Solanum stagnale Moric.

Knapp, Sandra, Gouvêa, Yuri F. & Giacomin, Leandro L., 2025, A revision of the endemic Brazilian Solanum hexandrum group (Leptostemonum, Solanum, Solanaceae), PhytoKeys 253, pp. 199-259 : 199-259

5. Solanum stagnale Moric. , Pl. Nouv. Amer. 34, tab. 23. 1837.

Fig. 11

Solanum moricandii Dunal , Prodr. [A. P. de Candolle] 13 (1): 319. 1852, nom. illeg. superfl. Type: Based on Solanum stagnale Moric.

Solanum moricandii Dunal var. majus Dunal , Prodr. [A. P. de Candolle] 13 (1): 319. 1852. Type: Based on Solanum stagnale Moric.

Solanum moricandii Dunal var. minus Dunal , Prodr. [A. P. de Candolle] 13 (1): 320. 1852. Type; Brazil. Bahia: Ilheus, 1840, J. S. Blanchet 3095 A (lectotype, designated by Whalen et al. (1981), pg. 69: G-DC [G 00131269]; isolectotypes: G [G 00343734], P [P 00371688], W [acc. # 0004133]).

Solanum moricandii Dunal var. echinocalyx Dunal , Prodr. [A. P. de Candolle] 13 (1): 320. 1852. Type: Brazil. Sin. loc., J. J. Lalande s. n. (holotype: P [P 00371692]).

Solanum nolitangere Salzm. ex Dunal , Prodr. [A. P. de Candolle] 13 (1): 320. 1852. Type: Brazil. Bahia: “ in maritimis ”, 1830, P. Salzmann s. n. (lectotype, designated by Whalen et al. (1981), pg. 69: G-DC [G 00131246]; isolectotypes: C [C 10019308], K [K 000590187, K 000590188], LE [LE 00016989], P [P 00366831, P 00366832, P 00366833, P 00366834], W [acc. # 1889-0293774]).

Solanum nolitangere Dunal var. ochraceo-ferrugineum Dunal , Prodr. [A. P. de Candolle] 13 (1): 320. 1852. Type: Brazil. Bahia: sin. loc., 1832, J. S. Blanchet 710 (lectotype, designated by Whalen et al. (1981), pg. 69: G-DC [G 00131245]).

Type.

Brazil. Bahia: sin. loc., J. S. Blanchet 2085 (lectotype, designated by Whalen et al. (1981), pg. 69 [as holotype]: G [ G 00343733 ]; isolectotypes: BM [ BM 000617832 ], G-DC [ G 00131205 ], P [ P 00371689 , P 00578808 , P 00371690 ]) .

Description.

Large, soft-wooded perennials 0.3 - several m tall. Stems terete, usually somewhat winged from the decurrent leaf bases, densely pubescent and sparsely prickly, the pubescence of whitish or reddish-cream porrect-stellate or occasionally multangulate (Agra 617) trichomes with multiseriate stalks 0.2–0.8 (- 2.5) mm long, the lateral rays 4–9, 0.4–0.6 (- 1) mm long, the mid-points much shorter than the rays, 0.05–0.2 mm long, the hairs densely interwoven and entirely concealing young stems, the prickles 1–2 cm long, 0.3–0.5 cm wide at the base, straight or recurved (e. g. Blanchet 2085) broad-based and strongly laterally compressed, often densely stellate-pubescent basally. Sympodial units difoliate, the leaves of a pair not geminate. Leaves shallowly lobed and coarsely repand; blades 9.5–30 cm long, 8–15 cm wide, ca. 1–1.5 times as long as wide, broadly elliptic to ovate, slightly discolorous, membranous or somewhat chartaceous, prickly on both surfaces along the veins with straight prickles to 15 mm long; adaxial surfaces densely pubescent with eglandular short- to long-stalked porrect stellate trichomes, the stalks 0.5–0.8 (- 1) mm long, the rays 4–8, 0.5–0.7 mm long, the mid-points minute or equal in length to the rays, the lamina visible under the microscope; abaxial surfaces densely woolly-pubescent with stalked porrect stellate trichomes, the stalks 0.5–1 mm long, the rays 6–10, 0.5–1 mm long, often not in a single plane, the mid-points 0.2–0.4 mm long, much shorter than the rays; principal veins 4–5 pairs, with scattered straight prickles to 1.3 mm long, the prickles longer and larger on the mid-rib; base strongly decurrent along a winged petiole, the wing of laminar tissue to 0.5 cm wide on each side, often decurrent on to stem; margin lobed, the lobes 4–5, 1.5–3 cm long, 2–3 cm wide, deltate, acute- or round-tipped, often with irregular secondary lobing, the sinuses reaching less than halfway to the mid-rib; apex acute or obtuse; petioles 0.8–5 cm, usually 1 / 4–1 / 3 the length of the blades and winged, stellate-pubescent like the stems, prickly. Inflorescences 2–7 cm long, extra-axillary or leaf-opposed, unbranched, with ca. 10 flowers, the axes densely stellate-pubescent, unarmed; peduncle 1–2 cm; pedicels 2–5 mm, 1–2.5 mm in diameter at the base, 2–2.6 mm diameter at the apex, articulated at the base; pedicel scars closely spaced 2–7 mm apart. Flowers 5 - merous, heterostylous, with the lowermost long-styled (co-sexual) and the distalmost short-styled (functionally staminate), the plants probably andromonecious. Calyx with the tube 5–10 mm long, 8–10 mm in diameter, broadly obconical, the lobes 10–15 mm long, 5–8 mm wide, ovate-lanceolate or somewhat spathulate or tongue-shaped, obtuse or round apically, densely stellate-pubescent on both surfaces, often with scattered prickles on both surfaces near the mid-vein, often purple-tinged distally. Corolla 2.5–4.5 cm in diameter, white or lilac with a paler central star, stellate, lobed 2 / 3 to 3 / 4 of the way to the base, interpetalar tissue a thin edge on the lobes, the lobes 13 - 20 mm long, 10–12 mm wide, ovate-lanceolate, densely stellate-pubescent abaxially, the trichomes with robust mid-points equal to or longer than the rays, glabrous adaxially, but the acute tips stellate-pubescent, the interpetalar tissue thin, glabrous. Stamens equal; filament tube minute; free portion of the filaments ca. 1 mm long, glabrous; anthers 7–10 mm long, ca. 3 mm wide, broadly lanceolate and tapering, connivent, glabrous, yellow, abaxially swollen in the lower half (gibbous) and somewhat papillate, poricidal at the tips, the pores directed distally, slightly extrorse, not elongating to slits with age. Ovary conical, densely stellate-pubescent, the trichomes with well-developed lateral rays; style 10–14 mm long, glabrous or sparsely stellate-pubescent in the lower half; stigma large and capitate. Fruit a globose to flattened-globose berry, 2–2.5 cm in diameter, whitish-green at maturity, sparsely stellate-pubescent, ultimately glabrous, the pericarp matte or slightly shiny; fruiting pedicels 0.5–1 cm long, usually less than 0.5 cm long, 3–5 mm in diameter at the base, ca. 6 mm in diameter at the apex; fruiting calyx only partially accrescent, tightly investing. but not completely covering fruit, the tube ca. 1.5 cm long, the lobes ca. 15–20 mm long, ca. 10 mm wide, not overlapping. Seeds ca. 100 per berry, ca. 2.5 mm long, ca. 1.5 mm wide, flattened reniform, dark brown, the surfaces minutely pitted, the testal cells pentagonal in outline. Chromosome number; 2 n = 24 ( Bernardello et al. 1994; voucher (grown in Indiana and, therefore, should be in IND, but not seen) Carvahlo 3213, possibly a misprint for Carvalho 3219).

Distribution

(Fig. 12 ). Solanum stagnale is endemic to eastern Brazil; it has been recorded from the States of Bahia and adjacent northern Minas Gerais and disjunctly in Paraíba State. This disjunct distribution is unusual, the single collection from Paraíba is from the northern side of the São Franscisco River, the site of the Pernambuco area of endemism.

Ecology and habitat.

Solanum stagnale occurs in sandy coastal vegetation (restinga) habitat, in sand dunes, forests, forest edges and somewhat open habitats, from sea level to 300 m elevation.

Common names and uses.

None recorded.

Preliminary conservation status

( IUCN 2020). EOO (157,059 km 2, LC); AOO (68 km 2, EN). Solanum stagnale is known from more than five localities, even if the widely disjunct collection from Paraíba State is not included. Only one of these is within a protected area (Estação Ecológica de Cotegipe in Mun. Salvador, Bahia). The fragmented nature of the habitat and the absence of state or national level of protection for areas where it occurs suggests it should be assigned a preliminary conservation status of Vulnerable, based on criteria B 2 a, b i, ii, iii, iv.

Discussion.

Like all members of this group, S. stagnale has large, repand leaves. Most collections have strongly winged petioles with a wing extending fully to the base, but occasionally the wing becomes very narrow basally (Rosas 1 from Salvador). The pedicels in both flower and fruit of S. stagnale are the shortest in the group, rarely reaching 5 mm long. Solanum stagnale is easily distinguished from S. hexandrum , with which it is most similar, by its pubescence of porrect-stellate trichome with usually more than 5 lateral rays, usually curved prickles, short, stubby pedicels usually less than 0.5 cm long, spathulate calyx lobes with rounded apices and berry that is not completely enclosed in an accrescent calyx. The trichomes of S. stagnale usually have mid-points that are shorter than or equal to the rays in length; in contrast, other species of the group have longer mid-points.

Whalen et al. (1981) treated S. stagnale as a member, albeit anomalous, of section Lasiocarpa (Dunal) D’Arcy and Whalen (1984) later included it in his equivalent S. quitoense Lam. species group. Both groups were composed of species, with the exception of S. stagnale , which are now recognised ( Gagnon et al. 2022) as the Lasiocarpa clade; they share with members of the S. hexandrum group large repand leaves. Molecular data ( Gouvêa 2020; Gagnon et al. 2022), however, clearly show that S. stagnale is related to S. hexandrum and other Brazilian endemic species of this group, not to the largely Andean members of the Lasiocarpa clade.

Dunal (1852) changed the name S. stagnale to S. moricandii because he felt it was inappropriate (“ Blanchet in schedis non dicit hanc specimen crescere in stagnis, ut putat Moricand, et hâc ratione, nomen stagnale mutavi ” – Blanchet does not say this specimen grows in ponds, as Moricand thinks, for this reason I have changed the name stagnale ”: Dunal 1852: 319) rendering the name S. moricandii illegitimate and superfluous.

Figures

Figure 11. Solanum stagnale A habit of a young plant B habit of an older reproductive plant B, C inflorescence congested with flowers clustered due to extremely short pedicels D flower buds and short-styled flower (arrows point to spathulate calyx lobes) E long-styled flower and leaf base markedly decurrent on to the petiole F berries (almost mature) with appressed, only partially accrescent fruiting calyces (A, D Giacomin & Stehmann 1930, BHCB; B, C, E, F unvouchered field photograph, Bahia State [12 ° 32 ' 23 " S, 38 ° 03 ' 08 " W]). Photos: A, D Leandro L. Giacomin B, C, E, F Wagner Nogueira.

Figure 12. Distribution of S. stagnale.