Solanum physalifolium Rusby, Mem. Torrey Bot. Club 6: 88. 1896.

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

40. Solanum physalifolium Rusby, Mem. Torrey Bot. Club 6: 88. 1896.

Figs 4C , 122 , 123

Solanum nitidibaccatum Bitter var. robusticalyx Bitter, Repert. Spec. Nov. Regni Veg. 11: 209. 1912. Type. Bolivia. Cochabamba: Parotani, [2,400 m], 20 Mar 1892. C.E.O. Kuntze s.n. (lectotype, designated by Edmonds 1986, pg. 25: NY [00172105]; isolectotype: US [00027706, acc. # 702148]).

Type.

Bolivia. Cochabamba: vic. Cochabamba, 1891, M. Bang 1159 (lectotype, designated by Edmonds 1986, pg. 25, second step designated here: NY [00172129]; isolectotypes: GH [00077734], K [K001390419], MO [MO-503737, acc. # 5579576], NDG [ NDG45199 ], NY [00172128], PH [00030469], US [00027742, acc. # 1324703; 00650472, acc. # 3412820], WIS [v0256203WIS]).

Description.

Annual herbs to 0.5 m high, spreading to 1 m in diameter, from a strong taproot and occasionally somewhat woody at the base. Stems terete or occasionally winged from decurrent leaf bases, the wings if present to 1.5 mm wide, densely glandular-pubescent with transparent 6-10-celled simple uniseriate trichomes to 2 mm long, but most shorter than 2 mm, later glabrescent; new growth densely glandular-pubescent with transparent simple uniseriate trichomes like the young stems, the longest trichomes ca. 2 mm long; bark of older stems pale brown, glabrescent. Sympodial units difoliate or trifoliate, the leaves not usually geminate. Leaves simple, entire or shallowly toothed, the blades (1.4)2-6 cm long, (0.8)1.4-3.2 cm wide, ovate to elliptic-ovate, widest in the lower third, membranous, concolorous; adaxial surface sparsely to moderately and evenly glandular-pubescent with transparent 6-10-celled simple uniseriate trichomes 1.5-2 mm long; abaxial surfaces glandular-pubescent like the upper surfaces, but the trichomes denser along the veins; principal veins 3-5 pairs, drying somewhat yellowish green; base abruptly truncate then attenuate onto the petiole; margins entire to shallowly toothed, the teeth ca. 1.5 mm long, deltate with acute tips; apex acute; petiole 0.3-1.5 cm long, winged from the decurrent leaf bases. Inflorescences internodal or occasionally opposite the leaves, unbranched, 0.8-2.1 cm long, with 3-6 flowers clustered at the tips and the inflorescence more or less subumbellate, densely glandular-pubescent like the stems; peduncle 0.7-1.7 cm long; pedicels 0.6-0.8 cm long, ca. 0.25 mm in diameter at the base, ca. 0.5 mm in diameter at the apex, filiform, spreading at anthesis, glandular-pubescent like the rest of the inflorescence, articulated at the base; pedicel scars 0.5-3 mm apart, the lowermost flower more distant from the rest. Buds ellipsoid, the corolla just exserted from the calyx lobe tips before anthesis. Flowers 5-merous, cosexual (hermaphroditic). Calyx tube 1-1.2 mm long, conical, the lobes 1.5-2 mm long, 1-1.5 mm wide, triangular with slightly rounded tips, densely glandular-pubescent with simple uniseriate trichomes like those of the stems. Corolla 0.8-1 cm in diameter, white with a green central eye, stellate, lobed ca. 1/2 way to the base, the lobes 3-3.5 mm wide, 2.5-3 mm wide, broadly triangular to deltate, spreading to slightly reflexed at anthesis, adaxially glabrous, abaxially densely papillate at the tips and margins and with long transparent trichomes at tips and along the midvein, these a mixture of glandular and eglandular. Stamens equal; filament tube ca. 0.3 mm long; free portion of the filaments 1-1.2 mm long, adaxially pubescent with tangled eglandular simple uniseriate trichomes; anthers 2-3 mm long, 1-1.1 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age. Ovary conical, glabrous; style 3.5-5 mm long, strongly hooked in the distal part, exserted beyond the anther cone, densely papillate in the lower half to 3/4 where enclosed in the anther cone; stigma capitate, the surface minutely papillate. Fruit a globose berry, 0.8-1 cm in diameter, green and strongly marbled with white when mature, the pericarp thin, shiny and translucent, glabrous; fruiting pedicels 0.8-1.2 cm long, ca. 0.75 mm in diameter at the base, not markedly woody, strongly deflexed at the base, not persistent; fruiting calyx accrescent and spreading, not enclosing or appressed to the berry, the tube 3.5-5.5 mm long, the lobes ca. 5.5 mm wide, 4.5-5.5 mm wide, the venation prominent in dry specimens. Seeds 30-40 per berry, ca. 2 mm long, ca. 1.5 mm wide, flattened and teardrop shaped, reddish brown, the surfaces minutely pitted, the testal cells rectangular in shape. Stone cells absent or present and 2 at the apex of the berry or 6 with 2 apical and 4 equatorially positioned, ca. 0.5 mm in diameter, creamy white. Chromosome number: not known.

Distribution

(Fig. 124 ). Solanum physalifolium is an Andean species, occurring from southern Peru (Depts. Apurímac, Cusco) through Bolivia (Depts. Chuquisaca, Cochabamba, La Paz, Potosí, Santa Cruz, Tarija) to northern Argentina (Provs. Catamarca, Jujuy, Salta).

Ecology and habitat.

Solanum physalifolium grows in dry interAndean valleys, often along streams or in the shade of small trees, from 1,500 to 3,500 m elevation.

Common names and uses.

None recorded.

Preliminary conservation status

( IUCN 2022). Least Concern [LC]. EOO = 757,522 km2 [LC]; AOO = 172 km2 [EN]. Solanum physalifolium is a plant of open disturbed areas and has a wide distribution along the Andes. It occurs in protected areas in Argentina (e.g., Parque Nacional Baritú) and Peru (around the ruins of Sacsayhuamán near Cusco).

Discussion.

Solanum physalifolium is one of several glandular-pubescent morelloids from the southern Andes. Morphologically it is similar to both S. physalidicalyx and S. profusum ; the three species all have anthers 2-3 mm long and long, sticky glandular trichomes. Solanum physalifolium differs from S. physalidicalyx in mature fruits; the calyx is inflated and completely covering the whitish green to cream berry in S. physalidicalyx and only partially covering the dark green marbled berry in S. physalifolium . Solanum physalifolium is an annual, while S. profusum is a rhizomatous perennial. 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 can be found in Knapp et al. (2020).

In lectotypifying S. physalifolium Edmonds (1986) only cited “NY” and did not specify which sheet of Bang 1159 she was referring to as the lectotype; we here select the better preserved of the two sheets held at NY (00172129) in a second step lectotypification.

Figures

Figure 4. Representative fruits, seeds and stone cells of South American morelloids A bilobed fruits in S. tripartitum with fully mature red berries at the base of the inflorescence and maturing green, yellow, and orange fruits more distally B orange-red fleshy berries of S. corymbosum in highly branched inflorescences C fully mature marbled fruits in S. physalifolium D immature ellipsoid fruits of S. antisuyo E fully mature fruits of S. antisuyo F immature green fruits amongst fully mature purple-black fruits in S. cochabambense G fully mature fruits of S. polytrichostylum H stone cells (also known as sclerotic granules or brachysclerids) found in the fruits of most species of the Morelloid clade (left side of photo) next to the teardrop shaped seeds (right side of photo; S. umalilaense Manoko) I stone cells visible in dried fruits of herbarium specimens (S. triflorum). (A Barboza 3563 B Saerkinen et al. 4604 B C Knapp et al. 10334 D Gonzales 10256 E Gonzales 10256 F Knapp et al. 10363 G Saerkinen et al. 5277 H Nijmegen accession A 24750133 I Podlech 8624 BM 000848286). Photos by P. Gonzales, S. Knapp, and T. Saerkinen.

Figure 122. Solanum physalifolium A flowering branch B inflorescence C calyx D flower E dissected flower F gynoecium G fruit (A-G Barboza et al. 2229). Illustration by S. Montecchiesi. Previously published in Barboza et al. (2013: 253).

Figure 123. Solanum physalifolium A habit B abaxial surface of flower C flowers and buds D developing fruits (A-D Knapp et al. 10332). Photos by S. Knapp.

Figure 124. Distribution map of Solanum physalifolium.