Vinca erecta Regel & Schmalhausen Apocynaceae

Abstract

Perennial; rootstock ligneous, horizontal, covered with scales; roots firm, stringy; stems erect, simple, two to many from common rootstock, 30–40 cm long; leaves elliptic or ovate to suborbicular, 4–5 cm long, 2–2.5 cm broad, narrowed at both ends, acute, glabrous, or densely covered on the margin and on the whole surface with very short hairs (var. hirsuta B. Fedtsch.), sessile, with several prominent longitudinal veins; Lowers solitary in leaf axils; pedicels 3–5 cm long, shorter than leaves, glabrous or densely hairy (var. hirsuta), contorted in fruit; flowers large, pale azure, or white within, rose outside, the tube violet; calyx segments 7.5–10 mm long, half or more than half the length of tube, linear-lanceolate, ciliate or rather densely hairy; with thick oblong teeth at base; corolla tube 15–20 mm long, narrow, abruptly enlarged about the middle, densely hairy within the upper part; corolla lobes elliptic, obovate or oblong, acute to obtuse, glabrous or the margin short ciliate at apex; stamens inserted at the middle of tube; anthers oblong, broad, half as long as the dilated part of filament; filaments inflexed, gradually narrowed towards base, geniculate at point of insertion; connective galeiform, dorsally white-bearded at apex; follicles 3–5 cm long, 0.6–0.7 cm broad, oblong, short-acuminate, terminating in a point recurved toward dorsal suture, longitudinally striped, glabrous or densely hairy (var. hirsuta); seeds few, 1–3 per follicle, cylindric, 12–13 mm long, brown to cinnamon colored, densely and coarsely tuberculate, the longitudinal furrow enlarged at base. Flowering March–April and fruiting May–June. Middle Asia, on serozems, fine-grained and coarse-skeletal soils, less often on stony-rubble, sandy slopes, from the plains to the mid-mountain belt, sometimes in Juniperus thickets. Uncommon, found in small populations (Shishkin and Boborov 1952) (Figs. 1, 2, and 3).