ). Solanum profusum is endemic to the Andes of northern Argentina (Provs. Jujuy, Salta).

Ecology and habitat.

Solanum profusum is a plant of open rocky areas along streams or grasslands with patches of semideciduous forest, from 1,200 to 1,500 m elevation.

Common names and uses.

None recorded.

Preliminary conservation status

( IUCN 2022). Endangered [EN, B1, 2 a,b(ii)]. EOO = 4,852 km2 [EN]; AOO = 28 km2 [EN]. Solanum profusum is known from only four sites (some of these with imprecise localities) and has a narrow geographic range. Some of its populations occur very near to the expanding urbanisation of Salta; subsequent searches for plants in historical collecting sites have been unsuccessful. Solanum profusum may be more resilient to disturbance than we think though, as it is rhizomatous and is able to spread vegetatively; this, however, does not assist with genetic diversity. Solanum profusum does not occur in any protected areas.

Discussion.

Solanum profusum is one of several glandular-pubescent species of morelloids with accrescent to somewhat accrescent calyces occurring in north-central Argentina (e.g., S. physalidicalyx , S. physalifolium , S. tweedieanum ). Solanum profusum differs from S. physalidicalyx and S. tweedieanum in lacking a strongly accrescent calyx that completely covers the mature berry. It has narrower, less incised leaves than either of those two species and has shorter anthers than S. tweedieanum (3-3.5 mm long versus 4-6 mm long). Plants in flower can be difficult to identify. Solanum profusum does not overlap in distribution with S. physalifolium , whose berries are not consistently covered by an accrescent calyx. Solanum profusum is a rhizomatous perennial and possibly clonal, while S. physalifolium is an annual. Leaf shape also differs, S. profusum has more lanceolate to lance-elliptic leaves, while those of S. physalifolium and S. physalidicalyx are ovate to elliptic ovate. The distributions of the three species do not overlap. A key to the glandular-pubescent morelloids in Argentina can be found in Knapp et al. (2020).

Figures

Figure 131. Solanum profusum A habit B flowering branch C flower bud D flower E calyx F glandular trichome of the calyx G dissected flower H stamen, dorsal view I stamen, ventral view J glandular trichome of the filament K gynoecium L eglandular trichome of the style (A-L Balls 5915). Illustration by P. Peralta. Previously published in Barboza et al. (2013: 255).

Figure 132. Solanum profusum A habit B underground rhizome C flowering branch D inflorescence with flowers at full anthesi E infructescence with maturing fruits F developing fruit inside the enlarged calyx (A-F Barboza 4928). Photos by G. E. Barboza.

Figure 133. Distribution map of Solanum profusum.