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Calystegia
See list of 4 species in this genusCalystegia hederacea Wallich has been reported from most states in New England by various authors. However, these reports actually refer to C. pubescens (see discussion under that species). Reference: Brummitt (1980).
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1a. Stems erect, only the tip twining; leaf blades broad-cuneate to subcordate at the base; leaves subtending the flowers with petioles less than 50% of the length of the leaf midvein, those of the basal portion of the plant conspicuously reduced; bracts subtending the calyx cuneate at the base
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1b. Stems twining or trailing; leaf blades sagittate to hastate at the base; leaves subtending the flowers with petioles more than 50% of the length of the leaf midvein, those of the basal portion of the plant only slightly reduced; bracts subtending the calyx rounded to cordate at the base
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2a. Sinus of leaf blade usually rectangular, the leaf tissue not beginning on the interior of the basal lobes for 2–5 (–10) mm from the petiole attachment [Fig. 588]; bracteoles rounded to obtuse at apex, saccate at the base [Fig. 588], overlapping; peduncles frequently paired at some nodes on the plant, not exceeding the leaves; corolla usually white
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2b. Sinus of leaf blade usually V-shaped or U-shaped, the leaf tissue beginning on the interior of the basal lobes 0–2 (–3) mm from the petiole attachment [Fig. 587]; bracteoles long-acute to obtuse at the apex, not or slightly saccate at the base [Fig. 587], not or scarcely overlapping; peduncles usually solitary, often equaling or exceeding the leaves; corolla white or pink
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3a. Flowers usually with stamens modified into a second cycle of petals; stems pubescent; petioles of proximal leaves 1–6 cm long
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3b. Flowers not modified, with a single series of connate petals; stems glabrous or pubescent in ssp. americana; petioles of proximal leaves (1.5–) 5–10 cm long
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Each photo represents one species in this genus.