Rockloving Wavewing

Pteryxia petraea (M. EJones) Coult. & Rose, Contr. U. S Nat. Herb. 7: 172. 1900.
Cymoplerus pelraeus M. E. Jones, Contr. W. Bot. 8: 32. 1898.
Plants caulescent, 15-45 cm. high; leaves narrowly oblong in general outline, excluding the petioles 3.5-17 cm. long, 0.5-5 cm. broad, ternate-bipinnate to tripinnate, the ultimate divisions linear, acute, 1-8 mm. long, 0.5-1 mm. broad, distinct; petioles 5-12 cm. long; peduncles slender, 9-25 cm. long; involucel dimidiate, the bractlets linear, 1-3 mm. long; rays 3-7, very unequal, 1-55 mm. long, the inner shortened or obsolete; pedicels 1-6 mm. long; flowers yellow; fruit ovoid to ovoid-oblong, 4.5-7 mm. long, 2-4 mm. broad, the wings plane, narrower than or equaling the body, 1-3 of the dorsal ribs winged, these dorsal wings equaling or shorter than the lateral wings; oil-tubes 1-3 (usually 3) in the intervals, 5-15 on the commissure; accessory oil-tubes usually wanting; strengthening cells inconspicuous.
Type locality: Palisade, Nevada, M. E. Jones.
Distribution: Southern Idaho and central Nevada to southeastern Oregon, eastern California, and northern Arizona (Cusick 1995, Macbride & Pay son 3053).