Solanum graciliflorum Dunal, Encycl. [J. Lamarck & al.] Suppl. 3: 763. 1814.

Aubriot, Xavier & Knapp, Sandra, 2022, A revision of the " spiny solanums " of Tropical Asia (Solanum, the Leptostemonum Clade, Solanaceae), PhytoKeys 198, pp. 1-270 : 1

16. Solanum graciliflorum Dunal, Encycl. [J. Lamarck & al.] Suppl. 3: 763. 1814.

Fig. 27

Solanum athroanthum Dunal, Prodr. [A. P. de Candolle] 13(1): 208. 1852. Type. Indonesia. Java: [Prov. Banjinwanyne] "in sylvis prope Sukaradja" [Sukaraja], 1846, H. Zollinger 2907 (holotype: G-DC [G00145833]; isotypes: BM [BM000778325], G [G00301684, G003043306], MPU [MPU012648], P [P00368939, P00368940, P00368941]).

Type.

Based on an unpublished illustration of Leschenault collection kept in the Node-Véran collection in Montpellier (lectotype, designated by Aubriot et al. 2016b, pg. 100: Sol. Tab. 47 [MPU028534]).

Description.

Scandent shrub to 2 m tall, armed. Stems apparently erect to decumbent, prickly and very sparsely stellate-pubescent; prickles to 7 mm long, to 8 mm wide at the base, curved, deltate, laterally flattened, pale yellow, glabrous; trichomes porrect-stellate, sessile to subsessile, the rays (4-)5-8, 0.1-0.25 mm long, the midpoints to 0.15 mm long; new growth sparsely stellate-pubescent; bark of older stems dark brownish grey, glabrescent. Sympodial units difoliate, the leaves geminate, usually similar in size. Leaves simple, more or less deeply lobed, the blades (4.5-)7-11 cm long, (1.5-)3-5 cm wide, ca. 2 times longer than wide, elliptic to ovate, chartaceous, slightly discolorous, usually prickly with 1-10(-12) prickles per leaf side, mostly along the midvein, to 9 mm long, to 2 mm wide at the base, straight or slightly curved at the tip, awl-shaped, conical, pale yellow, glabrous; adaxial and abaxial surfaces sparsely to very sparsely stellate-pubescent with sessile to subsessile porrect-stellate trichomes, the rays 6-8, 0.1-0.25 mm long, the midpoint to 0.25 mm long, usually as long as the rays; major veins 3-4 pairs drying dark; base attenuate to truncate; margins shallowly to deeply lobed, the lobes 1-3 on each side, 0.5-2.5 cm long, broadly deltate, apically rounded, the sinuses extending up to 2/3 to the midrib; apex rounded to acute; petiole 0.5-1.8 cm long, 1/10-1/6 of the leaf blade length, unarmed or prickly with 1-2 prickles like those of the blades, sparsely stellate-pubescent with porrect, subsessile trichomes denser at the very base. Inflorescences 2-4 cm long, leaf-opposed or apparently lateral and borne between leaf pairs, unbranched to up to 6 times branched, with 15-50+ flowers, many flowers open at any one time, sparsely to very sparsely stellate-pubescent with trichomes like those of the stems, unarmed; peduncle 1-2(-2.5) cm long, with 0-1 prickles like those of the leaves and stems; pedicels 4-7 mm long, ca. 0.5 mm in diameter at the base, ca. 1 mm in diameter at the apex, erect, unarmed and very sparsely stellate-pubescent with trichomes like those of the stems, articulated at the base; pedicel scars spaced 1-5 mm apart. Buds ellipsoid, strongly exserted from the calyx before anthesis. Flowers 5-merous, apparently all perfect. Calyx with the tube 1-1.5 mm long, campanulate, the lobes 0.25-0.75 mm long, 0.25-0.75 mm wide, deltate, apically acute, unarmed and pubescent abaxially with sessile porrect-stellate trichomes like those of the stems. Corolla 0.5-1 cm in diameter, white to pale lilac, stellate, lobed nearly to the base, the lobes 4-5 mm long, ca. 1 mm wide, narrowly deltate to linear, reflexed at anthesis, glabrous adaxially, densely stellate-pubescent abaxially with sessile porrect trichomes where exposed in bud. Stamens slightly unequal; anthers unequal, three of the five 4.5-5 mm long and two 3-4 mm long, all 0.5-0.75 mm wide, somewhat connivent, tapering, yellow, glabrous, poricidal at the tips, the pores not elongating to slits with drying; filament tube <0.5 mm long, glabrous; free portion of the filaments almost equal, 0.5-1.25 mm long, glabrous. Ovary conical, minutely glandular-puberulent; style ca. 5.5 mm long, slender, curved at the apex, glabrous; stigma capitate, the surfaces minutely papillate. Fruit a globose berry, several to many per infructescence, 0.3-0.5 cm in diameter, red when mature, the pericarp shiny, glabrous; fruiting pedicels 0.8-1.2 cm long, ca. 0.5 mm in diameter at the base, tapering to a slightly enlarged apex, 0.75-1 mm in diameter at the apex, somewhat woody, spreading, unarmed; fruiting calyx lobes slightly expanding to 1.5 mm long, ca. 1/5 the length of the mature fruit, deltate to lanceolate, unarmed. Seeds 6-9 per berry, 3.5-4 mm long, 3-3.5 mm wide, flattened-reniform, orange-brown, the surface minutely pitted, the testal cells pentagonal in outline. Chromosome number: not known.

Distribution

(Fig. 28 ). Solanum graciliflorum is known from only a few collections from the islands of Java, Bali, Sulawesi and Ambon (Indonesia).

Ecology and habitat.

Solanum graciliflorum is a plant of tropical rainforest understory; elevation not recorded.

Common names and uses.

None recorded.

Preliminary conservation status

( IUCN 2019). Near Threatened (NT). EOO (131,936 km2); AOO (16 km2). Solanum graciliflorum is known only from seven collections, several of which are of uncertain localities. It has not been re-collected since the first half of the 20th century, indicating it is certainly of conservation concern, thus we suggest a threat status of Near Threatened to reflect this. Additional collection of this species and exploration of the type locality are priorities.

Discussion.

Solanum graciliflorum is morphologically similar to the sympatric S. cyanocarphium in being a weak, scrambling plant with hooked prickles, but differs from it in its branched inflorescences, smaller flowers and fruits and calyx that is not accrescent in fruit. The inflorescence of S. cyanocarphium is unbranched and the calyx strongly accrescent and covers the berry in fruit.

Aubriot et al. (2016b) superfluously lectotypified S. athroanthum with the specimen in G-DC (G00145833) but Dunal (1852) clearly cited only this specimen in the protologue, thus making it the holotype.

Specimens examined.

See Suppl. materials 1-3.

Figures

Figure 27. Solanum graciliflorum Dunal Herbarium specimen (epitype) collected in Indonesia (Horsfield s. n., BM 000886121). Photograph credit: CC-BY, © copyright The Trustees of the Natural History Museum, London.

Figure 28. Distribution of S. graciliflorum.