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Sisyrinchium
See list of 6 species in this genusIdentification of Sisyrinchium requires examination of multiple ramets because occasional stems from a given genet will show an unusual character state. For example, it is possible to find “branched stems” among a clump of S. montanum, a species that normally displays “unbranched stems.” Reference: Cholewa and Henderson (2002).
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1a. Inflorescences, each of which is subtended by 2 opposed spathe bracts, paired at the summit of the stem and sessile (i.e., without peduncles); spathe bracts closely subtended and partly concealed by a bract-like leaf; tepals white or pale violet
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1b. Inflorescences either occurring singly at the summit or numbering 2–5 and then borne on branch-like peduncles; spathe bracts not closely subtended by leaves; tepals blue to purple (rarely pale blue or white)
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2a. Inflorescences sessile, usually solitary at the apex of the stem; stems appearing unbranched [Fig. 139]
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3a. Stems 0.9–1.5 (–2) mm wide, with scarcely discernible wing margins; spathes usually suffused with purple; pedicels usually spreading to recurving in fruit; tepals rounded to emarginate at apex
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3b. Stems (1.5–) 2–3.7 mm wide, with obvious wing margins; spathes usually green to bronze, rarely suffused with purple; pedicels usually erect to ascending in fruit; tepals emarginate to retuse at apex
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2b. Inflorescences pedunculate, usually 2–5 per stem; stems appearing branched due to long, branch-like peduncles [Fig. 138]
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4a. Stems 2.3–5 mm wide, broadly winged, sometimes with minutely denticulate margins, especially near the base; outer bract of the spathe mostly 18–38 mm long; plants dark olive-green to black-green in drying
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4b. Stems 0.8–1.9 mm wide, narrowly winged, with entire margins; outer bract of the spathe mostly 12–18 mm long; plants yellow-green to olive-green in drying
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5a. Leaf blades persisting as fibrous tufts at base of plant; ovary green, similar in color to foliage; capsule light to medium brown
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5b. Leaf blades not persisting as fibrous tufts; ovary dark brown to purple-black, in contrast to lighter foliage; capsule dark brown to purple-black
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Each photo represents one species in this genus.