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Merced phacelia
Phacelia ciliata var. opaca


None federal or state. California Native Plant Society List 1B.

Life History

This annual plant flowers between February and May. Merced phacelia is restricted to heavy clay soils on the San Joaquin Valley floor and adjacent low hills at elevations below 100 m. Other aspects of its life history and habitat have not been reported.

The leaves of Merced phacelia vary in both size and shape, ranging from 3 to 15 cm long and from deeply-lobed to divided. Each branch tip is coiled like a scorpion's tail and holds many flowers. The individual flowers are five-petaled, bell-shaped, and blue with pale centers. The calyx has five ciliate (i.e., with stiff hairs along the margin) lobes but is inconspicuous while the flowers are open. As the fruits mature, the calyx lobes elongate and become opaque. Each spherical fruit contains four seeds.


Merced phacelia was collected in east-central Merced County near the towns of Le Grand, Merced, Planada, and Tuttle between 1929 and 1939. A very small population, consisting of fewer than 10 individuals, was observed in 1977 approximately 10 km northeast of Merced. The other historical locations have not been visited for over 50 years due to a lack of access. However, Merced phacelia is assumed to remain extant at the historical sites because these areas have not been developed or converted to agriculture.


Subclass ASTERIDAE, Order SOLANALES, Family HYDROPHYLLACEAE, Genus Phacelia, Species ciliata


Merced phacelia is one of two varieties of Phacelia ciliata. The other is variety ciliata, commonly known as Chinese-lantern phacelia.

Recent Synonyms


Other Common Names



Skinner, M.W., and B.M. Pavlik, eds. 1994. Inventory of rare and endangered vascular plants of California. Fifth edition. Spec. Publ. No. 1, California Native Plant Society, Sacramento, 338 pp.; Wilken, D.H., R.R. Halse, and R.W. Patterson. 1993. Phacelia. Pp. 691-706 in The Jepson manual: higher plants of California (J.C. Hickman, ed.). University of California Press, Berkeley, 1400 pp.; Howell, J.T. 1936. Two new Californian plants. Leaflets of Western Botany 1:221-222; Rarefind, California Natural Diversity Data Base, Sacramento.


10-55 cm
8-10 mm
4-5 mm in diameter
2.5-3.5 mm long


In Chinese-lantern phacelia the calyx lobes grow broader and remain translucent at maturity.

Authors of Profile

E.A. Cypher

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