Ceanothus bolensis
Ceanothus bolensis is a species of shrub in the buckthorn family commonly known as the Cerro Bola ceanothus. It is a rare member of the genus Ceanothus endemic to mountains with metavolcanic soils in extreme northwestern Baja California, Mexico. It is named after the Cerro Bola, a basaltic peak where the species is especially common and was first described from.
Description
Ceanothus bolensis is a shrub growing approximately in height and lacking a basal burl. It has small leaves measuring long by wide with a broadly obovate to oblanceolate shape, and deeply concave. The margins of the leaves are sharply dentate towards their distal ends, with 2 to 3 pairs of teeth and a tooth at the apex. The underside of the leaf has a prominent midvein. The leaves are smooth and lack hair and are colored a yellowish-green with a thick, leathery texture. The leaves are evergreen, and are arranged oppositely, and often grow clustered on short spur branches emerging from the axils. The inflorescence is a sub-umbellate axillary raceme. The flowers are pale blue and fade to a cream white in age. The fruits are globose and lack horns.C. bolensis is superficially similar to Ceanothus perplexans with its lack of fruiting horns and deeply concave, toothed leaves, but has much smaller, glabrous leaves. The smaller leaves are characteristic of Ceanothus ophiochilus, from which it also differs with a markedly different broadly obovate or broadly oblanceolate leaf shape. Ceanothus otayensis is another narrowly endemic species in the same region that can be distinguished from C. bolensis by its leaves that lack concavity, are hairy, and have revolute margins.