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Boraginaceae
See list of 22 genera in this familyReference: Johnston (1924).
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1a. Each carpel of the ovary with 2–many ovules; fruit a 2-valved capsule with 1–80 seeds; at least the lower leaf blades lobed or compound (entire to coarsely toothed in some Phacelia)
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2a. Flowers solitary in the axils of opposite the leaves; at least the lower leaves opposite; corolla 5–8 mm long, ± equaled or exceeded by the calyx
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2b. Flowers arranged in helicoid cymes or subdichotomously branched cymes; leaves alternate; corolla 7–12 mm long, exceeding the calyx
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3a. Inflorescence a subdichotomously branched cyme, lacking an elongate central axis; plants from fibrous roots
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3b. Inflorescence a helicoid cyme, with 1 or more elongate, sympodial axes; plants from taproots
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1b. Each carpel of the ovary with 2 ovules; fruit a schizocarp separating into (1–) 4 mericarps; leaf blades simple and mostly entire
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4a. Ovary unlobed or inconspicuously lobed; style terminating the summit of the ovary; stigma peltate-annular, surmounted by a cone-like process
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4b. Ovary with deep sinuses, appearing as 4 ± distinct carpels; style arising from between the lobes; stigma not peltate-annular
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5a. Corolla rotate [Fig. 492]; anthers 5–9 mm long, with conspicuous linear appendages ca. 3 mm long
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5b. Corolla tubular, funnelform, or salverform [Figs. 490,494,502]; anthers shorter, without appendages
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6a. Corolla weakly zygomorphic [Fig. 494], the tubular, connate portion sometimes also bent
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7a. Apex of corolla tube lacking fornices, the tube appearing open; stamens exserted beyond the corolla; mericarps without a stipe-like process, attaching directly to the receptacle; receptacle flat, without a pit
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7b. Apex of corolla tube with fornices, these appearing to close off the tube; stamens included within the corolla tube; mericarps attached to the receptacle by a stipe-like process, this fitting into a pit in the receptacle (in part)
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8a. Ovary and mericarps with barbed prickles, at least on the marginal or abaxial surfaces [Figs. 493,495]
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9a. Plants annual; each flower closely subtended by a bract
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9b. Plants biennial or perennial; all or most of the flowers without closely associated bracts
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10a. Corolla 5–8 mm wide; mericarps attached to one another by the apical third of their inner faces; mericarps 3.5–5 mm long
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10b. Corolla 2–3 mm wide; mericarps attached to one another along the middle third of their inner faces; mericarps 2–3 mm long
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8b. Ovary and mericarps smooth or textured, sometimes muricate, but never with barbed prickles
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11a. Stems retrorsely prickly hispid [Fig. 491], weak and scrambling; inflorescence axillary, of 1–3 flowers borne on short, recurved pedicels; calyx accrescent in fruit, becoming 10–20 mm wide, compressed, firm, and evidently reticulate-veiny, with dentate margins
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11b. Stems glabrous to hispid-pubescent, but not retrorsely prickly hispid, weak and sprawling to rigid and erect; inflorescence of 1 or more helicoid cymes or consisting of crowded flowers in the upper leaf axils in Lithospermum and Buglossoides; calyx not notably accrescent in fruit, ± circular in cross-section, not or scarcely veiny, with entire margins
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12a. Corolla yellow to orange, the apex of the tube without fornices (though the tube obstructed by pubescent bulges near the orifice in Amsinckia lycopsoides)
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12b. Corolla white, yellow-white, pink, red-purple, blue, purple, or brown (pale yellow in Symphytum tuberosum, with a yellow center in some Myosotis), the apex of the tube with fornices (lacking fornices in Buglossoides arvensis and Mertensia virginica)
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14a. Lower 1–4 nodes of the stem producing opposite leaves
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15a. Mericarp attachment scar grooved on inner median surface, the groove flaring open or forking at the base of the mericap, without a raised keel apical to the attachment scar; basal leaves usually present during early flowering (these early deciduous)
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15b. Mericarp with a raised attachment scar on the inner median surface, with a raised keel apical to the attachment scar; basal leaves absent, all leaves borne on the stem
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14b. Stem leaves all alternate
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17a. Leaf blades conspicuously white-spotted; stems with stipitate glands; tube of corolla obstructed by 5 tufts of hairs
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17b. Leaf blades without white spots; stems lacking stipitate glands; tube of corolla obstructed by 5 scales or lacking fornices altogether (with hairs at the base of the corolla tube in Nonea)
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18a. Leaf blades and stems glabrous; mericarps without a stipe-like process, attaching directly to the receptacle; receptacle flat, without a pit
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18b. Leaf blades and stems hispid-hirsute; mericarps attached to the receptacle by a stipe-like process, this fitting into a pit in the receptacle
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19a. Style exserted beyond the corolla; fornices present
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19b. Style not exserted beyond the corolla; fornices absent, the tube of the corolla obstructed by tufts of hairs
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20a. Flowers, except sometimes the lower, not subtended by bracts; corolla lobes convolute in bud (i.e., arranged so that one margin is exposed and the other margin covered by the adjacent petal); mericarps smooth
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20b. Flowers all or mostly all subtended by bracts; corolla lobes imbricate in bud (i.e., arranged so that the outer members have both margins exposed, the inner members have both margins covered); mericarps wrinkled or pitted, or smooth in Lithospermum
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21a. Limb of the corolla 7–15 mm wide; mericarps attached to the receptacle by a stipe-like process, this fitting into a pit in the receptacle (in part)
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21b. Limb of the corolla up to 4 mm wide; mericarps without a stipe-like process, attaching directly to the receptacle; receptacle flat, without a pit
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22a. Plants perennial; corolla 4–5 mm long; leaves with 2 or 3 conspicuous, lateral veins; mericarps lustrous, white to white-brown, smooth
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22b. Plants annual (rarely biennial); corolla 5–8 mm long; leaves without conspicuous, lateral veins; mericarps dull brown, wrinkled and pitted or roughened
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Each photo represents one genus in this family.