5. Cuscuta cuspidata Engelm. (cusp dodder)
Pl. 364 e; Map
1587
Stems relatively
slender, usually less than 1 mm in diameter. Flowers 2.5–3.5 mm long, with
smooth to slightly irregular surfaces, subtended by 2–4 loosely overlapping,
ovate bracts with pointed, erect tips, in loose, paniculate clusters on short
side branches, the pedicels usually shorter than the flowers. Calyces 1/2 to
2/3 as long as the corolla tube, not hidden by the bracts, deeply 5-lobed into
separate or nearly distinct sepals, the sepals ovate to nearly orbicular, with
a bluntly pointed tip, strongly overlapping basally, but not angled. Corollas
narrowed to 5 sharply or rarely bluntly pointed lobes, these spreading to
reflexed, with straight tips. Infrastaminal scales not quite reaching filament
bases, narrowly oval, densely fringed along the margins. Fruits globose or
nearly so, thickened at the tip. Seeds 1.4–1.5 mm long. July–October.
Scattered in the
southern half of the state (Indiana and Louisiana west to Utah). Mostly on the
banks of rivers, streams, and ponds, but also in wet prairies; sometimes a weed
in fields. Parasitic on a wide variety of herbaceous species (including Ambrosia,
Aster, Erigeron, Impatiens, Iva, Lycopus, and Vernonia), mostly in
the Asteraceae.