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Orobanchaceae
See list of 12 genera in this family-
1a. Plants without chlorophyll, the stems yellow to brown or purple; leaf blades reduced to scales; ovary unilocular, with parietal placentation
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2a. Stems branched, usually many times; flowers dimorphic—the upper with a well-developed corolla and appearing bisexual, the lower carpellate with a small and unopening corolla that is forced off by the developing ovary; plants parasitic on Fagus
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2b. Stems simple or rarely few-branched; flowers monomorphic; plants parasitic on various species of plants
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3a. Calyx with 5 subequal lobes or with 2 lateral lobes separated by a deep apical and basal sinus and each lobe usually bifurcate (therefore, the calyx usually 4 lobed); stems either subterranean or above-ground and sparsely leafy
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3b. Calyx tubular and irregularly toothed, split by a deep basal sinus only; stems above-ground and ± concealed by overlapping leaves
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1b. Plants with chlorophyll, with green stems and/or leaves in life; leaf blades foliaceous [Figs. 752,754]; ovary bilocular, with axile placentation
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4a. Foliage leaves of the stem alternate [Fig. 750]; anthers glabrous (sparsely pubescent near apex in Schwalbea)
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5a. Flowers subtended by a pair of bractlets situated at the base of the calyx; calyx with 5 lobes
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5b. Flowers without a pair of bractlets; calyx with 2 or 4 lobes (5 lobes in Pedicularis furbishiae)
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6a. The two anther sacs on each filament similar; corolla 2 or more times as long as the calyx; bracts herbaceous (in part)
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6b. The two anther sacs on each filament dissimilar—one attached to the filament near its middle, the other suspended from near its apex; corolla less than 2 times as long as the calyx; bracts petaloid
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4b. Foliage leaves of the stem opposite [Fig. 754]; anthers pubescent (glabrous in Odontites)
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8a. Corolla yellow (sometimes marked with brown or red-brown), 25–50 mm long; leaf blades evidently lobed; capsules ovoid to ellipsoid, acute at the apex; anther locules awned at the base
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8b. Corolla pink to purple (rarely white), 10–20 mm long; leaf blades entire; capsules globose to subglobose, rounded at the apex (except sometimes for a mucro); anther locules obtuse to cuspidate at the base
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7b. Corolla zygomorphic and galeate (i.e., with an upper, hooded lip that invests the stamens) [Figs. 753,754], 2.5–14 mm long
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9a. Leaf and bract blades palmately veined; corolla white, blue, or purple, usually with darker purple lines, the sides of the upper lip reflexed
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9b. Leaf and bract blades pinnately veined; corolla white, yellow, or red, the sides not reflexed
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10a. Corolla yellow; calyx laterally compressed (i.e., taller than thick), with 2 prominent lateral lobes separated by a deep apical and basal sinus (each lateral lobe bifurcate in Rhinanthus) [Fig. 754]
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11a. Each lateral half of the calyx bifurcate (i.e., with 4 total lobes), without foliaceous appendages; calyx accrescent in fruit and becoming very inflated; fruit symmetrical, dehiscing evenly
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11b. Lateral halves of calyx unlobed, tipped by a foliaceous appendage; calyx not accrescent in fruit; fruit asymmetrical, dehiscing only or more prominently on the upper side (in part)
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10b. Corolla red or both white and yellow; calyx not laterally compressed, subequally 4-lobed
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12a. Corolla red, pubescent; anthers glabrous; capsule shorter than the persistent calyx, with more than 4 seeds
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12b. Corolla white with a yellow palate, glabrous; anthers pubescent; capsule longer than the persistent calyx, with 1–4 seeds
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Show photos of:
Each photo represents one genus in this family.