Corallorhiza trifida Chatelain
Early Coral-root.
Orchidaceae, orchid family.
Spec. Inaug. Corallorhiza 8: 1760.
Ophrys corallorhiza L., Sp. Pl. 945. 1753.
Corallorhiza corallorhiza (L.) Karst.
Corallorhiza trifida
var. verna (Nutt.) Fernald
Vegetative morphology. Plants perennial herbs; 10–30 cm high; not caespitose; saprophytes lacking chlorophyll, with single flowering stems, arising from a coral-like rhizome. Roots pallid-brown, or red-brown. Caudex absent. Ground-level or under-ground stems horizontal, or vertical and often branched (the ground-level stem system resembles coral; hence the common name); rhizomatous; elongate; 2–5 mm wide. Scales absent. Aerial stems erect; not conspicuously jointed; circular or oval in cross-section; with 0 ridges; glabrous, or sparsely hairy (with very few hairs); stem hairs spreading (when present). Leaves absent, or reduced and scale-like near the base of the stem; merely achlorophyllous sheathing scales.
Reproductive morphology. Flowering stems present. Flowering stems with leaves (reduced to sheathing scales); glabrous. Flowers in inflorescences (that can be compact or elongate). Inflorescence spicate (sometimes appearing so when flowers are subsessile), or racemose; dense, or diffuse; linear; 1–6 cm long; 1–2 mm wide; not elongating as the fruit matures; main axis glabrous. Pedicels absent, or present; glabrous. Pedicels bract leaves 0.9–1.1 mm long; 0.4–0.7 mm wide. Flowers per inflorescence 4–6(–9); medium-sized, 5–15 mm in diameter or length; zygomorphic. Perianth present. Calyx sepals 3; free (but contiguous with the receptacle covering the inferior ovary, so they may look fused in the lower part); 2.5–4 mm long; 1–1.4 mm wide. Calyx yellow, or brown; herbaceous; without sessile glands; glabrous. Petals free; same length as the calyx; 3; brown (in arctic island specimens found to date), or white; with contrasting markings (bluish or purple spots on lip); elliptic (or narrowly oblong, the two lateral petals), or obovate (the apparently lower petal which is modified into a lip, or insect landing platform); unlobed (the lateral petals), or shallowly lobed (with two short parallel ridges, the lip petal); 2.5–5 mm long; 1–1.5 mm wide; not spurred. Stamens 1, or 2 (modified as pollen packages (pollinia) attached to a floral column that also bears the stigma and is characteristic of the orchid family). Anthers yellow. Gynoecia inferior. Carpels syncarpous; 3. Styles absent (possibly modified as the petaloid floral column). Stigmas modified into a receptive area near the pollinia and the top of the column. Placentation parietal. Ovules hundreds. Fruit stalked. Fruit with calyx persisting; dry; a capsule; ellipsoid; not distinctly flattened; dehiscent; splitting to the base into separate segments. Fruit 8–13 mm long; 4–7 mm wide; yellowish, or brown; glabrous, or hairy (sometimes slightly so); surface venation ribbed. Seeds hundreds, tiny and light; 0.5 mm long (approximately); white, or yellowish; with surfaces reticulate.
Chromosome information. 2n = 40, 42. 38-42. - Hagerup (1941a northern Europe); Sørensen and Westergaard in Löve and Löve (1948 Greenland); Löve (1954b Iceland); Löve and Löve (1956b Iceland, 1981c central Canada); Jørgensen et al. (1958 Greenland); Sorsa (1963c Finland, 2n = c.42); Laane (1967 Norway); Krogulevich (1976 northern Siberia); Averyanov (1979 northwestern Russia 2n = 38); Dalgaard (1988 western Greenland). Several more southern counts.
Distribution. Northern hemisphere distribution: circumpolar, or circumboreal; Greenland, Canada, United States, Eurasia. Range in the Canadian Arctic Archipelago limited. Rare (2 records). Arctic Islands: Baffin. Only found in two locations on Baffin Island, within Auyuittuq National Park Reserve.
Ecology and habitat. Substrates: river terraces, tundra, slopes; moderately well drained areas; sand, moss.
Notes. This orchid contains no chlorophylls, but is a pinkish brown.
It is a saprophyte and gets its nutrients from mycorhizae on the roots. Because
of the complex relationship between the orchid and the environment in which it
is growing, this species is almost impossible to transplant and should be left
growing where it is found.
This species was first reported from Baffin
Island in 1997 by Joyce Gould (Can. Field-Naturalist, 111: 471–472). She
found this species at two sites on 1995, in Auyuittuq National Park Reserve,
Baffin Island, and prepared a plant voucher from one of them. The specimen was
deposited at DAO.
This species is circumboreal (Hultén 1968). Known
from the continental Northwest territories north to the treeline (Porsild 1943),
the Ungava (Cayouette 1984), and western Greenland (Hultén 1968), it was
not an altogether unexpected find on southe eastern Baffin Island (Gould 1997).
Both of the populations found by Gould (1997) were in fluvial deposits. One
population was found on the east side of a river, "at the base of an end moraine
and of a fluvial terrace just south of a small tributary," in a habitat
dominated by Arctic willow (Salix arctica) and moss (Pohlia
drummondii), and with Arctagrostis latifolia, Pyrola
grandiflora, Poa arctica, Persicaria vivipara,
Pedicularis flammea, and Carex species The second
population was found at the base of a colluvial slope, among Salix
arctica, the moss Aulocomnium turgidum, and a lichen
Stereocaulon sp. Hultén (1968, p. 329) describes its habitat as
"wet places, woods, bogs." Scoggan (1978, p. 528) notes the habitat as "bogs,
thickets and woods", while in the Northwest territories Porsild and Cody (1980,
p. 213) describes the habitat as "turfy, open places".
Illustrations. • Plant in habitat. Plant from Auyuittuq Park, Baffin Island, Nunavut. Photo by Joyce Gould, 1995. Plant growing with Salix arctica, moss and lichen (Stereocaulon, a white lichen, just visible in the photo at bottom). • Close-up of plant. Photograph taken in the field by Joyce Gould, July 1995. Note spots on lip (petal, white arrow), and three sepals (hence the name "trifida"), attached at the top of the inferior ovary (black arrow). Plant approximately 8 cm tall. • Close-up of plant. Close-up of plants from herbarium specimen DAO 685952. Plants showing both flowers and developing fruit. • Close-up of inflorescence. Close-up of inflorescence of herbarium specimen Note zygomorphic orchid flowers in a raceme, usually of 6 to 9 flowers. Colour faded, but lip of corolla usually spotted. Specimen: N.W.T. Aklavik, R.T. Porsild 6575, 28 June 1931. CAN 17064. • Close-up of fruit. Close-up of dehisced capsules of early Coral-root. Herbarium specimen West Greenland, Qorqut, A.E. Porsild 8785, July 17–18, 1943. CAN 154045. • Herbarium specimen. Specimen collected in Auyuittuq National Park Reserve, Baffin Island, Nunavut, 65°25'30"N, 65°27'04"W. Joyce Gould, 2 July 1995. DAO 685952. • Distribution map.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
