12. Hypericum pseudomaculatum Bush ex Britton (spotted St. John’s wort)

H. punctatum Lam. var. pseudomaculatum (Bush ex Britton) Fernald

H. punctatum f. flavidum Steyerm.

Pl. 361 g, h; Map 1572

Plants perennial herbs, the rootstock and stem bases often somewhat woody, often with short to long rhizomes. Stems occurring singly or less commonly 2 or more together, 40–100 cm long, erect or ascending, rounded or bluntly and inconspicuously angled below, green to more commonly reddish brown and usually with noticeable yellowish brown or black dots, lines, and/or streaks, the surface rarely peeling in thin strips with age. Leaves not jointed at the base. Leaf blades 10–60 mm long, 4–20 mm wide, those of the uppermost leaves ovate to broadly triangular-ovate (those farther down the stem narrowly ovate to narrowly elliptic), mostly sharply pointed at the tip, rounded to shallowly cordate at the base, often somewhat clasping the stem, the margins flat or less commonly slightly rolled under, herbaceous in texture, with 1 or less commonly 3 main veins visible toward the base, the surfaces with usually many noticeable yellowish brown to dark green or black dots, the upper surface green, the undersurface paler but only rarely slightly glaucous. Inflorescences appearing as panicles of 20–200 flowers, rounded to more or less flat-topped in outline. Flowers actinomorphic. Sepals 5, all more or less similar in size and shape, 5–7 mm long, not becoming enlarged at fruiting, elliptic-lanceolate, the margins flat, with abundant noticeable black dots, lines, or streaks (additional inconspicuous yellowish brown to dark green dots, lines, or streaks may be present). Petals 5, 8–12 mm long, narrowly obovate, orangish yellow to bright yellow or less commonly lemon yellow or pale yellow, with abundant yellowish brown to black dots, lines, and/or streaks occurring irregularly across the entire surface, withered and inconspicuous but usually persistent at fruiting. Stamens 40–60, the filaments not fused into noticeable groups or occasionally fused inconspicuously into 3 or 5 groups toward the base. Ovary completely 3-locular (sometimes incompletely so at the very tip), the placentation axile. Styles 3, free above the base, more or less spreading, persistent, the stigmas capitate. Fruits 5–7 mm long, ovoid, widest below the midpoint, tapered to the minute beaks, bluntly triangular to more or less circular in cross-section, the surface usually with abundant yellowish brown dots and/or lines. Seeds numerous, 0.7–0.9 mm long, the surface with a fine network of ridges and pits, sometimes appearing inconspicuously longitudinally ribbed, light brown to brown. 2n=16. June–September.

Scattered in the Unglaciated Plains Division and all but the easternmost portion of the Ozarks (southeastern U.S. west to Oklahoma and Texas). Upland prairies, glades, ledges and tops of bluffs, dry upland forests, and savannas; also ditches and roadsides.

This species was originally described by Britton (1901) based upon B. F. Bush’s manuscript and his collections from the vicinity of Swan, in Taney County (Mackenzie and Bush, 1902). Steyermark (1963) followed Fernald (1935) in treating it as a variety of the closely related H. punctatum, citing the existence of intermediate specimens in the state. However, Culwell (1970), who studied the systematics of this complex, found very limited morphological overlap between H. pseudomaculatum and H. punctatum and further suggested that opportunities for hybridization between them were limited by apparent high rates of inbreeding in both taxa. Occasional Missouri specimens may have somewhat intermediate leaf shapes or flower sizes (possibly indicative of hybridization), but the vast majority of specimens can be determined reliably to one or the other species.