6. Phacelia ranunculacea (Nutt.) Constance
Pl. 429 a, b;
Map 1921
Plants
relatively slender annuals. Stems 7–25 cm long, unbranched or more commonly
few- to several-branched at the base and above, loosely to strongly ascending
from a sometimes spreading base, moderately pubescent with stiff, loosely
ascending to spreading, nonglandular hairs toward the base, these grading into
dense, fine, gland-tipped hairs well below the midpoint (median portion with
sparse to moderate nonglandular hairs and moderate to dense glandular hairs).
Basal (and lower stem) leaves often persistent at flowering, the blade 1–3 cm
long, broadly ovate to broadly elliptic or oblong-elliptic in outline,
pinnately compound with 3–7 pinnae, these unlobed or (especially the terminal
pinna) mostly moderately to deeply 2- or 3-lobed and sometimes also with a few
additional teeth or smaller lobes, the teeth or lobes sharply to bluntly
pointed or occasionally rounded at the tips, the surfaces sparsely to
moderately pubescent with more or less appressed, stiff hairs. Stem leaves all
moderately to long-petiolate, the blade 1–4 cm long, progressively less divided
toward the stem tip, the uppermost leaf blades often irregularly 3-lobed, the
leaflets or lobes sharply to bluntly pointed or occasionally rounded at the
tips, the terminal lobe of at least the uppermost leaf (immediately below the
lowermost flower) narrowly angled or tapered at the base, the pubescence
similar to that of the basal leaves (but the petiole often with at least some
glandular hairs). Inflorescences with only 2–6 flowers, the axis and flower
stalks densely pubescent with gland-tipped hairs, rarely also with a few
nonglandular hairs, the stalks spreading to downward-arched or pendant at
fruiting. Calyces 3–7 mm long, the lobes with the margins and surfaces
pubescent with mostly nonglandular hairs (glandular hairs more frequent toward
the calyx base). Corollas 2–4(–5) mm long, narrowly bell-shaped to nearly
cylindrical, white or pale lavender to bluish-tinged, the margins entire, the
outer surface glabrous. Stamens not exserted, the filaments 1.5–2.0 mm long,
glabrous. Ovary with 4 ovules. Style branched to about the midpoint. Fruits 4–6
mm long, the surface usually irregularly swollen (distended by the seeds),
2–4-seeded. Seeds 1.8–2.5 mm long, broadly ovoid-angled to nearly globose,
finely ridged, light brown to brown. 2n=12. April–May.
Uncommon in the
Mississippi Lowlands Division west locally to Oregon County (Indiana to
Tennessee and Mississippi west to Illinois, Missouri and Arkansas). Bottomland
forests, mesic upland forests in ravines, and bases and ledges of bluffs; also
gardens and shaded disturbed areas.
As noted above
in the discussion of Nemophila, Palmer and Steyermark (1935)
misdetermined the initial collections of this species in Missouri as a member
of that genus. During his systematic studies of Nemophila, Constance
(1949a, b) redetermined the Missouri specimens as Phacelia ranunculacea
and Steyermark (1963) subsequently included the species in the state’s flora
under that name. For a discussion of the segregation of P. covillei from
P. ranunculacea, see the treatment of that species.