Neominois ridingsii
Ridings' Satyr

Family Description:
Alternate Common Name: Grasshopper Satyr.
Caterpillar: The caterpillar is reddish to light brown and marked lengthwise with white, greenish and brownish stripes. The body has tiny bumps and short white hairs.
Adult: The butterfly has a wingspan of 1 to 2 inches. It is grayish to light brown on the upperside, marked with large, oblong-shaped spots of off-white to very light brown on the outer halves of both the fore- and hindwings. The forewing is marked with one to three blackish eyespots with tiny white centers; the hindwing may also be marked with a small eyespot or black dot. Underneath is grayish to very light brown and appears speckled and marbled. The eyespots from above show through on the underside.

This species ranges from southern Alberta and Saskatchewan and southwestern Manitoba south through the Rockies and western Plains of the U.S. to central New Mexico and Arizona, and west into Nevada and central California. In Idaho, it has been documented to occur in Owyhee, Lemhi, and Custer counties.

It occurs in open, dry areas such as prairies, grasslands, and sagebrush steppe.


Caterpillar: Caterpillars feed on the leaves of blue grama grass (Bouteloua gracilis).
Adult: Butterflies feed rarely; the food of choice is flower nectar, primarily from yellow flowers in the sunflower family (Asteraceae).

There is usually only one new generation of caterpillars each year. Third and fourth instar caterpillars may overwinter in a physiological state called diapause. In a small portion of its range in California (Tuolumne County), the species is biennial. There, adults are only seen in even-numbered years because the caterpillars overwinter twice, the first winter as young caterpillars and the second after having molted several times. Pupation occurs in the spring. Adults generally fly from late May to early August. They hide in vegetation and exhibit an erratic flight when flushed.

Males perch to wait for receptive females. Females lay white eggs singly on the host grass and other plants.

Idaho Status: Unprotected nongame species.
Global Rank: G5
populations are widespread, abundant, and secure.

Ferris, C. D. and F. M. Brown. (eds.) 1981. Butterflies of the Rocky Mountain States. Univ. of Oklahoma Press, Norman, Oklahoma, USA, 442 pp.

Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. (Version 05Nov98).

Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies.  Second Edition.  Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.

Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.

Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.

Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.