Solanum hoplopetalum Bitter & Summerh., Bull. Misc. Inform. 116 (1926)
T: Merredin, W.A., May 1925, E.J. Limbourne s.n.; holo: K; iso: MEL.
Sprawling, clonal, perennial herb with usually annual stems to 35 cm long, green; prickles to 14 mm long, abundant on all parts.
Leaves elliptic; lamina 4–12 cm long, 1–5 cm wide, concolorous, deeply lobed, hispid with simple, often glandular hairs, and minute glandular hairs; lobes oblong to triangular, toothed or shallowly lobed; petiole 15–45 mm long.
Inflorescence 4–8–flowered; peduncle to 30 mm long; rachis 10–20 mm long; pedicels 5–13 mm long. Calyx 6–13 mm long, enlarged in fruit; tube almost obscured by prickles; lobes narrowly triangular, 2–5 mm long. Corolla broadly stellate to subrotate, 15–30 mm diam., pale blue or white. Anthers 4–6 mm long.
Berry globular or depressed globular, 15–20 mm diam., bright green, drying almost black; fruiting calyx 15–20 mm diam. Seeds 2.5 mm long, dark grey. n=12.
Distribution and ecology
Occurs in south-western W.A. where sometimes a minor weed of cereal crops and sheep grazing areas. Possibly naturalised in the 90-mile Desert region of south-eastern S.A. but not collected there since the 1940's. The status of the collection, P.G.Wilson 10895, collected from Heywood Island in the Bonaparte Archipelago of northern W.A. in May 1972 is unknown.
Common on sandy plains, in open woodlands, cultivated areas and roadsides.
Prickly Potato Weed, Afghan Thistle.
Closely related to, and previously confused with, S. hystrix R. Br.; distinguished by presence of hispid and reduced stellate hairs (which may be glandular) and minute glandular hairs.
For a more comprehensive account of the distribution and separation of this species and S. hystrix see B. Lepschi, Recognition and distribution of Solanum hoplopetalum and S. hystrix (Solanaceae) in Australia. Nuytsia 10: 467–470 (1996).
Considered by Bean (2004) to be a member of the S. hystrix group of subgen. Leptostemonum.
Martine et al. (2006 & 2009) included S. hoplopetalum in their molecular study of the dioecious species of the Dioicum group and indicated in the second of these papers that S. hoplopetalum was part of a clade composed of andromonoecious species from Africa and Australia.
References: Martine, C.T., D. Vanderpool, G.J. Anderson, and D.H. Les (2006). Phylogenetic relationships of andromonoecious and dioecious Australian species of Solanum subgenus Leptostemonum section Melongena: Inferences from ITS sequence data. Systematic Botany 31: 410-420; Martine, C.T., G.J. Anderson & D.H. Les (2006). Gender-bending aubergines; molecular phylogenetics of cryptically dioecious Solanum in Australia. Australian Systematic Botany 22: 107-120.
The status of S. hoplopetalum as a weed is discussed in W.T. Parsons and E.G. Cuthbertson, Noxious Weeds of Australia, Inkata Press, Melbourne (1992).
W.A.: c. 110 km E of Norseman, K.M. Allen 224 (PERTH); near Broad Arrow, D.E. Symon 9913 (AD, CANB); 30 km W of Coolgardie, Oct. 1961, J.H. Willis (MEL).
From the web
Further information can be found on the FloraBase site.
Limited information and links for this species are available on the Solanaceae Source site.
Information sources about this species as a weed in Australia can be seen at www.hear.org/gcw/species/solanum_hoplopetalum/