Jewel Orchids
Robust terrestrials with succulent, above-ground, creeping rhizomes with an erect apex, anchored by wiry roots that appear woolly. The relatively large, broad, asymmetric leaves, which arise in a basal to central rosette, are thin-textured, petiolate and light green or reddish. Spikes terminal on a shoot, hairy. Flowers crowded, right-way-up, dull-coloured, hairy. Dorsal sepal and petals overlapping to form a hood. Lateral sepals divergent. Labellum attached to the anterior base of the column, resembling a pitcher, the surface with numerous multicellular hairs.
Similar Genera
Significant Generic Characters
Terrestrial orchids, evergreen; rhizomes succulent, above-ground, creeping with an erect apex, anchored by wiry nodal roots that appear woolly; leaves petiolate, in a basal to central rosette, glabrous, relatively broad, thin-textured, shiny, light green or reddish; inflorescence spicate, terminal on a shoot; flowers resupinate, relatively large, crowded, dull-coloured (brownish reddish, yellowish), pubescent; dorsal sepal and petals overlapping to form a galea; lateral sepals divergent. Labellum attached to the anterior base of the column, obscurely lobed, deeply pouched but without a spur; hypochile much larger than the epichile, the base deeply pouched, ornamented with numerous, linear multicellular trichomes; epichile caudate, entire, recurved. Column elongate, narrow. Stigma apical, concave, unlobed.
Size and Distribution
A genus of about 20 species distributed in tropical regions from northern India and Japan south to Malaysia and east to New Guinea, Solomon Islands, New Caledonia, Polynesia and Australia. A single endemic species, Salacistis ochroleuca, is restricted to the vicinity of the Atherton Tableland in northeastern Queensland (about 17°15’ S). State occurrence: Queensland.
Ecology
Salacistis ochroleuca grows in friable soil on slopes in highland rainforest in situations of continual high humidity. Elevation ranges from about 600 m to 800 m alt. The climate has a summer wet season (December to March) with the remaining months being much drier with sporadic or intermittent rain.
Biology
Pollination: The flowers of Salacistis ochroleuca are self-pollinating.
Reproduction: Salacistis ochroleuca reproduces solely from seed. Seed dispersal takes 3-4 months from pollination and the capsules develop in an erect position. There is no elongation of the peduncle or pedicels. Apomixis is unknown in the genus.
Seasonal Growth: Salacistis ochroleuca survives the dry parts of the year as quiescent leafy plants.
Flowering: Salacistis ochroleuca flowers between September and October.
Hybrids: Salacistis ochroleuca does not participate in natural hybridisation.
Fire: Salacistis ochroleuca does not grow in fire-prone habitats.
Derivation
Salacistis is named from Mt Salak in Java, the type locality of Salacistis novembrilis.
Botanical Description
Perennial, evergreen, terrestrial herbs, sympodial. Roots wiry, produced from rhizome nodes, appearing woolly from a covering of root hairs. Rhizome cylindrical, fleshy, unbranched or sparsely branched, prostrate. Stem erect, usually 1 shoot per plant, similar to the rhizome. Pseudobulbs absent. Trichomes present on peduncle, rhachis, bracts, ovaries and exterior of perianth, short, unbranched, multiseriate, eglandular. Leaves lasting 1-2 seasons, few per shoot, spirally arranged, asymmetrical, glabrous, petiolate, sheathing at the base, forming a loose rosette. Leaf lamina longer than wide, asymmetric, thin, membranaceous, flat, smooth, entire, light-coloured, sometimes reddish. Venation acrodromus to campylodromus, with cross-veinlets and few anastomoses. Inflorescence spicate, terminal on a growth, few-several-flowered, erect. Peduncle longer than the rhachis, pubescent, with semi-sheathing to projecting, glabrous or pubescent sterile bracts. Floral bracts sheathing, glabrous or pubescent. Ovary elongate, projecting at an angle from the rhachis, straight, twisted, pubescent. Flowers resupinate, crowded, sometimes not opening widely, dull coloured (pink, brownish or yellowish), externally pubescent, sessile to subsessile. Dorsal sepal closely overlapping the petals to form an upright galea. Lateral sepals free, divergent, occasionally porrect. Petals of similar length to the sepals, forming a galea with the dorsal sepal, strongly asymmetric, membranous, margins irregular, erose or lacerate. Labellum fixed by its basal margins to the anterior margins of the column base, immoveable, pitcher-shaped, markedly dissimilar in size and shape to the sepals and petals, ecalcarate. Labellum lamina obscurely divided into a hypochile and an epichile; hypochile much larger than the epichile, entire, with a broad deeply pouched base, ornamented proximally with numerous, irregularly arranged, multicellular trichomes; epichile sessile, caudate, usually recurved or coiled; apex entire. Callus consisting of a single low flat keel that extends the length of the hypochile. Nectar absent. Column lacking free filament and style, narrow, elongated. Column wings narrow. Column foot absent. Pseudospur absent. Anther dorsal, 2-celled, erect, persistent, basifixed, with an extended rostrum. Pollinarium present. Pollinia 2, clavate, deeply grooved, straight, yellow, sectile, attenuated into stalks that attach to the viscidium (when present). Viscidium present (sometimes absent). Rostellum ventral, elongate, narrow. Stigma apical, unlobed, concave. Capsules dehiscent, pubescent, erect, often with persistent floral parts; peduncle not elongated in fruit; pedicels not elongated in fruit. Seeds numerous, light coloured, winged.
Taxonomy
Within the subtribe Goodyerinae Salacistis is distinguished by the hairy resupinate flowers, simple pitcher-like labellum with a deeply saccate base but without a spur, ventral surface ornamented with subulate multicellular hairs, narrow elongate column, pollinia attenuated into basal stalks and stigma apical and unlobed.
Salacistis is included within Goodyera in most modern floras but molecular studies show conclusively that both genera are distinct and Salacistis should be reinstated.
Notes
The Australian species was identified as Salacistis ochroleuca (see Jones and Clements 2004).
Nomenclature
Salacistis Rchb. f., Xen. Orch., 1: 214 (1856). Type species: Salacistis novembrilis Rchb. f.
Infrageneric Taxa: No infrageneric taxa are recognised.
References
Dockrill, A.W. (1969). Australian Indigenous Orchids. Volume 1. The Society for Growing Australian Plants, Halstead Press, Sydney.
Dockrill, A.W. (1992). Australian Indigenous Orchids. Volume 1 & 2. Surrey Beatty & Sons in association with The Society for Growing Australian Plants, Chipping Norton, NSW.
Jones, D.L. and Clements, M.A. (2004). Miscellaneous new species, new genera, reinstated genera and new combinations in Australian Orchidaceae. Orchadian 14(8): Scientific Supplementi-xvi.
Pridgeon, A.M., Cribb, P.J., Chase, M.W. and Rasmussen, F.N. (eds), (2003). Genera Orchidacearum, Vol. 3. Oxford University Press.