Arctomecon

Herbs, perennial, evergreen, cespitose, scapose or very short-caulescent and subscapose, from taproots. Stems (caudices) when present leafy, erect, branching, covered with marcescent leaf bases. Leaves all or mostly basal and rosulate, petiolate; blade cuneate to fan-shaped, 1×-lobed distally, glaucous, long-pilose, hairs flexuous, barbed; margins entire; lobes acute, long-bristled. Inflorescences terminal, cymiform, simple or branching; bracts present; buds nodding. Flowers: sepals 2 or 3, distinct; petals persistent, 4 or 6; stamens many; pistil 3-6-carpellate; ovary 1-locular; style 1 and short, or absent; stigmas 1 per carpel, connate, capitate, cordately 2-lobed. Capsules erect, 3-6-valved, dehiscing from apex leaving persistent placental ribs unseparated at apex, valve tips recurving. Seeds several to many, dark brown, shining, ovoid, 1.5-3 mm, aril present. x = 12.

Distribution

North America (Mojave Desert).

Discussion

Species 3 (3 in the flora).

Selected References

Janish, J. R. 1977. Nevada's vanishing bear-poppies. Mentzelia 3: 2-5.

Mozingo, H. N. and Margaret Williams. 1980. Threatened and Endangered Plants of Nevada: An Illustrated Manual. [Washington.]

Nelson, D. R. and K. T. Harper. 1991. Site characteristics and habitat requirements of the endangered dwarf bear-claw poppy (Arctomecon humilis Coville, Papaveraceae). Great Basin Naturalist 51: 167-175.

Nelson, D. R. and S. L. Welsh. 1993. Taxonomic revision of Arctomecon Torr. & Frem. Rhodora 95: 197-213.

Raynie, D. E., D. R. Nelson, and K. T. Harper. 1991. Alkaloidal relationships in the genus Arctomecon (Papaveraceae) and herbivory in A. humilis. Great Basin Naturalist 51: 397-403.

Welsh, S. L. and K. L. Thorne. 1979. Illustrated Manual of Proposed Endangered and Threatened Plants of Utah. [Washington.]

Lower Taxa

Arctomecon californica, Arctomecon humilis, Arctomecon merriamii

Key

1	Petals 4, 1.2–2.5 cm, marcescent; leaf blades minutely hirsute but only sparsely long-pilose.	Arctomecon humilis
1	Petals 6, 2.5–4 cm, caducous; leaf blades copiously long-pilose.	> 2
2	Inflorescences 1(–6)-flowered; flower buds long-pilose; petals white.	Arctomecon merriamii
2	Inflorescences 3–20-flowered; flower buds glabrous; petals deep yellow.	Arctomecon californica