Conicosia is a small genus of succulent perennial plants in the ice plant family (Aizoaceae), placed in the order Caryophyllales. The genus was formally described by N. E. Brown in 1925, in the journal Gardeners' Chronicle. Only two species are currently accepted — Conicosia elongata and Conicosia pugioniformis — both native to the Cape Provinces of South Africa, where they grow as relatively short-lived perennials arising from underground stems.
Members of the genus are known commonly as narrow-leaved ice plants, a name referring to their tentacle-shaped, dull-pointed, triangular leaves. They produce conspicuous, large tubular flowers that can exceed 10 centimeters across, each bearing up to 250 narrow, fringelike petals arranged in a ring around a center packed with hundreds of stamens. After flowering, the plant sets a capsule-type fruit that stays closed in dry conditions and opens only once wetted, gradually releasing hundreds of tiny seeds as the fruit's flesh dries and shrinks.
Conicosia pugioniformis, the better-documented of the two species, has also become naturalized outside its native range along the central coast of California, notably in Santa Barbara and San Luis Obispo counties, growing on dunes, beaches, coastal scrub, and grassland. Unlike some other invasive ice plants, it does not form dense mats, so its ecological footprint is comparatively limited; even so, it can become locally abundant and outcompete native vegetation, particularly in dune habitats. It spreads by seed and can resprout from buried root crowns after top growth is removed, and it carries a "Limited" invasiveness rating from the California Invasive Plant Council.
Distribution
Native to the Cape Provinces of South Africa. Conicosia pugioniformis has additionally naturalized along the central coast of California, particularly in Santa Barbara and San Luis Obispo counties, on dunes, beaches, coastal scrub, and grassland.
Ecology
Fruit capsules are hygrochastic, staying closed in dry weather and opening to release seed only when wetted. In its naturalized California range, C. pugioniformis does not form the dense mats typical of other invasive ice plants (e.g. Carpobrotus), so its impact is generally less severe, though it can locally crowd out native plants in dune habitats. It reproduces by seed and can resprout from buried root crowns; Cal-IPC rates it "Limited" for invasiveness.
