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lesser purple fringe bog-orchid, lesser purple fringe orchid, small purple-fringe orchid

large round-leaf orchid, large round-leaf rein orchid, lesser roundleaf orchid, round-leaf bog-orchid, round-leaf orchid

Habit Plants 14–101 cm. Plants 17–62 cm.
Leaves

2–5, wide-spreading, recurved to somewhat ascending, scattered along stem, gradually reduced to bracts distally;

blade lanceolate, oblong-elliptic, or oblong-obovate, 5–22 × 1.5–7 cm.

2, in subequal basal pair lying on ground;

bracts (very rarely, 0–)1–6, scattered along stem;

blade broadly elliptic to orbiculate or oblate, 5–21 × 3–22 cm.

Spikes

lax to very dense.

lax to dense.

Flowers

resupinate, showy, lavender- to rose-purple, rarely white;

lateral sepals reflexed to somewhat spreading;

petals spatulate to broadly obovate or cuneate-oblong, margins dentate-lacerate to sparsely fringed;

lip descending to somewhat porrect, deeply 3-lobed, without basal thickening, 5–13 × 5–17 mm, distal margins of lobes fringed, sometimes deeply, lateral lobes often reflexed or slightly elevated above middle lobe, broadly to narrowly cuneate, middle lobe sometimes reflexed, broadly cuneate-flabellate, often emarginate to 2-fid;

spur slenderly cylindric to slightly clavate, 12–22 mm;

rostellum lobes nearly parallel, directed downward, short, rounded;

pollinaria nearly straight;

pollinia remaining enclosed within anther sacs;

viscidia suborbiculate to broadly elliptic;

ovary slender to stout, 9–16 mm.

resupinate, rather showy;

calyx mostly greenish white;

corolla mostly white;

lateral sepals reflexed to somewhat spreading;

petals lanceolate-falcate, margins entire;

lip descending to somewhat reflexed, linear-oblong to linear-lanceolate, without basal thickening, 7–17 × 1–2.5 mm, margins entire;

spur slenderly clavate, 14–27 mm;

rostellum lobes directed strongly forward, wide-spreading, angular;

pollinaria nearly straight, 3–4.5(–4.8, very rarely) mm;

pollinia remaining enclosed in anther sacs;

viscidia orbiculate;

ovary slender to rather stout, mostly 10–26 mm.

2n

= 42.

= 42.

Platanthera psycodes

Platanthera orbiculata

Phenology Flowering Jun–Aug(–Sep). Flowering Jun–Aug(–Sep).
Habitat Alluvial and swamp forests, stream banks, riparian meadows, moist and seeping slopes, marshes, roadside banks, ditches, old fields Mesic to wet coniferous and deciduous forest, fen forest
Elevation 0–2000 m (0–6600 ft) 0–1500 m (0–4900 ft)
Distribution
from FNA
CT; GA; IA; IL; IN; KY; MA; ME; MI; MN; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; MB; NB; NF; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; ID; IL; IN; MA; MD; ME; MI; MN; MT; NC; NH; NJ; NY; OH; OR; PA; SD; TN; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK
[WildflowerSearch map]
[BONAP county map]
Discussion

Platanthera psycodes is known to hybridize with P. lacera in the northeasternmost portion of its range, where the species bloom simultaneously. Such hybrids are known as P. ×andrewsii (M. White) Luer; see the discussion under P. lacera. A few specimens also suggest very rare hybridization with P. grandiflora.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

The key will permit determination of most specimens of Platanthera orbiculata and P. macrophylla. More precise discrimination of ambiguous specimens is possible by use of the formula from A. H. Reddoch and J. M. Reddoch (1993): spur length + (2 × pollinarium length), which for P. orbiculata is less than 38 and for P. macrophylla is equal to or greater than 38.

Considerable variation in size and shape of leaves occurs, and although to some extent regional in nature, intergradation is complete; recognition of infraspecific taxa is unwarranted. A few collections from isolated areas on the Pacific Coast of Canada are noteworthy, however. Those are small, few-flowered plants with rather narrow leaves borne alternately or suboppositely toward the base of the stem, as in some Asiatic species. They are in some respects very similar to Platanthera freynii Kränzlin, an Asiatic species distinguished primarily by its abruptly narrowed petals, in contrast to the generally broader, but variable, petals in North American plants. These western plants warrant further study to establish their identity and to elucidate relationships between North American and Asiatic species.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 26, p. 565. FNA vol. 26, p. 555.
Parent taxa Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Platanthera Orchidaceae > subfam. Orchidoideae > tribe Orchideae > subtribe Orchidinae > Platanthera
Sibling taxa
P. aquilonis, P. blephariglottis, P. brevifolia, P. chapmanii, P. chorisiana, P. ciliaris, P. clavellata, P. convallariifolia, P. cristata, P. dilatata, P. flava, P. grandiflora, P. hookeri, P. huronensis, P. hyperborea, P. integra, P. integrilabia, P. lacera, P. leucophaea, P. limosa, P. macrophylla, P. nivea, P. obtusata, P. orbiculata, P. peramoena, P. praeclara, P. purpurascens, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
P. aquilonis, P. blephariglottis, P. brevifolia, P. chapmanii, P. chorisiana, P. ciliaris, P. clavellata, P. convallariifolia, P. cristata, P. dilatata, P. flava, P. grandiflora, P. hookeri, P. huronensis, P. hyperborea, P. integra, P. integrilabia, P. lacera, P. leucophaea, P. limosa, P. macrophylla, P. nivea, P. obtusata, P. peramoena, P. praeclara, P. psycodes, P. purpurascens, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
Synonyms Orchis psycodes, Habenaria psycodes Orchis orbiculata, Habenaria orbiculata, Habenaria orbiculata var. lehorsii, Habenaria orbiculata var. menziesii, P. orbiculata var. lehorsii
Name authority (Linnaeus) Lindley: Gen. Sp. Orchid. Pl., 294. (1835) (Pursh) Lindley: Gen. Sp. Orchid. Pl., 286. (1835)
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