Cryptostylis R.Br.
Slipper Orchids

Scientific Description

Family Orchidaceae.

Habit and leaf form. Herbs; evergreen. Leaves well developed (usually), or absent (C. hunteriana only). Autotrophic, or saprophytic (C. hunteriana only). Perennial. Leaves basal. Tuberous (fleshy, clustered, spreading for fairly long distances in the upper layers of soil). Helophytic, or mesophytic. Leaves medium-sized to large; alternate; spiral; leathery; imbricate, or not imbricate; petiolate. Petioles long. Leaves simple. Leaf blades entire; flat; broad; parallel-veined; cross-venulate, or without cross-venules. Leaf blade margins entire. Leaf anatomy. Hairs absent. Stem anatomy. Secondary thickening absent.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous (the male Ichneumon wasp, Lissopimpla semipunctata). Pollination mechanism conspicuously specialized (the flowers are pollinated while the male wasp attempts to mate with the flowers - as no hybrids have been found the flowers apparently have some internal barrier to prevent cross-pollination).

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’. Inflorescence many-flowered (several to numerous flowered). Flowers in racemes (loose). The terminal inflorescence unit racemose. Inflorescences scapiflorous, or not scapiflorous; terminal. Flowers small to medium-sized; odourless; very irregular; zygomorphic; not resupinate (the column situated below, rather than above the column). The floral asymmetry involving the perianth and involving the androecium. Flowers 3 merous; cyclic; supposedly basically pentacyclic. Perigone tube absent. Perianth of ‘tepals’, or with distinct calyx and corolla; 6; 2 -whorled; isomerous (but zygomorphic); free. Calyx (if the outer whorl be so designated) 3, or 5 (by misinterpretation); 1 -whorled; polysepalous. Corolla (i.e. the members of the inner whorl) 3; polypetalous; imbricate. Androecium 3, or 1 (by misinterpretation). Androecial members free of the perianth; united with the gynoecium (fused with the style to form a colum or ‘gynostemium’; column very short and broad, with lateral appendages); coherent (via the gynostemium); 1 - adelphous; theoretically 2 -whorled. Androecium including staminodes, or exclusively of fertile stamens (by misinterpretation). Staminodes 2 (these anterior, supposedly the abaxial pair of the inner whorl). Stamens 1 (this across the flower from the labellum, i.e. anterior, supposedly representing the outer whorl); reduced in number relative to the adjacent perianth; alterniperianthial (i.e. with reference to the single stamen, across the flower from the labellum); filantherous, or with sessile anthers. Anthers dorsal, erect; dorsifixed to basifixed; dehiscing via longitudinal slits; introrse; tetrasporangiate; appendaged, or unappendaged. Pollen shed in aggregates; in the form of pollinia (pollinia 4). Gynoecium 3 carpelled. The pistil 1 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; eu-syncarpous; inferior. Ovary unilocular; 1 locular. The ‘odd’ carpel anterior (away from the labellum). Gynoecium stylate. Styles 1 (inflexed); apical. Stigmas 1; 3 - lobed (but becoming much modified in form, the apex of the median lobe forming the ‘rostellum’); wet type; papillate; Group III type. Placentation parietal. Ovules not differentiated; in the single cavity 30–100 (i.e. very numerous); non-arillate; anatropous.

Fruit and seed features. Fruit non-fleshy; dehiscent; a capsule. Capsules septicidal, or loculicidal. Fruit 30–500 seeded (i.e. seeds usually very numerous). Seeds endospermic (endosperm development arrested very early), or non-endospermic; minute; without starch. Embryo rudimentary at the time of seed release, or weakly differentiated. Seedling. Seedling collar not conspicuous. Primary root ephemeral.

Geography, cytology, number of species. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, South Australia, Queensland, New South Wales, Victoria, and Tasmania. South-West Botanical Province.

Additional characters Perianth of 5 similar members and the median inner member modified into the labellum (labellum large, undivided, the base enclosing the column, usually reddish and ornamented with hairs or glands; other perianth members linear, inconspicuous). Leaves solitary, or not solitary (to several). Leaves erect. Labellum insect-like. Perianth not glossy.