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Apiaceae
See list of 45 genera in this familyThe concept of an expanded Apiaceae (i.e., one that includes the Araliaceae) has always been challenged. However, recognition of a monophyletic Araliaceae s.s. forces inclusion of some “Apioid” genera within the Araliaceae, and also requires recognition of the Myodocarpaceae, an Australasian group that combines morphological characters of both the Apiaceae and Araliaceae. In light of such evidence, one inclusive family is recognized here—Apiaceae. Schizocarp compression is an important morphological character in this family. How compression is referenced varies by author. Those species that have schizocarps compressed parallel to the commissure are sometimes referred to as “dorsally compressed.” Those species that have schizocarps compressed perpendicular to the commissure are sometimes referred to as “laterally compressed.”
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1a. Gynoecium with 2–5 carpels, maturing as a drupe or a berry with 2–5 pyrenes or seeds, respectively; plants woody or herbaceous
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2a. Plants lianas, with aerial roots; leaves evergreen
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2b. Plants trees, shrubs, or herbs, without aerial roots; leaves deciduous
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3a. Leaf blades 2 or more times pinnately divided; gynoecium with usually 5 carpels, therefore, the fruit with 5 pyrenes
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3b. Leaf blades palmately lobed or once palmately divided; gynoecium with 2 or 3 carpels, therefore, the fruit with 2 or 3 pyrenes or seeds (up to 5 carpels and seeds in Eleutherococcus)
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4a. Plants herbaceous, unarmed, with a single whorl of leaves near the summit of the stem; petals imbricate in bud; styles distinct
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4b. Plants woody, armed, with many alternate leaves; petals valvate in bud; styles basally connate
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5a. Leaf blades palmately lobed; petiole 8–50 cm long
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5b. Leaf blades palmately divided; petiole up to 12 cm long
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1b. Gynoecium with 2 carpels, maturing as schizocarp that separates into 2 mericarps; plants herbaceous
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6a. Inflorescence composed of dense, head-like clusters of ± sessile flowers [Fig. 349], each flower subtended by a bractlet; most leaf blades spinulose-toothed
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6b. Inflorescence dense to open, with pedicellate flowers (sessile in some Hydrocotyle) [Fig. 347],
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7a. Bractlets of umbel connate basally, white to pink, usually equal to or longer than the umbel they subtend; schizocarps covered with bladdery, triangular scales
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7b. Bractlets of umbel (when present) distinct, green, and/or shorter than umbel, commonly with all three traits; schizocarps without scales (though sometimes with hairs, bristles, or prickles)
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8a. Umbels simple [Fig. 351]; stems prostrate, creeping over the substrate
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9a. Leaves with orbicular to ovate-orbicular blades, the blades crenate to inconspicuously lobed, not hollow, without septa [Fig. 351]
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9b. Leaves phyllodial, linear, entire, hollow, each with 4–6 transverse septa
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10a. Stem leaves simple and entire
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10b. Stem leaves divided (simple and toothed in the tidal form of Sium suave)
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11b. Leaf blades compound to decompound; plants mostly synoecious (polygamous in Taenidia); ovary and fruit glabrous or provided with hairs, bristles, or prickles, but these not hooked at the tip (except in Torilis)
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12a. Ovary and fruit pubescent, bristly, or prickly
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13a. Ultimate segments of leaf blades narrow-linear to filiform, up to 1 mm wide, all entire
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13b. Ultimate segments of leaf blades linear to ovate or obovate, wider than 1 mm, often toothed
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14a. Bractlets at base of umbellets bilobed at apex; mericarp with a quadrangular body 6–15 mm long, tipped by an elongate, flattened beak 20–70 mm long
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14b. Bractlets simple or pinnately dissected or absent; mericarps 2–20 mm long, without a beak or with a short, inconspicuous beak 1–2 mm long
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15a. Bracts of inflorescence pinnately dissected [Fig. 348]; central flower of inflorescence usually purple
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15b. Bracts of inflorescence simple or absent; central flower of inflorescence white, colored similar to the other flowers
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16a. Inflorescence with 15–150 primary branches; upper leaf sheaths dilated, wider than 10 mm; schizocarps strongly compressed parallel with the commissure
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17a. Principal leaf blades once divided into 3 (rarely as many as 7) segments [Fig. 350], the segments again lobed and 5–30 (–60) cm long; schizocarp 7–12 mm long, with promiment oil tubes (in part)
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17b. Principal leaf blades 2 or 3 times pinnately compound, the ultimate segments 2–4 (–7) cm long; schizocarp 4–7 mm long, with inconspicuous oil tubes (in part)
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16b. Inflorescence with 2–15 (–20) primary branches; upper leaf sheaths not conspicuously dilated and narrower than 10 mm; schizocarps weakly compressed perpendicular to the commissure
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18a. Ultimate segments of leaf blades narrower than 10 mm; ovary and fruit with stiff, thin, ascending to spreading prickles [Fig. 358]
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18b. Ultimate segments of leaf blades wider than 10 mm; ovary and fruit with hairs or appressed-ascending bristles [Figs. 352,353]
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19b. Principal leaf blades simple to once pinnately compound; schizocarps 3–5 mm long, ovate in outline (in part)
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12b. Ovary and fruit glabrous
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20a. Principal stem leaf blades with ultimate segments wider than 10 mm, frequently wider than 15 mm, the segments clearly recognizable and often of uniform shape, not further dissected into narrow lobes
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21a. Upper leaf sheaths dilated, wider than 10 mm [Fig. 350]; inflorescence with 15–150 primary branches
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22a. Principal leaf blades once divided into 3 (rarely as many as 7) segments [Fig. 350], the segments again lobed and 5–30(–60) cm long; marginal flowers of umbel enlarged, zygomorphic, the outer petals often bifid (in part)
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22b. Principal leaf blades 2 or 3 times pinnately compound, the ultimate segments 2–4(–7) cm long; marginal flowers of umbel not or only slightly enlarged, actinomorphic, the outer petals usually entire (in part)
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21b. Upper leaf sheaths not dilated, narrower than 10 mm; inflorescences with 2–25(–30) primary branches
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23a. Schizocarp 1.5–2 mm long; umbels mostly sessile or shortly pedunculate from the axils of leaves (some terminal ones with evident peduncles also present)
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23b. Schizocarp 2–10 mm long; umbels, whether lateral or terminal, mostly with evident peduncles
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24a. Principal leaf blades with 3 leaflets, the leaflets sometimes with conspicuous lobes but not again divided (the basal leaves with simple blades in Thaspium)
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25a. Flowers with white petals and minute sepals; primary branches of umbel distinctly unequal in length [Fig. 347]; basal leaf blades compound; schizocarp 5–8 mm long
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25b. Flowers with purple petals and small, but evident, sepals; primary branches of umbel ± equal in lengh; basal leaf blades simple; schizocarp 3.5–5 mm long
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24b. Principal leaf blades with more than 3 leaflets
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26a. Principal leaf blades (or the emersed ones in Sium) once pinnately compound
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27a. Basal leaf blades simple, cordate at base; central flower of each umbellet sessile, the others pedicelled; stylopodium wanting (in part)
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27b. Basal leaf blades compound (simple in a tidal form of Sium suave); all the flowers pedicellate; stylopodium present
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28a. Petals yellow; schizocarp conspicuously compressed parallel to the commissure [Fig. 354], with conspicuous lateral wings much wider than the abaxial ribs (in part)
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28b. Petals white; schizocarp weakly compressed perpendicular to the commissure [Fig. 357], the lateral ribs not evidently wider than the abaxial ribs
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29a. Leaflets of emersed leaves linear to narrow-ovate, with veins not consistently directed to teeth or sinuses; bractlets at base of umbellets present; native plants of wetlands, when submersed with bi- or tri-pinnately dissected lower leaf blades
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29b. Leaflets ovate to suborbicular, the veins generally directed to the tips of teeth or lobes; bractlets at base of umbellets usually absent; introduced plants of fields and disturbed ground, not producing highly dissected blades (in part)
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26b. Principal leaf blades two or three times pinnately compound
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30a. Leaflets entire; umbellets near margin of inflorescence bearing bisexual flowers around the periphery and staminate flowers toward the middle, the umbellets near the center of the inflorescence entirely staminate
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30b. Leaflets toothed; umbellets not varying as to sex of flowers
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31a. Central flower of each umbellet sessile, the others pedicelled; stylopodium wanting (in part)
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31b. All the flowers pedicelled; stylopodium present
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32a. Central rachis of leaf prominently foliaceous-winged below the terminal triad of leaf segments
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32b. Central rachis of leaf not wing-margined
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33a. Veins of the leaf blade segments directed to the sinuses [Fig. 346]; stems hollow and cross-septate near the base; sepals well-developed, triangular (in part)
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33b. Veins of the leaf blade segments mostly directed to the tips of the teeth or lobes; stems solid or hollow at base, but without cross septa; sepals minute or obsolete (present in Ligusticum)
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34a. Ultimate segments of leaf blades usually entire in the basal ⅓ to ½; bractlets at base of umbellet mostly numbering 6–10
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35a. Petals yellow to green-yellow; sepals obsolete; schizocarp conspicuously compressed parallel to the commissure; introduced plants of fields and disturbed ground
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35b. Petals white; sepals well-developed, triangular; schizocarp weakly compressed perpendicular to the commissure; native plants of Atlantic coast beaches
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34b. Ultimate segments of leaf blades ± uniformly serrate or serrulate; bractlets at base of umbellet absent or few (present in Angelica lucida)
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36a. Upper leaf sheaths diliated, wider than 10 mm; umbels with 18–50 primary branches; native plants (in part)
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36b. Upper leaf sheaths not dilated, narrower than 10 mm; umbels with 12–25 primary branches; introduced plants, sometimes invasive
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37a. Petals yellow; schizocarp 5–7 mm long, conspicuously compressed parallel to the commissure [Fig. 354], with deciduous or inconspicuous styles (in part)
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37b. Petals white; schizocarp 3–4 mm long, compressed perpendicular to the commissure, with persistent, reflexed styles extending back to near midlength of fruit [Fig. 344]
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20b. Principal stem leaf blades with ultimate segments narrower than 10 mm (frequently narrower than 6 mm), the segments less organized and the limits of each not always obvious
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38a. Ultimate segments of leaf blades narrow-linear to filiform, up to 1 mm wide, all entire (the lower leaves in Coriandrum with broader segments); mature schizocarps spicy or pleasantly aromatic (except Bifora and Ptilimnium)
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39a. Bracts at base of primary umbel often pinnately divided into filiform segments; sepals present, ± equal in size; native plants of saline marshes
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39b. Bracts at base of primary umbel absent or present and simple; sepals none or present in Coriandrum and then distinctly unequal in size; spice plants escaped from cultivation ( Bifora foliage unpleasantly aromatic)
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40a. Petals yellow; umbel with (10–) 15–40 primary branches; styles short and stout in anthesis, up to 0.5 mm long excluding stylopodium; bractlets at base of umbellets absent
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41a. Principal leaves with petiolar sheaths 1–2.5 (–3) cm long; schizocarp compressed parallel with commissure, with prominent lateral wings; plants annual
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41b. Principal leaves with petiolar sheaths 3–9 (–10) cm long; schizocarp subterete or slightly compressed perpendicular to the commissure, the lateral wings no more prominent than those of the abaxial surface; plants short-lived perennial
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40b. Petals white to pink; umbel with 3–14 (–16) primary branches; styles slender, 0.5–2 mm long excluding stylopodium; bractlets (at least 1) usually present at base of umbellets
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42a. Schizocarp nearly biglobose, each mericarp subglobose, faintly rugulose-patterned; umbel with 3–8 primary branches
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42b. Schizocarp not biglobose, each mericarp hemispherical or narrower, ridged or ribbed, but not rugulose; umbel commonly with 8 or more primary branches or less in Coriandrum, but that species with the lower leaf blades merely lobed with relatively broad segments
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43a. Umbel with 3–7 (–8) primary branches; schizocarp subglobose, tardily separating; marginal flowers of umbel with sepals and conspicuously enlarged petals 3–4 mm long
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43b. Umbel with (6–) 8–14 (–16) primary branches; schizocarp oblong to elliptic in outline, readily separating into 2 mericarps; marginal flowers of umbel ± similar to the central ones, without sepals and with petals not over 2 mm long
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38b. Ultimate segments of leaf blades linear to ovate or obovate, wider than 1 mm, often toothed; mature schizocarps rank-scented or weakly aromatic (strongly aromatic in Myrrhis)
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44a. Schizocarps 15–25 mm long; primary branches of umbel dimorphic (especially in fruit), those bearing only staminate flowers thinner and shorter than those bearing bisexual flowers
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44b. Schizocarps 1.5–10 mm long; primary branches of umbel ± monomorphic
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45a. Schizocarp with a smooth body, lacking ribs or wings (only the apical beak ribbed in A. sylvestris) [Fig. 345]; bractlets at base of umbellets narrow-ovate (linear in A. cerefolium), with conspicuously ciliate or fimbriate margins
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45b. Schizocarp with a ribbed and/or winged body; bractlets setaceous to lanceolate, not or only minutely ciliate, or absent
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46a. Plants bearing vegetative bulbils on the upper parts, these subtended by broad-based, acuminate-tipped bracts (in part)
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46b. Plants without bulbils
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47a. Stems spotted with red-purple; bractlets subtending the umbellets lanceolate to ovate or triangular, conspicuously wider than the pedicels they subtend
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47b. Stems not spotted with red-purple; bractlets setaceous to narrow-lanceolate or narrow-oblanceolate, scarcely, if at all, wider than the pedicels they subtend (narrow-lanceolate to lanceolate and somewhat wider in Peucedanum)
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48a. Petals yellow to green-yellow; schizocarp somewhat compressed perpendicular to the commissure, with thin ribs narrower than the intervals between them
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48b. Petals white; schizocarp subterete or conspicuously compressed parallel to the commissure, the thick ribs wider than the intervals between them
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49a. Primary branches of umbel very unequal, the outer branches 2–3 times (or more) longer than the central branches; outer flowers of umbel zygomorphic; schizocarp subterete
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49b. Primary branches of umbel only somewhat unequal, the outer branches shorter than to as much as 2 times as long as the central branches; outer flowers of umbel not or scarcely zygomorphic; schizocarp somewhat to conspicuously compressed parallel to the commissure
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50a. Schizocarp suborbicular in outline, with low, blunt abaxial ribs; bractlets subtending the umbellets narrow-lanceolate to lanceolate; stems hollow
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50b. Schizocarp elliptic to oblong or ovate-oblong in outline, with prominently raised, thin-edged, abaxial ribs; bractlets subtending the umbellets linear to narrow-lanceolate; stems solid
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51a. Branches of inflorescence glabrous; schizocarp (4.5–) 5–6 (–8) mm long; native plants of swamps, stream banks, and riparian forests
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51b. Branches of inflorescence puberulent on the angles; schizocarp 3–4 mm long; non-native plants of waste areas and yards
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Show photos of:
Each photo represents one genus in this family.