keys to the vascular plants of east texas - Botanical Research ...

SISYRINCHIUM/IRIDACEAE
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3. Inflorescences usually paired (two pairs of spathe bracts borne in such close proximity that
1 pair often obscured), immediately subtended by a bract-like leaf much longer than the
spathe (this bract-like leaf so close as to be touching the spathe); flowers usually white, sometimes
light blue; stems without additional leaves other than those immediately subtending
inflorescences _________________________________________________________________ S. albidum
3. Inflorescences borne singly (each pair of spathe bracts clearly distinct from other pairs), not
immediately subtended by a leaf (the subtending leaf, if present, not touching spathe); flowers
white to light blue to blue-violet, purple-blue, or blue; stems with OR without leaves.
4. Stems unbranched (or most individuals of a population with unbranched stems), without
leaves/bract-like leaves other than paired bracts of the spathe.
5. Outer spathe bract with margins free or rarely basally connate 1 mm or less, 10–32 mm
longer than the inner spathe bract; tepals white to light blue _____________________ S. campestre
5. Outer spathe bract with margins basally connate for 1–6.1 mm, ca. equaling the inner
spathe bract in length to 13 mm longer than the inner spathe bract; tepals blue to
bluish violet.
6. Outer spathe bract 6.2–13 mm longer than inner; leaf bases becoming fibrous and
persisting in tufts; capsules ca. 3–4 mm long; plants drying dark brown to reddish
brown or brownish olive _______________________________________________ S. sagittiferum
6. Outer spathe bract ca. as long as inner; leaf bases not persistent in tufts; capsules 5–
7 mm long; plants drying pale to olive green or occasionally bronze ________________ S. biforme
4. Stems branched (or most individuals of a population with branched stems), with leaves/
bract-like leaves in addition to the paired bracts of the spathes.
7. Main stems usually more than 2 mm wide.
8. Lowest internode 10–30 cm long, often longer than the longest leaf; stems broadly
2-winged, with each wing as wide as central portion of stem and often 1 mm or
more wide; tepals pale blue to bluish violet, rarely white ____________________ S. angustifolium
8. Lowest internode 2.6–19 mm long, shorter than to equal to the longest leaf; stems
not broadly winged; tepals light bluish violet to purplish blue or blue.
9. Spathe bracts and/or stems, including peduncles, scabrous at least apically; hyaline
margins of inner spathe bract acuminate to acute apically ________________ S. pruinosum
9. Spathe bracts and stems glabrous; hyaline margins of inner spathe bract broadly
acute to obtuse or lobed apically _______________________________________ S. ensigerum
7. Main stems usually 2 mm or less wide.
10. Margins of outer spathe bract basally connate for 3.8–6.1 mm.
11. Ovaries blackish, in sharp contrast to the much lighter foliage; tepals light blue
to purplish blue, occasionally white; capsules 2–4 mm long ________________ S. atlanticum
11. Ovaries similar to foliage in color; tepals light blue; capsules 5–7 mm long
___________________________________________________________________ S. biforme
10. Margins of outer spathe bract basally connate for 2.2–3.8(–5) mm.
12. Plants very erect; stems 5–7 times as long as the peduncles (peduncles measured
from axil of subtending leaf to base of spathe); lowest internode 11–36
cm long, often longer than the leaves; ovaries blackish, in sharp contrast to much
lighter foliage; plants found in East TX only in extreme s part of Pineywoods
________________________________________________________________ S. atlanticum
12. Plants spreading to erect; stems ca. 4 times as long as the peduncles or less;
lowest internode 3.2–12.5 cm long, equaling or shorter than the leaves; ovaries
similar to foliage in color; plants widespread throughout East TX.
13. Spathe bracts and/or stems including peduncles scabrous at least apically,
the outer spathe bract 2.5–5.5 mm longer than inner, green; capsule tan to
light brown ___________________________________________________ S. pruinosum