San Diego wirelettuce
Stephanomeria diegensis Gottlieb
Stephanomeria diegensis, known as San Diego wirelettuce, is an annual herb in the Asteraceae family. It is native to coastal regions of southern California, Baja California, and parts of Mexico. This species is notable for its hybrid origin from S. exigua and S. virgata, and is considered a product of homoploid hybrid speciation. The plant can grow over two meters tall with a branching, twig-like structure. It produces clusters of flower heads with white or pink-tinged ligules and has grooved, smooth or tuberculate achenes with plumelike pappus bristles. It is often misidentified as one of its parent species.
Description
Stephanomeria diegensis is an annual plant reaching 50-200 cm in height, with a single, glabrous stem that is either unbranched or has ascending to spreading branches. Basal leaves are linear to oblanceolate, runcinate, 3-10 cm long, and withered by flowering. The cauline leaves are much reduced and bract-like. The inflorescence consists of solitary or clustered heads on 3-4 mm peduncles, with involucres 7-9 mm long. The heads contain 11-13 florets. The cypselae are light tan to brown, 1.9-2.3 mm long, with smooth, slightly bumpy, or tuberculate surfaces and grooves. Pappi consist of 19-21 white bristles, plumose on the distal 80-85%. Chromosome number is 2n = 16.
Other common names
San Diego wirelettuce
Distribution
Guadalupe I. · California · Baja California · Mexico Northwest
