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greater roundleaf orchid, large round-leaf orchid, large-leaf bog-orchid

purple fringeless orchid

Habit Plants 23–63 cm. Plants 35–105 cm.
Leaves

2, in subequal basal pair lying on ground;

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

blade broadly elliptic, orbiculate, or oblate, 7–24 × 5–19 cm.

2–5, spreading to ascending, scattered along stem, gradually reduced to bracts distally;

blade lanceolate, elliptic, oblong-elliptic, or oblance-oblong, 7–27 × 1.2–5 cm.

Spikes

lax.

lax to dense.

Flowers

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, 10–23 × 1–2.5 mm, margins entire;

spur slenderly clavate, 28–46 mm;

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

pollinaria nearly straight, (4.6–)4.7–6.8 mm;

pollinia remaining enclosed in anther sacs;

viscidia orbiculate;

ovary slender to rather stout, mostly 16–29 mm.

resupinate, showy, rose-purple;

lateral sepals somewhat reflexed;

petals oblong-linear to spatulate, distally crenate to entire;

lip descending to somewhat porrect, deeply 3-lobed, without basal thickening, 11–20 × 12–23 mm, distal margins of lobes dentate-lacerate, rarely nearly entire, lateral lobes narrowly cuneate, middle lobe broadly cuneate-flabellate, emarginate to 2-fid;

spur clavate, 20–30 mm;

rostellum lobes directed forward, spreading, angular;

pollinaria straight to geniculate;

pollinia directed forward;

viscidia orbiculate;

ovary slender, 13–23 mm.

Platanthera macrophylla

Platanthera peramoena

Phenology Flowering Jun–Aug. Flowering (Jun–)Jul–Aug(–Oct).
Habitat Mesic to wet coniferous and deciduous forest Alluvial forests, wet wooded flats, stream banks, seeping slopes, marshes, moist prairies, old fields and pastures, ditches, thickets
Elevation mostly 0–1000 m (mostly 0–3300 ft) 0–800 m (0–2600 ft)
Distribution
from FNA
CT; MA; ME; MI; MN; NH; NY; PA; VT; NB; NL; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DE; GA; IL; IN; KY; MD; MO; MS; NC; NJ; OH; PA; SC; TN; VA; WV
[WildflowerSearch map]
Source FNA vol. 26. FNA vol. 26, p. 565.
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. nivea, P. obtusata, P. orbiculata, P. peramoena, P. praeclara, P. psycodes, 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. orbiculata, P. praeclara, P. psycodes, P. purpurascens, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
Synonyms Habenaria macrophylla, P. orbiculata var. macrophylla Habenaria peramoena
Name authority (Goldie) P. M. Brown: Wild Fl. Notes 3: 23. (1988) (A. Gray) A. Gray: Manual, 473. (1848)
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