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Lamiaceae
See list of 35 genera in this family-
1a. Calyx with a small, but evident, tranverse ridge on the upper side, the upper lip deciduous in fruit [Fig. 704]
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1b. Calyx without a protuberance on the upper side, persistent in fruit
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2a. Corolla apparently composed of a lower lip only, the upper lip either very small or displaced and part of the lower lip [Figs. 690,706]
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3a. Lower lip 5-lobed, the 2 small, lateral lobes representing the laterally displaced lobes of the upper lip; inflorescence elongate, raceme-like, 5–20 cm tall, leafy-bracted only at the base
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3b. Lower lip 3- or 4-lobed, the upper lip present, but very small; inflorescence either of verticillasters in the axils of foliage leaves or of flowers in leafy-bracted, spike-like inflorescences 4–8 cm tall
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2b. Corolla either clearly zygomorphic and with an evident upper and lower lip or nearly actinomorphic [Figs. 691,694,698]
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4a. Flowers with only 2 stamens, the other 2 stamens absent or represented by small staminodes (caution: the pollen sacs are separated by a connective in Salvia, creating the appearance of 4 anthers in some species) [Figs. 692,698]
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5a. Corolla yellow to pale yellow, the distal margin of the lower lip fringed [Fig. 692]; inflorescence a terminal panicle
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5b. Corolla white, ochroleucous, pink, red to purple, or blue (yellow and spotted with purple in Mondarda punctata), lacking a prominently fringed lower lip; inflorescence of verticillasters in axils of foliage or bracteal leaves, sometimes the verticillasters congested to form a dense cluster of flowers
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6a. Calyx strongly zygomorphic; corolla blue to purple-blue (often pale blue to pale purple in Blephilia, which has red-purple to purple spots)
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7a. Verticillasters with pedicellate flowers in the axils of foliage leaves; corolla 3–4 mm long
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7b. Verticillasters with sessile or short-pedicellate flowers in the axils of reduced, bract-like leaves, sometimes congested and forming terminal clusters of flowers; corolla 8–30 mm long
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8a. Inflorescence usually composed of 5–18 or more separate verticillasters of flowers; anthers attached to a narrow connective that is articulated to the filament, the upper end of the connective bearing a single pollen sac, the lower end of the connective either with a deformed pollen sac or without a pollen sac
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8b. Inflorescence composed of 1–5 closely crowded verticillasters of flowers, collectively forming dense, terminal clusters; anthers without a narrow connective, with 2 pollen-bearing sacs that are contiguous
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6b. Calyx actinomorphic or nearly so; corolla white, ochroleucous, pink, or red to purple (often blue-purple in Monarda fistulosa)
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9a. Corolla white, weakly zygomorphic, 1.8–4.4 mm long; flowers in dense but separate verticillasters in the axils of foliage leaves
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9b. Corolla only rarely white, strongly zygomorphic, 15–45 mm long; flowers in dense, crowded verticillasters at the tips of the stems and branches [Fig. 701], sometimes also in dense, axillary clusters
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10a. Basal, connate portion of the corolla (i.e., the tube) longer than and somewhat concealing the stamens
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11a. Inflorescence terminal, spike-like, the flowers subtended by reduced, bract-like leaves and separated by conspicuously shortened internodes relative to the vegetative portion of the stem; leaf blades linear to oblong or lanceolate
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12a. Corolla blue to purple, exceeding the calyx in lenth; calyx lobes without awns, the upper lobe with a obcordate appendage at the apex; plants woody near the base
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12b. Corolla yellow or black to dark red-brown with yellow on the lower lip, shorter than to approximately equaling the calyx; calyx lobes with prominent awns 1–2 mm long, the upper lobe lacking an appendage; plants herbaceous throughout
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11b. Inflorescence axillary, composed of few to many flowers in the axils of foliage leaves and separated by internodes of normal length (only the uppermost flowers with reduced bracts and/or internodes); leaf blades broad-elliptic to cordate-reniform
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13a. Stems conspicuously white-tomentose; corolla white; lobes of the calyx numbering 10, with reflexed and spinulose apices; plants from a taproot
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13b. Stems retrorse-scabrous, hirsute, or glabrous; corolla blue-purple; lobes of the calyx numbering 5, awned at the apex; plants from rhizomes and stolons (in part)
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10b. Basal, connate portion of the corolla shorter than the stamens, the stamens readily visible during anthesis [Figs. 693,705]
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14a. Inflorescence axillary, composed of few to many flowers in the axils of foliage leaves and separated by internodes of normal length (only the uppermost flowers with reduced bracts and/or internodes) [Fig. 700]
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15a. Calyx actinomorphic or nearly so
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16a. Corolla nearly actinomorphic, the 4 or 5 lobes nearly equal in length (i.e., not bilabiate; the upper lobe slightly wider than the others and often emarginate at the apex in Mentha)
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17a. Each verticillaster with numerous, crowded flowers; corolla with usually 4 lobes, the upper usually emarginate; ovary lobed to the point of appearing as 4 nearly distinct segments (in part)
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17b. Each verticillaster with 2–6 loosely disposed flowers; corolla with 5 lobes; ovary lobed, but the segments clearly connate ca. ⅓ their length (in part)
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16b. Corolla zygomorphic, definitely bilabiate
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18a. Flowers with short pedicels
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19a. Stems prostrate or trailing; each flower bearing axil with (2–) 3 flowers; upper pair of stamens longer than the lower pair (in part)
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19b. Stems erect; each flower-bearing axil with 4–8 flowers; upper pair of stamens shorter than the lower pair
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18b. Flowers sessile or subsessile
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20a. Principal leaf blades palmately lobed; corolla 8–12 mm long, the upper lip conspicuously villous
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20b. Leaf blades simple; corolla 10–30 mm long, the upper lip glabrous or sparsely pilose
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21a. Apex of sepals terminated by short, stiff spines; anthers dehiscing by latitudinal valves; mericarps broad-obovoid, rounded at the apex; lower lip of the corolla with a pair of projections near the sinuses on the adaxial (i.e., upper) surface [Fig. 694] (in part)
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21b. Apex of sepals acuminate, but not spiny; anthers dehiscing by longitudinal valves; mericarps three-angled, truncate or subtruncate at the apex; lower lip of the corolla without a pair of projections near the base of the lobes (in part)
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15b. Calyx zygomorphic, with an upper and lower lip
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22a. Corolla 4-lobed, nearly actinomorphic, the upper lobe slightly wider than the others and often emarginate at the apex (rarely with 5 subequal lobes) (in part)
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22b. Corolla zygomorphic, definitely bilabiate
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23a. Upper calyx lip with broad-triangular lobes, the lobes wider than long; corolla white or yellow (rarely becoming pink), the connate portion curved upward; leaf blades ovate to deltate-ovate; plants citrus-scented
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23b. Upper calyx lip with narrow-triangular lobes, the lobes longer than wide; corolla pale purple, red-purple, or pink (rarely white), the connate portion straight; leaf blades ovate, elliptic, oblong, or narrower; plants without a citrus scent (in part)
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14b. Inflorescence terminal or axillary, spike-like, raceme-like, or panicle-like, the flowers subtended by reduced, bract-like leaves and/or separated by conspicuously shortened internodes relative to the vegetative portion of the stem
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24a. Inflorescence an open, panicle-like cyme
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25a. Stamens with arcuate-curved filaments [Fig. 707]; leaf blades linear to rhombic-lanceolate; ovary lobed but the segments clearly connate ca. ⅓ their length (in part)
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25b. Stamens relatively straight; leaf blades elliptic or ovate to broad-ovate; ovary lobed to the point of appearing as 4 nearly distinct segments
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24b. Inflorescence spike-like (sometimes capitate) or raceme-like
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26a. Each node of the inflorescence with 2 flowers, 1 each in the axil of a bract
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27a. Leaf blades lanceolate or oblanceolate to elliptic, 1–2.5 cm wide, green; petioles absent on all but the lowest leaves; corolla (14–) 16–35 mm long
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27b. Leaf blades ovate-oblong to broad-ovate, 2.8–10 cm wide, tinged or suffused with purple; petioles 30–50 mm long; corolla 3–4 mm long
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26b. Each node of the inflorescence with 4 or more flowers
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28a. Upper lip of the corolla concavely arched, appearing as a small hood (i.e., the corolla galeate) [Figs. 695,705]
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29a. Apex of sepals terminated by short, stiff spines; anthers dehiscing by latitudinal valves; lower lip of the corolla with a pair of projections near the sinuses on the adaxial (i.e., upper) surface [Fig. 694] (in part)
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29b. Apex of sepals acuminate, but not spiny; anthers dehiscing by longitudinal valves; lower lip of the corolla without a pair of projections near the base of the lobes
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30a. Calyx zygomorphic; filaments bifid near the apex, the lower of the tooth-like branches bearing the anther; floral bracts broadly rounded at the apex
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30b. Calyx actinomorphic or nearly so; filaments not bifid at the summit; floral bracts obtuse to acuminate at the apex
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31a. Inner (i.e., upper) pair of stamens slightly to noticeably longer than the outer pair; calyx with 15 nerves
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32a. Corolla 8–12 mm long, usually spotted on the lower lip; upper and lower pair of stamens ± parallel, both ascending under the upper lip of the corolla; anther sacs divergent
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32b. Corolla 4–9 mm long, unspotted; upper pair of stamens (i.e., the longer pair) downwardly directed, the lower pair of stamens upwardly oriented; anther sacs ± parallel (in part)
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31b. Inner pair of stamens slightly shorter than the outer pair; calyx with 5 or 10 nerves
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33a. Median portion of inflorescence with conspicuously reduced bracteal leaf blades compared with the upper vegetative leaves; mericarps ovoid or obloid, rounded to obtusely pointed at the apex
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33b. Median portion of the inflorescence with scarcely reduced bracteal leaf blades compared with the upper vegetative leaves; mericarps three-angled, truncate or subtruncate at the apex (in part)
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28b. Upper lip of the corolla flat or upwardly curved, not hood-like [Fig. 691]
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34a. Stamens, at least the longer pair, upwardly curved, closely ascending under the upper corolla lip and not surpassing it [Fig. 691]
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35a. Uppermost lobe of the calyx wider than the other 4; calyx with 15 nerves; floral bracts spinose-serrate at least near the base (entire in D. thymiflorum)
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35b. Upper 3 lobes of the calyx differing from the other 2; calyx with 10–13 nerves; floral bracts entire to crenate-serrate
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36a. Corolla 5–7 mm long; leaf blades linear to narrow-oblanceolate; each flower subtended by minute bracts shorter than the calyx; plants annual, without stolons, 1–3 dm tall
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36b. Corolla 12–15 mm long; leaf blades narrow-ovate or ovate to ovate-oblong; each flower subtended by ciliate, linear-subulate bracts about as long as the calyx; plants perennial from short stolons, 2–5 dm tall (in part)
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34b. Stamens individually straight or nearly so, at least the longer pair protruding from the corolla (except in carpellate plants of Mentha, which have smaller flowers and included anthers) [Fig. 693]
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37a. Middle lobe of upper calyx lip suborbicular, with winged margins that are decurrent on the calyx tube, forming a concave cap over the top of the calyx; corolla with a 4-lobed upper lip and a single-lobed lower lip
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37b. Middle, upper lobe of the calyx subulate to triangular, not forming a cap over the entire calyx; corolla nearly actinomorphic or zygomorphic and then with a 3-lobed lower lip
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38a. Leaf blades with entire margins
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39a. Plants diffusely branched, mat-forming; leaf blades 5–10 mm long; calyx pubescent inside the connate tube
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39b. Plants upright; leaf blades 10–95 mm long; calyx ± glabrous inside the connate tube
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40a. Calyx 10- to 13-nerved; anthers with parallel pollen sacs; verticillasters with densely crowded flowers, forming capitate cymes at the apex of the stems and branches (in part)
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40b. Calyx 15-nerved; anthers with divergent pollen sacs; verticillasters with 3–7 flowers in the axils of bracts, forming a terminal, spike-like inflorescence
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38b. Leaf blades with toothed margins
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41a. Inflorescence secund [Fig. 693]; anthers with divergent pollen sacs; plants annual, without rhizomes
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41b. Inflorescence not secund; anthers with ± parallel pollen sacs; plants rhizomatous perennials (sometimes from a woody caudex in Agastache)
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42a. Corolla nearly actinomorphic, the lower lip unspotted (in part)
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42b. Corolla zygomorphic, the lower lip spotted with purple in commonly observed species
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43a. Calyx 15-nerved; upper lip of corolla somewhat convex and subgaleate; lower lip of corolla unspotted (in part)
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43b. Calyx 10- to 13-nerved; upper lip of corolla relatively flat or upwardly curved, not forming a hood; lower lip of corolla commonly spotted with purple (in part)
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Each photo represents one genus in this family.