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Ribes
See list of 12 species in this genusRibes oxyacanthoides L. was reported from ME by Campbell et al. (1995); however, the supporting specimens (at MAINE!) were all R. hirtellum, as evidenced by stamens exceeding the petals, cuneate to truncate leaf blade bases, and absence of internodal prickles. References: Sinnott (1985), Morin (2009).
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1a. Inflorescence a raceme, with (3–) 4–20 or more flowers [Figs. 674,676]; pedicels articulated at the summit, the fruits falling from them; branchlets unarmed (armed in R. lacustre)
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2a. Ovary and fruit pubescent with bristly, gland-tipped hairs [Fig. 676]
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3a. Stems with thin prickles; racemes spreading to drooping; petals broad-flabellate to orbicular; berries purple or black
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3b. Stems unarmed; racemes ascending to erect [Fig. 676]; petals cuneate-obovate; berries dark red
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2b. Ovary and fruit glabrous or with sessile, resinous glands [Fig. 674]
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4a. Hypanthium above the ovary tubular, 9–15 mm long; sepals gold-yellow; mature leaf blades 20–35 (–50) mm long, each lobe with 0–3 (–7) apical teeth
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4b. Hypanthium above the ovary campanulate or scutelliform, up to 4.5 mm long; sepals green-purple or green-white to yellow; mature leaf blades (25–) 30–90 mm long, abundantly toothed, the teeth not restricted to the apical portion of the lobe
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5a. Leaf blades, winter buds, and branchlet apices resin-dotted [Fig. 674]; berries black; hypanthium above the ovary cupuliform
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6a. Pedicels 0.1–2 mm long, much exceeded by the conspicuous, lanceolate bracts [Fig. 674]; racemes with 6–15 flowers; calyx lobes glabrous or very sparsely pubescent on the abaxial surface; ovary without resin glands; branchles with prominent decurrent ridges extending from the nodes that are noticeably raised above the branch surface, without a fetid odor when bruised
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6b. Pedicels 2–8 mm long, much longer than the minute, ovate bracts; racemes with 4–10 flowers; calyx lobes pubescent on the abaxial surface; ovary with at least a few sessile resin glands; branchles with obscure decurrent ridges that are barely raised above the branch surface, with a fetid odor when bruised
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5b. Leaf blades, winter buds, and branchlet apices without resin glands; berries red (rarely translucent white in R. rubrum); hypanthium above the ovary scutelliform
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7a. Axis of raceme and pedicels stipitate-glandular; anther sacs adjacent to one another; lateral leaf lobes commonly directed forward; terminal leaf lobe deltate; calyx lobes green-purple; stems straggling to ascending
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7b. Axis of raceme and pedicels without glands; anther sacs widely separated by a broad connective; lateral leaf lobes spreading; terminal leaf lobe ovate; calyx lobes yellow to green; stems ascending to erect
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1b. Inflorescence a solitary flower or a corymb-like cluster of 2–4 (–5) flowers [Fig. 675]; pedicels not articulated at the summit, the fruits remaining on them; branchlets often armed with slender prickles and/or bristles, especially at the nodes
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8b. Berry glabrous, glandular, or bristly, but without prickles, the ovary not stipitate-glandular during flowering (except usually in R. uva-crispa); tubular portion of the hypanthium above the ovary equaling or shorter than the calyx lobes
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9a. Flowers in anthesis with stamens evidently longer than the sepals; peduncles 5–20 mm long; styles 7–14 mm long
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10a. Stamens 6–8 mm long; hypanthium purple to green-purple; calyx lobes 4–5 mm long; nodal prickles 2–5 (–11) mm long
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10b. Stamens 9–12 mm long; hypanthium white to cream-white; calyx lobes 5–7.5 mm long; nodal prickles 7–17 mm long
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9b. Flowers in anthesis with stamens shorter than to barely longer than the sepals; peduncles 2–6 mm long; styles 2.5–8 mm long
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11a. Hypanthium, sepals, and berry pubescent (often also with some gland-tipped bristles); sepals 5–7 mm long, round-obovate; nodal prickles stout, 10–15 mm long
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11b. Hypanthium, sepals, and fruit glabrous (rarely the hypanthium and fruit sparsely pubescent); sepals 3–4 mm long, oblong to broad-oblong; nodal prickles slender, 3–8 mm long
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Each photo represents one species in this genus.