Synonymy
Solanum angustum Domin, Biblioth. Bot. 80: 588-9 (1929)
T: Nord-Queensland: steinige und grasige Hügel am Walsh River nördlich von Chillagoe, Feb 1910, K. Domin s.n.; holo: PR.
Solanum parvifolium auct. non R.Br.: Symon, J. Adelaide Bot. Gard. 4: 132 (1981), p.p.
Description
Sprawling, herbaceous resprouter, c. 0.3 m high. Juvenile stage absent. Adult branchlets grey or yellow; prickles 5-30 per decimeter straight, acicular, 3-6 mm long, 10-15 times longer than wide; stellae very dense, 0.3-0.5 mm diameter, stalks 0-0.1 mm long; lateral rays 6-8, porrect; central ray present, 0.5-1 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent.
Adult leaves narrow lanceolate to ovate or elliptical, entire or shallowly lobed throughout; lobes 2 or 3 on each side, obtuse, lobing index 1-1.3; lamina 1.5-4 cm long, 0.4-1.4 cm wide, 3-7.5 times longer than broad, apex obtuse, base cuneate, oblique part 0-1 mm long, obliqueness index 0-3 percent; petioles 0.3-2.2 cm long, 17-55% length of lamina, prickles absent. Upper leaf surface green; prickles 0-3, straight, acicular, 3-6 mm long, prickles absent or present on mid-vein only; stellate hairs distributed throughout; proto-stellae absent; ordinary stellae sparse to moderate density, 0.3-0.9 mm apart, 0.25-0.4 mm across, sessile; lateral rays 6-8, porrect; central ray 0.5-1 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent. Lower leaf surface green or yellowish; prickles absent; stellae sparse to dense, 0.1-0.7 mm apart, 0.3-0.6 mm diameter, stalks 0-0.1 mm long; lateral rays 7 or 8, porrect; central ray 0.5-1 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent.
Inflorescence leaf-opposed, solitary or pseudo-racemose, common peduncle 0-15 mm long, rachis prickles present; 1-4-flowered, flowers 5-merous; pedicels c. 7 mm long at anthesis, same thickness throughout, c. 0.8 mm thick at mid-point, prickles present. Calyx tube 2.5-3 mm long, lobes deltate, 2-2.5 mm long; prickles present at anthesis, 2-10 per flower, 1-4 mm long; stellae dense, transparent, 0.3-0.4 mm across, sessile, lateral rays 7 or 8, central ray 0.5-1 times as long as laterals, not gland-tipped; finger hairs absent; Type 2 hairs absent. Corolla c. 10 mm long.
Fruiting calyx with lobes more than half length of mature fruit, prickles 1-4 mm long. Mature fruits 1 per inflorescence, globular, 16-20 mm diameter, green; pedicels 15-20 mm long in fruit, 0.9-1.2 mm thick at mid-point; seeds pale yellow, 2.5-3 mm long.
Reproduced, with permission, from Bean (2004).
Another detailed description of this species can be found in Bean's interactive key to the eastern Australian species of Solanum at http://delta-intkey.com/solanum/www/angustum.htm
Distribution and ecology
Known only from old collections from the Chillagoe, Stannary Hills and Almaden regions of Cape York Peninsula with one more recent collection (1992) from the Newcastle Range.
Relationships
Considered by Bean (2004) to be a member of the S. ellipticum group of subgen. Leptostemonum.
Notes
Bean (2004) noted that this species is poorly known. It has only been collected four times between 1908 and 1992 and attempts to relocate the specimen from the 1992 site have not been successful.
His placement of it in the S. ellipticum group was provisional.
Selected specimens
QLD: COOK DISTRICT: Stannary Hills, 1908, Bancroft 173 (BRI); Alma-den, Nov 1939, Thurston 575 (QRS); 26 km W of Einasleigh on road to Forsayth, on top of Newcastle Range, Apr 1992, Halford Q958 (AD, BRI, MEL).
As cited in Bean (2004).
From the web
Images of this species can be accessed through the description in Bean's interactive key to the eastern Australian species of Solanum at http://delta-intkey.com/solanum/www/angustum.htm
Further information and links for this species can be found on the Solanaceae Source site.