Synonymy

Solanum dunalianum Gaudich., in Freycinet, Voy. Uranie 448 (1830); t. 58 (1828)

T:Pisang Island, Moluccas, Dec. 1818; P n.v.

Bean (2004) noted that there are two sheets of S. dunalianum at P that were collected by Charles Gaudichaud-Beaupré; he chose the sheet with 5 leaves and the prickly stem and with the label saying “Solanum dunalianum, Aquartia Dl, Ile Pisang, C.G.” as lectotype. [This is not the specimen labelled as the type which can presently (March 2009) be viewed through the Sonnerat database].

Bean further noted that he was uncertain about the correct application of the name S. dunalianum, indicating that the Australian species might be referable to S. torricellense Bitter.

Description

Shrub or small tree to several metres, deep green; young shoots and inflorescence pubescent with minute stellate hairs, the mature twigs and leaves glabrous except leaf axils; prickles absent or 1–2 mm long.

Upper leaves usually in unequal-sized pairs; larger leaf elliptic, the lamina up to 30 cm long and 15 cm wide, concolorous, entire; petiole 20–35 mm long; smaller leaf similar, the lamina up to 15 cm long and 5 cm wide; petiole 5–10 mm long.

Inflorescence often forked, 10–20–flowered; peduncle to first fork c. 10 mm long; rachis 5–10 mm long; pedicels 5–8 mm long, elongated in fruit. Calyx 2–3 mm long; lobes triangular, short. Corolla stellate, deeply incised, 20–30 mm diam., 4–5–lobed, violet. Anthers 4–5 mm long.

Berry globular, 8–10 mm diam., orange or orange-red; fruiting pedicels 1–1.5 cm long. Seeds 3 mm long, colour not known.

Distribution and ecology

In Australia known only from two collections from the far north of Cape York Peninsula and Thursday Island, Qld. Extends from Malesia through P.N.G. to western Pacific islands.

Relationships

Symon (1981) included this species within Sect. Irenosolanum Seithe together with S. tetrandum and S. viridifolium. All are found in the Pacific islands, PNG and northern Australia. All are shrubs or small trees, usually unarmed, have large entire leaves, are glabrous or with only sparse stellate hairs, tapering anthers and red berries.

Whalen (1984) and Bean (2004) both included the same three species within the Dunalianum group of subg. Leptostemonum; none of these species was included in the molecular analysis of the relationships of the species of subg. Leptostemonum conducted by Levin et al.(2006). The group is presently the subject of study for a project at the New York Botanic Gardens

Notes

In 1979 described as the source of a new alkaloid, soladunalinidine.

Reference: GJ Bird, DJ Collins, FW Eastwood & JM Swan (1979). Soladunalinidine, a new dibasic analogue of tomatidine extracted from Solanum dunalianum. Aust. J. Chem. 32: 611.

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Selected specimens

Qld: Embley River, J.M. Swan 141 (AD, BRI, CANB).

Plant status, if any

Solanum dunalianum is listed as vulnerable under the Commonwealth Government’s Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). It is also listed as vulnerable under Queensland’s Nature Conservation Act 1992.

A conservation advice sheet for S. dunalianum can be found at www.environment.gov.au/biodiversity/threatened/species/pubs/13819-conservation-advice.pdf

From the web

An image of a herbarium specimen of S. dunalianum can be found on the Bean interactive key site at http://delta-intkey.com/solanum/images/soldunali001.JPG

One of the type specimens can presently (March 2009) be viewed through the Sonnerat database.

Further links to herbarium collection of this species can be found on the Solanaceae Source site.