The Cattleyas and Their Relatives: The Debatable Epidendrums - Tapa dura

Anacheilium (Epidendrum subgenus Osmophytum of Lindley) is a group of species most notable for the lip being non-resupinate; the usually unlobed lip turned upwards often in the form of a shell or feather, generally the most attractive portion of the flower. Other orchids in various genera have this trait, but in this large group all the species share the trait. Resupination occurs in most orchid flowers, that is, the flower is actually lip uppermost during development, and as the bud matures, it rotates on the pedicel to present the lip down. We have all seen the occasional flower that did not turn over correctly, due to environmental conditions. These Anacheilium species keep their flowers non-resupinate under all conditions.

Another trait the Anacheilium species share is that the inflorescence has a spathe, or covering, that protects the emerging inflorescence. The spathes are either green or green becoming brown, and are sometimes quite large, sometimes rather insignificant. Encyclia species do not have this spathe, though Cattleya species do, as do many other Epidendrum species. The lips of these species often have a cushionlike callus covered with fine hairs like peach fuzz. The species have a three-winged or three-sided fruit (never oval or round). The column rostellum is undivided, and the column has three knobs at the apex (distally), called teeth in the literature. These teeth are equal in length, size, and shape, with a few exceptions; a feature that separates them from other genera in the Prosthechea (sense of Higgins) group. Mostly likely, different pollinators determine the need for same versus different shaped teeth. Most Anacheilium species are apparently wasp- or bee-pollinated, and many have names based on this relationship (van der Pijl and Dodson 1966).

Another essential characteristic, though not obvious unless the flower or plant is preserved in alcohol, is the presence of unusually numerous fans of raphide (needle-shaped) crystals, especially in the flowers. These crystals are apparently glycosidic in composition, but not identical to the oxalate crystal bundles found in many other types of plants, though they may serve the same function. They may be dissolved in hydroxide solutions. They became apparent when plant and flower parts are preserved in alcohol for study, and the resulting dehydration of the tissues made them especially noticeable (see Pabst and Pinto 1981). The raphides, no doubt, provide a deterrent from slugs or other animals, as the needles of the crystals can be painful when penetrating the tongue or linings of the mouth, throat, and digestive tract.

Some researchers consider Anacheilium a part of Encyclia and others consider it part of Hormidium. The key characters of Lindley's subgenus Anacheilium must be reviewed more strictly in any scheme for subdividing Epidendrum. In preparing this section, we did consider the treatment by Brieger et al. (1977), who subdivided the genus Osmophytum into three sections: Osmophytum, Cochleata, and Glumacea. These names are not validly published as sections by just using them in the book, and are of no utility as they were mentioned without descriptions.

Furthermore, it is debated today whether Osmophytum or Anacheilium should be the correct name for this assemblage, and that requires some research into the history of each name. Epidendrum cochleatum, the earliest named species for this section of the the cockleshell orchids was given a polynomial by Plumier in 1703 and another by Burmann in 1758 when he published Plumier's work. Linnaeus condensed the polynomials to a binomial epithet in 1763, renaming it Epidendrum cochleatum. This species was one of the earliest of New World orchids to be taken to England or Europe for cultivation. Hoffmannsegg in Germany published Anacheilium cochleatum in 1842 based on the species Epidendrum cochleatum, and thus a new segregate genus from Epidendrum was proposed.