Carex sect. Granulares

(O. Lang) Mackenzie in N. L. Britton et al.

in N. L. Britton et al., N. Amer. Fl. 18: 260. 1935.

Basionym: Granulares O. Lang Linnaea 24: 582. 1851
Treatment appears in FNA Volume 23.
Revision as of 20:11, 16 December 2019 by FNA>Volume Importer

Plants cespitose or not, short to long rhizomatous, sometimes inconspicuously rhizomatous. Culms sometimes solitary, brown at base. Leaves: basal sheaths not fibrous; sheath fronts membranous; blades M-shaped in cross section when young, adaxial side of blade with 2 lateral veins more prominent than midvein, widest leaves not more than 10 mm wide, glabrous. Inflorescences racemose, with (2–)3–6 spikes; proximal nonbasal bracts leaflike, long-sheathing, sheath more than 4 mm, longer than diameter of stem; lateral spikes pistillate or androgynous, rarely distal 1–3 spikes staminate, sometimes some basal, pedunculate, prophyllate; terminal spike staminate. Proximal pistillate scales with apex acute, acuminate, or short-awned. Perigynia ascending to spreading, minute red-brown or yellowish streaks and dots, distinctly veined, sessile, ellipsoid or rhomboid to broadly ovoid, obovoid, or subglobose, obscurely trigonous to round in cross section, base rounded, apex rounded, abruptly beaked, glabrous; beak 0.1–0.9 mm, orifice entire to minutely bidentulate, teeth 0–0.3 mm. Stigmas 3. Achenes trigonous, smaller than bodies of perigynia; style deciduous.

Distribution

Temperate and subtropical regions of North America, s Mexico, Central America (Guatemala).

Discussion

Species 6 (4 in the flora).

Carex sect. Granulares is a monophyletic section diagnosed by at least three apormorphies: red-brown or yellowish cells scattered in the epidermis of the perigynia, often 25 or more perigynia per well-developed lateral spike, and perigynia loosely enveloping the achenes (R. F. C. Naczi 1992, 1997). Recent phylogenetic analyses indicate section Granulares is the sister group of a clade composed of sections Careyanae and Griseae (R. F. C. Naczi 1992).

Selected References

None.

Key

1 Plants with short or inconspicuous rhizomes; culms in tufts; terminal spike and distal lateral spike usually overlapping; proximal spikes usually arising from distal 1/2 of culms. > 2
1 Plants with long-creeping rhizomes; culms mostly solitary; terminal spike and distal lateral spike (unless staminate) usually separated; proximal spikes usually arising from proximal 1/2 of culms. > 3
2 Leaves green, not glaucous; longest bract blade (per plant) of distal lateral spike 1.6–4.6(–7.1) cm; ligule of proximal bract 0.5–6.5 mm; perigynia (1.6–)1.9–3 times as long as thick. Carex gholsonii
2 Leaves not green, usually glaucous; longest bract blade (per plant) of distal lateral spike 4.1–15.8 cm; ligule of proximal bract (2–)3–17.5(–26) mm; perigynia 1.4–2.2(–2.4) times as long as thick. Carex granularis
3 Staminate scales with apex acute to awned; widest leaves 2.8–8.3 mm wide; perigynium beak 0.3–0.9 mm. Carex microdonta
3 Staminate scales with apex rounded to obtuse; widest leaves 1.8–3(–4.4) mm wide; perigynium beak 0.1–0.3 mm. Carex crawei