16. Section Lupulinae J.Carey

(Reznicek and Ball, 1974; Jones and Hatch, 1990)

Plants monoecious, with rhizomes absent or long-creeping, forming dense clumps or loosely spaced tufts, the sheaths of previous season’s basal leaves persisting and noticeable. Vegetative stems sometimes present and well developed, with several leaves. Flowering stems erect or ascending, sharply trigonous, glabrous, usually shorter than the leaves. Leaves basal and along the stems, all with well-developed leaf blades, glabrous. Leaf blades ascending or somewhat arching, the margins minutely roughened or toothed near the tip, flat or somewhat corrugated in cross-section. Leaf sheaths with the ventral side thin and white, sometimes breaking apart at maturity. Inflorescences short to somewhat elongate, with the terminal spike staminate (rarely with a second, staminate spike) and 1–5 lateral, pistillate spikes. Staminate spikes linear in outline. Pistillate spikes sessile or short-stalked (less commonly long-stalked in C. lupulina), with 1–80 perigynia, the bracts leaflike, the lowermost bracts longer than the inflorescence, with well-developed sheaths or the uppermost with the sheath lacking or very short. Perigynia 10–20 mm long, ascending or spreading in all directions, inflated, circular to obscurely trigonous in cross-section, tapered to a conical beak with 2 narrow, stiff, spreading to ascending teeth 0.5–2.0 mm long at the tip, the base angled or rounded, the surface with 13–25 strong nerves, glabrous (sometimes hairy in C. grayi). Styles persistent, straight or contorted (abruptly bent, curved, or looped) in the lower half, not jointed to the main body of the fruit, which is long-beaked at maturity. Stigmas 3. Fruits strongly trigonous in cross-section with convex to concave sides, the angles sometimes thickened, yellowish white to brown. Six species, eastern U.S., Canada.

The inflated perigynia of species in this section are the longest of the Missouri sedges.