Solanum species of eastern and northern Australia
Habit. Erect, rhizomatous perennial shrub, 0.4–1 m high. Large stems bark thin, nondescript or furrowed, corky throughout.
Branchlets. Branchlets yellow or rusty or brown. Branchlet prickles 40–260 per decimetre, straight, acicular, 2.5–8 mm long, 9–17 times longer than wide, with scattered stellate hairs on lower half. Branchlet hairs stellate. Branchlet stellae very dense, 0.4–0.8 mm diameter, stalks 0–0.5 mm long. Branchlet stellae lateral rays 7–9, porrect or ascending. Branchlet stellae central ray 0.7–1.6 times as long as laterals, not gland-tipped, thready. Branchlet Type 2 hairs absent.
Leaves. Leaves lanceolate or elliptical or ovate, entire or shallowly lobed throughout. Leaf lobes 0 on each side or 3–5 on each side, obtuse, lobing index 1–2. Leaves 3.9–13.2 cm long, 1.8–5.1 cm wide, 1.8–2.4 times longer than broad. Leaf apex obtuse or acute, base cuneate or obtuse. Leaf oblique part 2–12 mm long, obliqueness index 2–11 percent. Petioles 1.2–4.3 cm long, 16–38% length of lamina, prickles present.
Upper leaf surface. Upper leaf surface grey-green or grey. Upper leaf surface prickles absent or present on midvein only, 0–1, straight, acicular, 2–4 mm long. Upper leaf surface stellate hairs distributed throughout, protostellae absent, hair density dense to very dense. Upper leaf surface stellae 0.05–0.1 mm apart, 0.6–0.8 mm across, stalks 0.1–0.2 mm long. Upper leaf surface stellae lateral rays 7–8, porrect. Upper leaf surface stellae central ray 0.8–1.5 times as long as laterals, not gland-tipped. Upper leaf surface simple hairs absent. Upper leaf surface Type 2 hairs absent.
Lower leaf surface. Lower leaf surface greenish-white or white, grey or yellowish. Lower leaf surface prickles absent or present on midvein only, 0–2, straight, acicular. Lower leaf surface stellate hair density very dense. Lower leaf surface stellae 0.05–0.1 mm apart, 0.6–0.8 mm diameter, stalks 0.1–0.4 mm long. Lower leaf surface stellae lateral rays 7–8, porrect. Lower leaf surface stellae central ray 0.7–1.5 times as long as laterals, not gland-tipped. Lower leaf surface simple hairs absent. Lower leaf surface Type 2 hairs absent.
Inflorescence. Inflorescence leaf-opposed or supra-axillary, cymose (pseudo-racemose). Inflorescence common peduncle absent or present, 0–33 mm long. Inflorescence rachis prickles absent or present. Inflorescence 15–30-flowered, with one bisexual flower, the rest male. Flowers 5-merous, markedly dimorphic, with larger pricklier basal flower(s). Pedicels at anthesis 5–27 mm long, same thickness throughout, prickles absent or present. Calyx prickles on basal bisexual flowers 90–130, 3–9 mm long. Calyx prickles on distal male flowers 0–12, 2–2.5 mm long. Calyx tube at anthesis 2–6 mm long. Calyx lobes at anthesis deltate or attenuate, 8–21 mm long. Calyx prickles at anthesis absent or present, 0–130 per flower, 2–9 mm long. Calyx stellae very dense, white or transparent, 0.5–0.8 mm across, stalks 0–0.8 mm long, lateral rays 7–9. Calyx stellae central ray 1–1.5 times as long as laterals, not gland-tipped. Calyx simple hairs absent, Type 2 hairs absent. Corolla purple, 7–23 mm long, rotate or shallowly lobed, inner surface glabrous or sparsely stellate-hairy. Anthers 5–7 mm long. Filaments 0.5–1 mm long. Ovary glabrous or with stellate hairs only. Functional style 12 mm long, erect near base, then bent, displacing one anther, with stellate hairs only.
Fruits. Fruiting calyx lobes more than half length of mature fruit, prickles 3–7 mm long, lobes not recurved or strongly recurved. Mature fruits 1 per inflorescence, globular, 26–40 mm diameter, yellow or yellowish-green, 2-locular. Mature fruits placenta not apparent. Mature fruits interior dry, pericarp 4–7.5 mm thick, fruit attachment shed readily, leaving shallow circular scar. Pedicels at fruiting stage 18–50 mm long, 1.5–2.2 mm thick at mid-point. Seeds black, 3.9–4.8 mm long.
Distribution and habitat. Northern Territory, Western Australia. Red earths in mulga (Acacia aneura) dominated communities, shrublands in arid zone.
Miscellaneous. Subg. Leptostemonum. Data source: specimens.
Illustrations. • flowers. • fruiting plant. • plant. • fruit. • whole plant.
Cite this publication as: ‘Bean, A.R. 2012 onwards. Solanum species of eastern and northern Australia. Version: 29th June 2013. http://delta-intkey.com’.