Solanum species of eastern and northern Australia

DELTA Home

A. R. Bean

Solanum lacunarium

Habit. Prostrate or sprawling, herbaceous resprouter, 0.2–0.4 m high.

Branchlets. Branchlets grey or brown. Branchlet prickles 5–35 per decimetre, straight, acicular or straight, broad-based, 0.5–5 mm long, 5–9 times longer than wide, glabrous. Branchlet hairs stellate. Branchlet stellae sparse to moderate, 0.25–0.3 mm diameter, stalks 0 mm long. Branchlet stellae lateral rays 8–9, porrect. Branchlet stellae central ray absent. Branchlet Type 2 hairs absent.

Leaves. Leaves elliptical or ovate, deeply lobed throughout. Leaf lobes 3–5 on each side, obtuse, lobing index 5–12. Leaves 2.5–6.5 cm long, 1.3–3.5 cm wide, 1.8–2.2 times longer than broad. Leaf apex obtuse, base cuneate or obtuse. Leaf oblique part 0–2 mm long, obliqueness index 0–4 percent. Petioles 0.9–3.2 cm long, 35–55% length of lamina, winged, prickles present.

Upper leaf surface. Upper leaf surface green. Upper leaf surface prickles present on midvein and lateral veins, 35–50, straight, broad-based, 1–4 mm long. Upper leaf surface stellate hairs distributed throughout, protostellae absent, hair density very sparse. Upper leaf surface stellae 0.4–1.3 mm apart, 0.2–0.3 mm across, stalks 0 mm long. Upper leaf surface stellae lateral rays 7–10, porrect. Upper leaf surface stellae central ray 0–0.5 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 white, grey. Lower leaf surface prickles present on midvein only or present on midvein and lateral veins, 6–20, straight, broad-based. Lower leaf surface stellate hair density very dense. Lower leaf surface stellae 0.05–0.1 mm apart, 0.3–0.4 mm diameter, stalks 0 mm long. Lower leaf surface stellae lateral rays 8–9, porrect. Lower leaf surface stellae central ray 0–0.4 times as long as laterals, not gland-tipped. Lower leaf surface simple hairs absent. Lower leaf surface Type 2 hairs absent.

Inflorescence. Inflorescence supra-axillary, cymose (pseudo-racemose). Inflorescence common peduncle 26–46 mm long. Inflorescence rachis prickles present. Inflorescence 5–7-flowered, with some bisexual and some male flowers. Flowers 5-merous. Pedicels at anthesis 7–18 mm long, same thickness throughout, 0.4–0.8 mm thick at mid-point, prickles absent or present. Calyx tube at anthesis 1.5–2.5 mm long. Calyx lobes at anthesis deltate, 1–2 mm long. Calyx prickles at anthesis present, 15–25 per flower, 0.5–3 mm long. Calyx stellae moderate to dense, white, 0.2–0.3 mm across, stalks 0 mm long, lateral rays 7–8. Calyx stellae central ray 0–0.4 times as long as laterals, not gland-tipped. Calyx simple hairs absent, Type 2 hairs absent. Corolla mauve or purple, 8–10 mm long, rotate, inner surface glabrous. Anthers 3.5–4.5 mm long. Ovary with stellate hairs only. Functional style 5–7.5 mm long, protruding between anthers, with stellate and Type 2 hairs. Functional style stellae 0.25–0.35 mm across, lateral rays 4–8, central ray 0–0.4 times as long as laterals.

Fruits. Fruiting calyx lobes less than half length of mature fruit, prickles 1–3 mm long. Mature fruits 1–3 per inflorescence, globular or ellipsoidal or ovoid, 12–15 mm diameter. Pedicels at fruiting stage 14–21 mm long, 0.9–1.1 mm thick at mid-point.

Distribution and habitat. Queensland, New South Wales, Victoria. Qld: Maranoa. NSW: North Western Plains, North Far Western Plains, South Far Western Plains. Grassland or open woodland on cracking clays.

Miscellaneous. Subg. Leptostemonum. Common name: Lagoon Nightshade. Data source: specimens.


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

Contents