16. Veronica L. (speedwell)
Plants annual or
perennial herbs, terrestrial or emergent aquatics. Stems variously erect to
prostrate, unbranched or branched, glabrous or hairy, the hairs sometimes
glandular. Leaves opposite (the leaflike inflorescence bracts usually
alternate), sessile or short-petiolate. Leaf blades simple, unlobed or
shallowly to moderately palmately 3- or 5-lobed, variously shaped, the margins
otherwise entire to scalloped or toothed, the surfaces glabrous or hairy, the
venation palmate or pinnate, but the lateral veins then sometimes very faint.
Inflorescences terminal or axillary racemes, sometimes appearing spikelike, the
flowers alternate along the axis (the lowermost sometimes subopposite), short-
to long-stalked; each subtended by a leaflike or reduced bract, but bractlets
absent. Flowers perfect. Calyces deeply 4- or less commonly 5-lobed nearly to
the base, actinomorphic or only slightly zygomorphic (the lower pair of lobes
then slightly longer than the upper pair), the lobes variously shaped, glabrous
or hairy. Corollas not bilabiate, weakly zygomorphic (the upper lobe larger and
the lower lobe smaller than the lateral lobes), moderately to relatively deeply
4-lobed, usually glabrous, the lobes spreading to loosely ascending, blue,
purple, pink, or white, often with darker veins, lacking a spur, the throat
open, sometimes abruptly much lighter than the lobes. Stamens 2, the filaments
relatively attached at the tip of the tube and exserted from the corolla, the
anther sacs more or less parallel; staminodes absent. Style 1, unbranched, the
stigma small, capitate, unlobed or shallowly 2-lobed. Fruits capsules,
heart-shaped to nearly circular or rarely broadly ovate in outline, slightly to
strongly notched at the tip, moderately to strongly flattened, glabrous or
hairy, the 2 locules equal in size, dehiscent longitudinally mostly along the 2
sutures (along the rim) and sometimes also along the locule wall (then
splitting into 4 more or less equal valves). Seeds 2 to numerous, oblong to
oblong-elliptic or oblong-ovate in outline (nearly circular in V.
heterophylla), flattened or concave on 1 side, flattened to convex on the
other side, the surface pale brown to yellowish brown, brown, or nearly black,
smooth, pebbled with a network of minute ridges, or with few to several coarse
cross-wrinkles. About 450 species, nearly worldwide.
Veronica has been considered a taxonomically
difficult genus with a large number of infrageneric groups containing
relatively cryptic species, these sometimes involving polyploid complexes. Even
the taxonomic limits of the genus have remained controversial (Albach et al.,
2004). Most of the Missouri species are Old World natives that either have
escaped from cultivation or are weedy taxa that were introduced to the New
World long ago. A number of species in the genus are popular in horticulture,
thus new escapes are likely to be recorded in the future. Interestingly, six of
the fourteen species found in the state were first reported since 1980 and a
seventh state record is reported for the first time in the present work, thus
the number of species documented for the state has doubled in the past few
decades.