The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

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

little club-spur bog-orchid, small green wood orchid

Habit Plants 23–63 cm. Plants 8–47 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.

1(–2), on basal half of stem, ascending to spreading, usually abruptly reduced to bracts distally;

blade oblanceolate to oblong, linear-oblong, or elliptic, 3–19 × 0.8–3.5 cm.

Spikes

lax.

moderately 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, often incompletely so and held at angle, not showy, rather inconspicuous pale green to dull yellowish green;

lateral sepals porrect;

petals ovate to obovate;

lip oblong, obscurely 3-lobed, without basal thickening, 3–7 × 3–4 mm, margins sometimes dentate-lacerate, apex truncate;

spur clavate, 7–13 mm;

rostellum lobes directed downward, very short, truncate;

pollinaria straight or slightly curved laterally;

pollinia fragmenting, pollen masses trailing down onto stigma;

viscidia linear to linear lanceolate;

ovary rather stout, 6–11 mm.

2n

= 42.

Platanthera macrophylla

Platanthera clavellata

Phenology Flowering Jun–Aug. Flowering summer (Jun–Aug).
Habitat Mesic to wet coniferous and deciduous forest Sphagnum bogs, sphagnous seeps and meadows, wet sandy and peaty meadows, marshes, low woods, wet prairies, and roadsides
Elevation mostly 0–1000 m (mostly 0–3300 ft) 0–2000 m (0–6600 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; CT; DC; DE; FL; GA; IA; IL; IN; KY; LA; MA; MD; ME; MI; MN; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; NB; NF; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

In common with Platanthera nivea and P. integra, the column of P. clavellata bears a series of lateral projections that are directed forward; the upper pair is elaborately adorned and may be glandular. It appears that this species is inappropriately placed in Platanthera. See note under 30. P. nivea

The broader leaves cited as distinguishing Platanthera clavellata var. ophioglossoides are more prevalent in the North, but occur throughout the range of the species. In some areas populations commonly display a complete range of leaf shape; this feature alone is of no taxonomic significance.

The unusual and infrequent hybrid Platanthera blephariglottis × P. clavellata is P. ×vossii Case.

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

Source FNA vol. 26. FNA vol. 26, p. 570.
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. 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. psycodes, P. purpurascens, P. sparsiflora, P. stricta, P. tipuloides, P. zothecina
Synonyms Habenaria macrophylla, P. orbiculata var. macrophylla Orchis clavellata, Habenaria clavellata, Habenaria clavellata var. ophioglossoides
Name authority (Goldie) P. M. Brown: Wild Fl. Notes 3: 23. (1988) (Michaux) Luer: Native Orchids Florida, 148. (1972)
Web links