Solanum, (G. Don) Walp., Repert. Bot. Syst.

Wahlert, Gregory A., Chiarini, Franco E. & Bohs, Lynn, 2015, A Revision of Solanum Section Lathyrocarpum (the Carolinense Clade, Solanaceae), Systematic Botany 40 (3), pp. 853-887 : 861-862

SOLANUM SECT. LATHYROCARPUM (G. Don) Walp., Repert. Bot. Syst. 3: 88. 1844.

— TYPE: Based on Solanum subsect. Lathyrocarpum G. Don.

Solanum subsect. Lathyrocarpum G. Don, Gen. Hist. 4: 436. 1838.—

LECTOTYPE SPECIES: Solanum carolinense L., designated by D’ Arcy, Ann. Missouri Bot. Gard. 59: 270. 1972.

Solanum subsect. Asterotrichotum Dunal, Prodr . 13: 30, 282. 1852.—

LECTOTYPE SPECIES: Solanum carolinense L., designated by D’ Arcy, Ann. Missouri Bot. Gard. 59: 267. 1972.

Erect to decumbent or sprawling perennial herbs up to 1.2 m tall; stems unbranched or branched near the base, sometimes rooting at the nodes; roots often with a rhizomatous habit and spreading horizontally, sometimes with tuberlike swellings. Stems glabrescent to densely stellate-pubescent with translucent, white, light brown, or golden hairs, the stellae sessile to stalked, 0.2–1.8 mm in diameter, with 4–10 lateral rays, the central ray absent or 1–5-celled and up to 3 mm long, unarmed or sparsely to densely armed with straight or slightly recurved yellow-brown tapered prickles up to 7 mm long, these rarely minutely glandular-pubescent. Sympodial units 2- to 3-foliate, sometimes plurifoliate, the leaves not geminate. Leaves simple, the blades 1.8–22 × 1–18 cm, ovate, elliptic or lanceolate in outline, somewhat discolorous, sparsely to densely stellate-pubescent abaxially and adaxially, the stellae sessile to short-stalked, 0.6–1.2 mm in diameter, with 4–6 lateral rays, the central ray 1–2-celled and up to 1.7 mm long, unarmed or sparsely to moderately armed with prickles up to 9 mm long on the major veins abaxially and adaxially; base cuneate, cordate or truncate, equal to unequal; margin subentire, sinuate or lobed with 1–6 lobes per side, sometimes very deeply lobed almost to the midrib; apex acute, obtuse or rounded; petioles 0.4–7 cm, sparsely to densely stellate-pubescent with hairs like those of the stem, unarmed or sparsely to moderately armed with prickles up to 12 mm long. Inflorescences 1–15 cm long, extra-axillary, unbranched or branched, with 1–20 flowers, the plants weakly andromonoecious, the axes sparsely to densely stellate-pubescent, unarmed or sparsely armed with prickles up to 5.4 mm long; peduncle up to 8 cm long; pedicels 0.5–5.5 cm in flower, 1–5.5 cm long and curved downward in fruit, spaced 0.5–2.5 cm apart, weakly articulated at the base, sparsely to densely stellate-pubescent, unarmed or sparsely armed with prickles up to 5.5 mm long. Flowers 5-merous. Calyx 4.5–14 mm long, the tube 1–5 mm long, the lobes 2.5–10 × 1.5–5 mm, narrowly or broadly ovatelanceolate to triangular, the apex acute to acuminate, moderately to densely stellate-pubescent abaxially, glabrous adaxially, unarmed or sparsely to densely armed with prickles up to 5.5 mm long; fruiting calyx spreading to reflexed and weakly to strongly accrescent, sometimes completely covering the fruit, 7–20 mm long, the tube 0.2–5 mm long, the lobes 4–15 × 1.5–8 mm, narrowly triangular to ovate-lanceolate, sparsely to moderately stellate-pubescent, unarmed or sparsely to moderately armed with prickles up to 5 mm long. Corollas 1.2–4.6 cm in diameter, 8–25 mm long, stellate to stellatepentagonal or rotate-stellate, chartaceous, white, pale blue, or lavender-violet, the tube 2–15 mm long, the lobes 2–17 × 4–15 mm, deltate to triangular, the apex acute to apiculate, moderately to densely stellate-pubescent abaxially, glabrous or very sparsely stellate-pubescent adaxially. Stamens with filaments 0.6–3 × 0.15–0.6 mm; anthers 3.5–10 × 0.6–2.2 mm, narrowly lanceolate, weakly or not connivent, yellow, the pores directed distally. Ovary 1–3.2 × 0.5–2.5 mm, subglobose to ovoid, glabrous or sometimes sparsely to moderately glandular-pubescent, rarely moderately pubescent with white stellate or simple hairs; style 7–15 × 0.2–1.5 mm, cylindrical, straight, glabrous or rarely sparsely glandular-pubescent at the base, rarely moderately pubescent with stellate or simple hairs, exserted in hermaphroditic flowers; stigma capitate. Fruits 0.8–2.2 × 0.7–2.5 cm, ovoid, globose or depressedglobose, the apex rounded, light green with darker green mottling or pale greenish-white when young, yellow to yellow-orange at maturity, glabrous, the rind tough. Seeds 1.5–3.5 × 1.1–3 mm, flattened-reniform, lenticular, yellow, the surface finely foveolate.

KEY TO THE SPECIES OF SOLANUM SECT. LATHYROCARPUM

1. Stems and petioles stellate-pubescent with the central ray 1-celled and less than or equal to the length of the lateral rays or with simple hairs in one species...................................................................................... 2

2. Plants decumbent, creeping along the ground, sometimes rooting at the nodes................................................. 3

3. Stems glabrous or very sparsely pubescent with simple hairs and sparsely armed with prickles; Bolivia................ 8. S. moxosense

3. Stems moderately to densely pubescent with stellate hairs and moderately to densely armed with prickles; southeastern Brazil............................................................................................ 4

4. Stems, leaves, inflorescence axes, and calyces moderately pubescent with sessile to short-stalked stellate hairs, the stalks minute, up to 0.2 mm long; calyx unarmed to sparsely armed with prickles.......................... 5. S. flagellare

4. Stems, leaves, inflorescence axes, and calyces moderately to densely pubescent with sessile to long-stalked stellate hairs, the stalks often stout and prickle-like, up to 2 mm long; calyx moderately to densely armed with prickles..... 11. S. reineckii

2. Plants upright, not rooting at the nodes................................................................................ 5

5. Leaf blades 6–15 × 3–10 cm; inflorescence 2- to several-branched, with up to ca. 20 flowers per inflorescence; North America.................................................................................... 4. S. dimidiatum

5. Leaf blades 1.8–10 × 1–5 cm; inflorescence unbranched or once branched, with up to ca. 6 flowers per inflorescence; South America............................................................................................... 6

6. Stem, petioles, leaf blades, inflorescence axes, pedicels, and calyces unarmed or sparsely armed with prickles; leaf blades 2–10 × 1–5 cm ........................................................................... 1. S. aridum

6. Stem, petioles, leaf blades, inflorescence axes, pedicels, and calyces moderately to densely armed with prickles; leaf blades 1.8–5.5 × 1–2.5 cm ....................................................................... 7. S. juvenale

1. Stems and petioles stellate-pubescent with the central ray 1–5-celled and longer than the length of the lateral rays, simple hairs absent.................................................................................................. 7

7. Calyces pubescent with few to many stellate hairs bearing stout prickle-like stalks up to 6 mm long; South America................... 8

8. Corollas light blue; fruits 0.8–1 × 0.7–1.3 cm, globose, completely covered by the accrescent fruiting calyx; stems, petioles, leaf blades, inflorescence axes, and pedicels sparsely to moderately armed with prickles; calyces densely armed......... 3. S. comptum

8. Corollas white; fruits 1.5–2.2 × 1–2 cm, depressed globose, with only the basal portion covered by the weakly accrescent fruiting calyx; stems, petioles, leaf blades, inflorescence axes, and pedicels unarmed or rarely sparsely armed with prickles; calyces unarmed or sparsely armed................................................... 6. S. hieronymi

7. Calyces pubescent with the stellate hairs sessile or with stalks up to 0.5 mm long; North America.................................. 9

9. Plants up to 0.2 m tall; leaf margins entire, sinuate to weakly lobed; inflorescence with up to ca. 4 flowers.............. 10. S. pumilum

9. Plants up to 1.2 m tall; leaf margins weakly to deeply lobed; inflorescence with up to ca. 15 flowers............................. 10

10. Stems unarmed or sparsely armed with prickles up to 6 mm long; inflorescences unbranched or once branched; corollas 2.2–3 cm in diameter; central and southeastern U. S. A., locally naturalized worldwide................ 2. S. carolinense

10. Stems sparsely to moderately armed with prickles up to 12 mm long; inflorescences 2- to several-branched; corollas 2–4.4 cm in diameter; mainly Alabama, Florida, and Georgia, rarely in Mississippi ..................... 9. S. perplexum