Platanthera convallariifolia

Fischer ex Lindley

Gen. Sp. Orchid. Pl., 287. 1835.

Synonyms: Limnorchis convallariifolius (Fischer ex Lindley) Rydberg
Treatment appears in FNA Volume 26. Treatment on page 559. Mentioned on page 554, 558, 561.

Plants 15–27 cm. Leaves few–several, ascending to rather wide spreading, scattered along stem or commonly loosely clustered on distal portion, gradually reduced to bracts distally; blade elliptic-lanceolate to elliptic-oblong, 4.5–12 × 0.7–2.5 cm. Spikes moderately dense. Flowers resupinate, not showy, sometimes conspicuous, whitish green, perhaps more yellowish on lip; lateral sepals spreading; petals ovate-falcate, margins entire; lip descending, linear to lance-linear, without basal thickening, 4–9 × 1–2 mm, margins entire; spur slenderly to markedly clavate, rarely more slender, 4–8 mm, apex obtuse; rostellum lobes widely divergent, directed downward, slightly angular, very small, obscure; pollinaria straight; pollinia remaining enclosed in anther sacs but apparently often fragmenting; viscidia oblong to oblong-spatulate or elliptic-suborbiculate; ovary slender to stout, mostly 6–10 mm.


Phenology: Flowering late Jun–early Aug.
Habitat: Wet meadows, tundra, marshes, fens, stream banks, shores, seeping slopes
Elevation: 0–400 m

Distribution

V26 1139-distribution-map.jpg

Alaska, Asia (Kamchatka to Hokkaido)

Discussion

Platanthera convallariifolia is commonly reported from the Aleutians and adjacent coastal Alaska based on short, very broad-leaved plants with rather large flowers in dense, thick inflorescences. Those plants, however, apparently represent robust, maritime phenotypes of P. huronensis or in some cases P. stricta or P. dilatata comparable to those seen in Piperia elegans and Spiranthes romanzoffiana. In fact, typical Asiatic Platanthera convallariifolia is a slender-leaved plant entirely comparable in habit to P. huronensis. The two species are very similar, and they share a tetraploid chromosome number. Typical Asiatic P. convallariifolia is characterized by a linear lip and clavate spur about 2/3 to nearly the length of the lip. The lip occasionally varies to slightly lanceolate and the spur to somewhat saccate. The column appears somewhat broader than in P. huronensis, and viscidia also are apparently rather broad. A few specimens from the Aleutians and Alaskan peninsula exhibit these floral characteristics. Vegetatively, however, some Alaskan material is distinctive in the position and orientation of the leaves. In floral and vegetative characters, Alaskan plants furthermore intergrade with P. huronensis. Whether Alaskan plants are truly referable to P. convallariifolia is uncertain, and the status of the Asiatic species also needs study. Both P. convallariifolia and the Alaskan plants here referred to it appear to combine features of P. huronensis and P. stricta. Platanthera convallariifolia may have arisen through hybridization of these two species, or of P. stricta and P. dilatata, thus accounting for the difficulty in identification. The description presented here is based on few Alaskan plants and is apt to be too restrictive; therefore the poor understanding of the plant makes the present delimitation and distinctions from P. huronensis rather arbitrary.

Selected References

None.

Lower Taxa

None.

"wide" is not a number.

self-pollination +
Charles J. Sheviak +
Fischer ex Lindley +
indehiscent +
not +  and articulate +
conduplicate +  and plicate +
4.5 cm45 mm <br />0.045 m <br /> (12 cm120 mm <br />0.12 m <br />) +
elliptic-lanceolate +  and elliptic-oblong +
0.7 cm7 mm <br />0.007 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Alaska +  and Asia (Kamchatka to Hokkaido) +
0–400 m +
3-merous +, sessile +  and pedicellate +
yellowish +  and whitish green +
conspicuous +  and not showy +
ellipsoid;cylindric +
Wet meadows, tundra, marshes, fens, stream banks, shores, seeping slopes +
lateral +  and terminal +
petiolate +, sessile +  and simple +
spreading;ascending +
Few (?) +  and Several (?) +
reduced +
linear +  and lance-linear +
descending +
3-partite +  and lobed +
larger +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
entire +  and fringed +
1mm +  and 2mm +
differing in form and color +
slender +  and stout +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1-many-flowered +  and cymose +
pendent +  and erect +
ovate-falcate +
Flowering late Jun–early Aug. +
Gen. Sp. Orchid. Pl., +
aerial +  and subterranean +
lancefusiform +
slender +
downward +  and directed +
minute +
free +, distinct +, adnate +  and connate +
foliaceous +
not +  and alike +
clavate +
slender +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
leafless +  and leafy +
pendent +  and erect +
proliferous +
thickened +  and stout +
concave +  and convex +
Limnorchis convallariifolius +
Platanthera convallariifolia +
Platanthera +
species +
oblong +  and oblong-spatulate or elliptic-suborbiculate +
aquatic +, lithophytic +, terrestrial +  and epiphytic +
saprophytic +, photosynthetic +  and mycotrophic +
erect to somewhat +