Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Rhynchospora, Key C: beaksedges with plumose bristles [subgenus Diplostylae; section Plumosae]

Cyperaceae

Rhynchospora

Copy permalink to share | Check for keys that lead to this key

1 Spikelets borne singly or a few together in loose clusters, some or all spikelets on slender stalks; achene 1.7-2.6 mm long, 1.2-2.0 mm wide.
  2 Achene obovoid, 1.7-2.0 mm long, 1.2-1.5 mm wide, the tubercle seated on its summit without a constriction or basal flange; longer bristles < ½ as long as the achene
  2 Achene broadly elliptic, 1.9-2.6 mm long, 1.5-2.0 mm wide, its summit constricted below a collar-like flange at the base of the tubercle; longer bristles three-fourths to exceeding the length of the achene
1 Spikelets borne several to many in clusters, none of the spikelets on slender stalks; achene 1.3-2.2 mm long, 0.9-1.7 mm wide
    3 Leaves (1-) 2-4 mm wide, slightly involute (V-shaped in ×-section) near the base; achene 1.8-2.2 mm long; [FL only].
      4 Spikelets 8-10 mm long; fertile scales 5-8 mm long; perianth bristles 5-8 mm long
      4 Spikelets 3.5-6 mm long; fertile scales 3-3.5 (-4) mm long; perianth bristles extending to about the tubercle apex
    3 Leaves 0.3-1.5 mm wide, strongly involute (and often appearing superficially terete) throughout their length; achene 1.3-2.1 mm long; [collectively more widespread].
        5 Basal sheaths shiny, dark brown; bristles longer than the tubercle; bristles plumose in a basal zone that extends 4-20% of the length of the bristle, then with a smooth zone, the terminal zone minutely denticulate; [Gulf Coastal Plain of FL, AL, and MS]
        5 Basal sheaths dull, light to medium brown; bristles shorter than the tubercle; bristles plumose in a basal zone that extends 40-90% of the length of the bristle, the terminal zone minutely denticulate (lacking a smooth middle zone); [widespread in the Atlantic and Gulf Coastal Plain from NC south to FL, west to TX]