Solanum species of eastern and northern Australia


A. R. Bean

Solanum yirrkalense

Habit. Erect, rhizomatous perennial shrub, 0.5–1.5 m high.

Branchlets. Branchlets brown. Branchlet prickles 3–10 per decimetre, straight, acicular, 1–5 mm long, 10–15 times longer than wide, glabrous. Branchlet hairs stellate. Branchlet stellae sparse to moderate to dense, 0.2–0.3 mm diameter, stalks 0–0.1 mm long. Branchlet stellae lateral rays 8–13, porrect or multiradiate. Branchlet stellae central ray absent or present, 0–1 times as long as laterals, not gland-tipped, thready.

Leaves. Leaves elliptical or ovate, entire or shallowly lobed throughout. Leaf lobes 0 on each side or 3–5 on each side, acute or obtuse, lobing index 1–1.4. Leaves 7.5–13 cm long, 3.5–6 cm wide, 2–3 times longer than broad. Leaf apex acute or acuminate, base cuneate. Leaf oblique part 0–3 mm long, obliqueness index 0–2 percent. Petioles 0.5–2.2 cm long, 5–17% length of lamina, prickles absent.

Upper leaf surface. Upper leaf surface green. Upper leaf surface prickles absent or present on midvein only or present on midvein and lateral veins, 0–7, straight, acicular, 3–5 mm long. Upper leaf surface stellate hairs absent or confined to midrib, hair density absent from surface. Upper leaf surface simple hairs absent. Upper leaf surface Type 2 hairs absent.

Lower leaf surface. Lower leaf surface greenish-white. Lower leaf surface prickles absent. Lower leaf surface stellate hair density dense. Lower leaf surface stellae 0.1–0.3 mm apart, 0.3–0.5 mm diameter, stalks 0 mm long. Lower leaf surface stellae lateral rays 7–8, porrect. Lower leaf surface stellae central ray 0.1–0.5 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, cymose (pseudo-racemose). Inflorescence common peduncle 3–12 mm long. Inflorescence rachis prickles absent. Inflorescence 5–35-flowered, with some bisexual and some male flowers. Flowers 5-merous. Pedicels at anthesis 6–10 mm long, same thickness throughout, 0.3–0.4 mm thick at mid-point, prickles absent. Calyx tube at anthesis 1.5–2.5 mm long. Calyx lobes at anthesis deltate or attenuate, 1–3 mm long. Calyx prickles at anthesis absent. Calyx stellae moderate to dense, transparent, 0.2–0.3 mm across, stalks 0 mm long, lateral rays 5–8. Calyx stellae central ray 1–1.5 times as long as laterals, not gland-tipped. Calyx simple hairs absent, Type 2 hairs absent. Corolla white or mauve, 6–8 mm long, deeply lobed, inner surface glabrous. Anthers 3.5–5 mm long. Ovary glabrous. Functional style 4.5–5 mm long, protruding between anthers, glabrous or with stellate hairs only. Functional style stellae 0.2–0.25 mm across, lateral rays 8–9, central ray 0.7–1.5 times as long as laterals.

Fruits. Fruiting calyx lobes less than half length of mature fruit, prickles absent. Mature fruits 1–2 per inflorescence, globular, 15 mm diameter, red, 1-locular (septum absent or incomplete). Mature fruits placenta not apparent. Mature fruits interior juicy, succulent, pericarp 0.7 mm thick. Pedicels at fruiting stage 17–24 mm long, 0.6–0.8 mm thick at mid-point. Seeds pale yellow, 3.5–3.9 mm long.

Distribution and habitat. Queensland. Qld: Cook. Semi-deciduous vine forest on sand, laterite or granite.

Miscellaneous. Subg. Leptostemonum. Data source: specimens.

Cite this publication as: ‘Bean, A.R. 2012 onwards. Solanum species of eastern and northern Australia. Version: 29th June 2013.’.