19. Symphyotrichum puniceum (L.) Á. Löve & D. Löve (glossy-leaved aster)

Aster puniceus L.

A. firmus Nees

A. puniceus var. firmus (Nees) Torr. & A. Gray

A. puniceus ssp. firmus (Nees) A.G. Jones

S. firmum (Nees) G.L. Nesom

A. puniceus f. lucidulus (A. Gray) Fernald

A. lucidulus (A. Gray) Wiegand

Pl. 248 a, b; Map 1031

Plants perennial herbs, colonial from relatively long-creeping rhizomes. Stems 1 or less commonly few, 50–170 cm long, with few to more commonly several ascending to spreading branches above the midpoint, sparsely pubescent toward the tip with lines or bands of spreading, often stout and stiff (sandpapery) hairs (more densely and evenly hairy elsewhere), glabrous toward the base. Basal as well as lower to median stem leaves absent at flowering, sessile to short-petiolate, the blade 3–12 cm long, 0.5–3.0 cm wide, narrowly oblanceolate to oblanceolate, tapered at the base, rounded or angled to a bluntly or sharply pointed tip, the margins entire to sparsely toothed and relatively strongly roughened, the upper surface often somewhat shiny, glabrous or less commonly somewhat roughened with sparse, short, stout hairs, the undersurface sparsely roughened with short, stout hairs along the midvein, occasionally with a few softer hairs between the veins, the secondary veins on the leaf undersurface relatively easily observed, fused into an irregular network, the veinlets also forming a dense, irregular network of relatively short to somewhat elongate areoles. Median and upper stem leaves often relatively numerous, more or less progressively smaller toward the stem tip, sessile, usually strongly clasping the stem (the uppermost leaves sometimes somewhat sheathing), the blades 2–16 cm long, lanceolate to oblanceolate (often narrowly so), oblong-oblanceolate, or less commonly nearly elliptic, cordate to nearly truncate at the base, angled or tapered to a sharply pointed tip, the margins entire or shallowly toothed, otherwise similar to the lower stem leaves. Inflorescences usually appearing as open panicles, sometimes with solitary heads or small clusters at the tips of relatively long branches, the heads appearing mostly short-stalked, the bracts somewhat shorter than the adjacent foliage leaves, 0.5–1.5 cm long, narrowly lanceolate or oblanceolate to linear. Heads mostly 2–4 cm in diameter (including the extended ray corollas) at flowering. Involucre 6–12 mm long, the bracts in 4–6 subequal, overlapping series. Involucral bracts linear to narrowly oblong-oblanceolate, angled or tapered at the sharply pointed tip, the tip loosely ascending to somewhat spreading, those of the outer series more or less leaflike, the green portion extending more than 2/3 of the way to the somewhat thickened, pale base, those of the median and inner series with a progressively shorter, elliptic, green apical area (this mostly 1/2 the length or more), sometimes purplish-tinged along the margins toward the tip, the outer surface glabrous (the inner surface usually sparsely hairy toward the tip), the margins usually finely hairy, especially toward the base. Ray florets 25–45 in 1 or 2 series, the corollas well developed, 12–20 mm long, lavender to purple to bluish purple. Disc florets 30–70, the corollas 4.5–6.5 mm long, the slender portion of the tube shorter than the slightly expanded apical portion, the lobes 0.4–0.8 mm long, 20–30 percent of the total length of the expanded portion. Pappus bristles 4.5–7.0 mm long, off-white to pale cream-colored. Fruits 2.0–3.5 mm long, with 4 or 5 longitudinal ribs, purplish brown to brown, glabrous or sparsely hairy. 2n=16, 32. August–October.

Scattered mostly in the eastern half of the Ozark and Ozark Border Divisions with a disjunct population in Boone County (Minnesota, Nebraska, and Missouri east to West Virginia, North Carolina, and Georgia). Fens, calcareous seepage areas along streams, and bottomland prairies.

Steyermark (1963) considered S. puniceum (as Aster puniceus) in Missouri to represent a relict from Pleistocene glacial times confined to cool, moist microhabitats. He recorded rare putative hybrids between this species and S. lateriflorum from Dent and Shannon Counties. Jones (1989) mentioned intergradation in Illinois with other asters having as their base chromosome number, including S. lanceolatum and S. praealtum.

The taxonomy of the S. puniceum complex requires more study. On the one hand, some authors (A. G. Jones, 1980; Gleason and Cronquist, 1991; Warners and Laughlin, 1999) have recognized two species, S. puniceum and S. firmum (with a couple of additional morphological extremes sometimes segregated within S. puniceum as subspecies). On the other hand, some recent students of the group (Semple et al., 2002) have felt it unwise to provide any formal taxonomic recognition for the two main variants because of a perceived large number of morphological intermediates and widely overlapping ranges. Still other authors (Steyermark, 1963; Jones, 1989) have treated the main variants as varieties or subspecies of S. puniceum. This last option has merit, but the epithet firmus has not yet been formally transferred to Symphyotrichum at the varietal or subspecific level and is therefore not available for use. Thus far, the most detailed study of the complex was that of Warners and Laughlin (1999), who presented evidence that the two taxa do not intergrade for critical characters in a series of populations where they co-occur in Michigan. They characterized S. firmum as having a more strongly rhizomatous rootstock with less clustered stems that are less densely hairy and generally smaller basal leaves, among other characters. However, their observation that S. firmum has white to pale lavender ray corollas does not hold up in material from other states, where the ray corollas in both morphotypes usually are purple to bluish purple. In Missouri, as noted by Steyermark (1963), the populations occurring in calcareous seepage communities in the eastern Ozarks and adjacent counties correspond to S. firmum. Symphyotrichum puniceum in the strict sense is not yet known from Missouri, but it occurs in the adjacent portions of the Great Plains.