Solanum rixosum A.R.Bean, Austrobaileya 6: 759 (2004)
T: Qld, 0.5 km along Duck Creek road, near O'Reilly's Guest House, 11 Dec 1999, A.R.Bean 15899; holo: BRI; iso: AD, CANB, NSW. An image of the type specimen can be found at http://delta-intkey.com/solanum/images/Sol_rixos.jpg
S. furfuraceum auct. non R.Br.: Symon, J.
Solanum sp. B (aff. sporadotrichum) sensu S.W.L.Jacobs & J.Pickard, Pl.
Solanum sp. 1 in Ross, Fl.
Solanum sp. (Benarkin R.J.Henderson H297) in Henderson, Names Distrib.
Erect, rhizomatous perennial shrub, 1-2 m high. Juvenile branchlets with 10-30 prickles per dm; leaves (in outline) broadly ovate, shallowly-lobed, with 1-3 pairs of lobes; lamina 9-15 cm long, 4-8 cm wide, with 10-40 prickles on upper surface. Adult branchlets yellow or rusty; prickles absent or present, 0-15 per dm, straight, acicular, 3-10 mm long, 10-14 times longer than wide; stellae very dense, 0.3-0.4 mm diameter, stalks 0-0.2 mm long; lateral rays 4-8, porrect; central ray 1-2 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent.
Adult leaves ovate, entire or shallowly lobed throughout; lobes 1-3 on each side, obtuse, lobing index 1-1.3; lamina 6-12 cm long, 2.9-4.8 cm wide, 1.8-2.6 times longer than broad, apex acute, base cuneate or obtuse, oblique part 0-4 mm long, obliqueness index 0-4 percent; petioles 0.7-1.4 cm long, 8-14% length of lamina, prickles absent. Upper leaf surface green; prickles 0-10, straight, acicular, 4-10 mm long, prickles absent or present on mid-vein only or present on mid-vein and lateral veins; stellate hairs distributed throughout; proto-stellae absent; ordinary stellae very sparse to sparse, 0.7-1.6 mm apart, 0.4-0.8 mm across, stalks 0-0.2 mm long; lateral rays 6-9, porrect or ascending; central ray 1-1.5 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent. Lower leaf surface yellowish; prickles absent; stellae dense, 0.1-0.4 mm apart, 0.5-0.8 mm diameter, stalks 0.2-0.6 mm long; lateral rays 7-9, porrect; central ray 1-1.5 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent.
Inflorescence supra-axillary, pseudo-racemose, common peduncle 1-6 mm long, rachis prickles absent; 2-15- flowered, weakly andromonoecious, flowers 5-merous; pedicels 6-11 mm long at anthesis, same thickness throughout, 0.5-0.8 mm thick at mid-point, prickles absent. Calyx tube 1.5-3 mm long, lobes attenuate, 7-9 mm long; prickles absent at anthesis; stellae very dense, yellow or brown or rusty, 0.5-0.6 mm across, stalks 0-0.2 mm long, lateral rays 8-9, central ray 1-1.5 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent. Corolla purple, 9-14 mm long, shallowly lobed, inner surface sparsely stellate-hairy; anthers 5-6 mm long; ovary with stellate and Type 2 hairs; functional style 7.5-10 mm long, erect, glabrous or with Type 2 hairs only or with stellate and Type 2 hairs, stellae 0.4-0.5 mm across, lateral rays 6-9, central ray 1-1.5 times as long as laterals.
Fruiting calyx with lobes less than half length of mature fruit, prickles absent. Mature fruits 1-3 per inflorescence, globular, 19-24 mm diameter, yellowish-green or green, 2 or 3-locular; placenta in cross-section stalked, anvil-shaped; mesocarp moist but not juicy; exocarp 0.9-1.2 mm thick; pedicels 17-26 mm long in fruit, 1-1.4 mm thick at mid-point; seeds pale yellow, 2.2-2.7 mm long.
Description by Bean, reproduced, with permission, from Austrobaileya 6: 759 (2004).
Another detailed description by Bean can be found at http://delta-intkey.com/solanum/www/rixosum.htm
Distribution and ecology
Occurs in or adjacent to disturbed areas of rainforest in an area stretching from the Bunya Mts of SE Qld to Kyogle in NE NSW.
Part of the S. macoorai group of subgen. Leptostemonum according to Bean (2004).
Closely related to S. furfuraceum and treated as this species in Symon (1981) and Purdie et al. (1982). The two species differ by
- non-corky thin bark in comparison to thick furrowed corky bark of S. furfuraceum
- sparse stellate hairs on the upper leaf surface, these somewhat denser in S. furfuraceum
- fruiting pedicels longer, 17-26 mm, compared with 4-8 mm in S. furfuraceum
- calyx lacking glandular hairs, these present in S. furfuraceum
- ovary with mixed stellate and glandular hairs, glabrous in S. furfuraceum
- thinner exocarp or "skin", c. 1 mm thick, compared with the 2-2.5 mm thick skin in S. furfuraceum
Derivation of epithet
From the Latin rixosus meaning quarrelsome, a reference to the differences of opinion of botanists regarding the taxonomic status of this species.
QLD: BURNETT DISTRICT: Bunya Mtns, Oct 1919, White s.n. (BRI);
From the web
Images of S. rixosum can be accessed through Bean's description of this species at http://delta-intkey.com/solanum/www/rixosum.htm
Further information on this species in NSW can be seen on the PlantNET site
A photograph of this species by Hugh & Nan Nicholson can be seen on the Terania Rainforest Publishing Photo Library site.
Further information, images and links for this species can be found on the Solanaceae Source site.