The Eveningstar family are herbs or shrubs, which in all our species are rough or bristly with rough, barbed, sometimes stinging hairs. The leaves are mostly alternate, sometimes opposite, without stipules. The flowers are either solitary or arranged in open to condensed clusters. They are regular, with its parts attached on a disk surrounding the ovary, or growing on top of the ovary. The calyx is joined to the ovary in all our species, the free portion with a short to rather well-developed (often flared) extended flower axis, with usually 5 lobes which are persistent. There are usually 5, rarely 4 petals, which are separated in all our species. The stamens are usually numerous, separated or at the base joined into groups, some of them often expanded and forming petal-like sterile stamens alternating with the true petals. The anthers are mostly 2-celled. The ovary is situated underneath. The single style is mostly simple. The fruit is a capsule. The family has about 15 genera and 250 species worldwide, mainly in the New World, most abundant in tropical and partly -desert areas, especially in S. America.
Guide to Identify Presented Species of the Eveningstar Family
PETALS APPARENTLY 10
Mentzelia decapetala Ten-petal Eveningstar Perennial, 30-100 cm tall, rough with barbed, spine-like hairs. Dry, open slopes.
Flowers yellow-white, 8-12 cm across, with 10 petals, open in the evening.
Leaves alternate, fleshy, lanceolate, 4-15 cm long, pinnatifid with wavy lobes.
Mentzelia laevicaulis Smooth-stemmed Eveningstar Biennial, 30-100 cm tall, branched, with short, barbed hairs. Dry, open sites.
Flowers lemon-yellow, 5-15 cm across, with 5 petals, open at daytime.
Leaves alternate, oblanceolate, 4-15 cm long, pinnatifid with wavy lobes.
Alphabetical listing with links to presented species of the Eveningstar family: