Epiphytes or lithophytes with very short almost indiscernible rhizomes anchored by thin roots that arise from the base of the pseudobulbs. Pseudobulbs hard, commonly short and broad, but those in section Blepharoglossum are elongate and taper from a swollen base. Leaves 1-5 per pseudobulb, confined to the apical region, conduplicate, thin-textured but tough, longer than wide, with an entire or unequally notched apex. Racemes slender, emerging with a developing new growth. Flowers lasting several days, relatively small, dull coloured. Sepals and petals narrow, spreading. Labellum stiffly attached to the base of the column, larger than the other segments, in many species sharply recurved near the middle and usually widening towards the apex. Callus consisting of relatively obscure basal ridges or keels that produce nectar. Column relatively long, slender, incurved, obscurely winged.
Significant Generic Characters
Epiphytic/lithophytic orchids; rhizomes almost indiscernible; roots thin, from the base of the pseudobulbs; pseudobulbs hard, multinoded, short and broad or elongate and lageniform (sect. Blepharoglossum); leaves 1-5 per pseudobulb, confined to apical nodes, conduplicate, thin-textured but tough, longer than wide, basally sheathing, apex entire or unequally notched; racemes terminal, emerging with a developing new growth, multiflowered; flowers lasting several days, relatively small, dull coloured, often scented; sepals and petals narrow, spreading; labellum unlobed or 3-lobed, stiffly attached to the column base, larger than the other segments, in many species sharply recurved near the middle, usually widening towards the apex; margins entire or shortly toothed (sect. Blepharoglossum); callus consisting of relatively obscure basal ridges or keels that produce nectar; column relatively long, slender, incurved, obscurely winged.
Size and Distribution
A genus of about 150 species widely distributed in tropical regions with concentrations in Asia and New Guinea. Eight species occur in Australia, 7 endemic. The Australian species are restricted to the eastern side of the continent between the Iron Range (12°36' S) on Cape York Peninsula, Queensland and Mumbulla Mountain near Bega (36°40' S) in south-eastern New South Wales, with a concentration in the Wet Tropics. State occurrence: Queensland, New South Wales.
The native epiphytic species of Cestichis range from low altitudes in the coastal lowlands to more than 1100 m alt. in the ranges and tablelands of northeastern Queensland. Two species in New South Wales and southern Queensland are strict lithophytes, growing on boulders, cliff faces and rocky escarpments. The other native species have less stringent requirements, growing on a range of trees as well as rocks. These orchids mainly grow in sheltered moist situations in rainforest and open forest, occasionally extending their range into drier sites. In the tropics the climate has a dominant summer wet season (December to March) when the vast majority of rain falls, with the remaining months being much drier and having sporadic to intermittent rain. Species growing in subtropical and temperate regions are subject to less extremes. The plants grow actively during the spring and summer months and are relatively quiescent for the remainder of the year.
Pollination: The flowers of native epiphytic species of Cestichis last several days and are insect-pollinated. Although poorly studied, the main vectors appear to be flies and mosquitoes that are attracted to the flowers by unusual scents and feed on nectar produced on the labellum.
Seasonal Growth: Cestichis plants grow actively in summer and autumn and are relatively quiescent for the remainder of the year.
Flowering: Flowering occurs mainly in autumn, winter and spring.
Hybrids: Natural hybrids are unknown in these orchids.
The name Cestichis is a compound derived from a combination of the generic name Stichorchis and caespitosa, the specific epithet of Malaxis caespitosa.
Perennial, evergreen, epiphytic or lithophytic herbs, sympodial. Plants glabrous. Roots filamentous, produced from the base of a newly maturing pseudobulb. Stems reduced or absent. Pseudobulbs present, either short and ovoid to conical (section Cestichis), or elongate and tapered from a swollen base (section Blepharoglossum), fleshy, multiple-noded. Trichomes absent. Leaves lasting several seasons, lateral or apical, 1-several per shoot, sheathing at the base, fixed or articulate (Cestichis coelogynoides), sessile, conduplicate, much longer than wide, smooth. Venation acrodromus. Inflorescence racemose, few to many-flowered, erect or arcuate, terminal, arising with the new growth, the flowers opening before the new growth has matured. Peduncle much shorter than the rhachis, terete or biconvex, with sterile bracts. Floral bracts small, sheathing or free. Pedicels short, thin. Ovary elongate, straight or curved, smooth or ribbed. Flowers resupinate, widely spaced to crowded, dull coloured (green, yellowish green, yellowish orange, red or purplish), often with a greasy appearance, often strongly scented, pedicellate. Dorsal sepal free, of similar size and shape to the lateral sepals, often recurved or reflexed. Lateral sepals free, of similar size and shape to the dorsal sepal, often recurved or reflexed. Petals subsimilar to the sepals, usually narrower, sometimes shorter (Cestichis coelogynoides). Labellum fixed by its base to the anterior column base, immoveable, markedly dissimilar in size to the sepals and petals, ecalcarate. Labellum lamina entire or three-lobed, usually sharply reflexed back on itself just below the middle, sometimes gently flexed (Cestichis coelogynoides), often dilated towards the apex; lateral lobes, if present, obscure; margins entire or serrulate (sect. Blepharoglossum); apex entire, truncate, apiculate, emarginate, erose or papillate. Spur absent. Callus obscure, mostly basal, consisting of plates or low ridges or small paired calli. Nectar usually present. Column lacking free filament and style, elongated, sometimes basally enlarged, incurved distally. Column foot absent. Pseudospur absent. Column wings present but usually vestigial, mainly apical, ventral, narrow or semi-round. Anther terminal, incumbent, 2-celled, persistent, basifixed, smooth or papillate, rostrate. Pollinarium absent. Pollinia 4 in 2 pairs, crescentic or hemispherical, greenish, yellow or orange, hard, waxy. Viscidium absent. Rostellum ventral, transverse, protruding. Stigma entire, transverse, concave. Capsules dehiscent, glabrous, erect; peduncle not elongated in fruit; pedicels not elongated in fruit. Seeds numerous, light coloured, winged.
Cestichis was previously included in Liparis, the connection based mainly on floral similarities. Molecular studies of the Malaxideae show that floral morphology in the tribe is conservative and vegetative characters are of greater significance in the classification of the group (Cameron 2005). The type of Liparis sens. str. is a terrestrial with plicate leaves. By contrast species of Cestichis are epiphytes with conduplicate leaves. See also Diteilis and Empusa.
Cestichis Thouars, Orch. Afr. t. 90 (1822), nom. illeg., fide Rasmussen et Rasmussen (1975).
Liparis L.C.Rich. subgen. Cestichis (Thouars ex Pfitzer) Schltr. sect. Hologlossum Schltr., Repert. Spec. Nov. Regni Veg. Beih. 1: 199, 208 (1 Dec.1911). Type species: Liparis caespitosa (Thouars) Lindl .
2. Cestichis sect. Blepharoglossum (Schltr.) M.A.Clem. and D.L.Jones, Orchadian 15(1): 40 (2005). Pseudobulbs lageniform, elongate, broadest at the base then tapered, labellum margins minutely denticulate-serrulate.
Cameron, K.M. (2005). Leave it to the leaves: a molecular phylogenetic study of Malaxideae (Epidendroideae, Orchidaceae). Am. J. Bot. 92: 1025-1032.
Clements, M.A. (1989). Catalogue of Australian Orchidaceae. Austral. Orch. Res. 1: 160.
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. & Clements, M.A. (2005). Miscellaneous nomenclatural notes and changes in Australian, New Guinea and New Zealand Orchidaceae. Orchadian 15(1): 33-42.