Mimulus suksdorfii Gray 



Suksdorf monkey-flower 



A. DESCRIPTION 



1. General description: This is an inconspicuous member of 

 the Scrophulariaceae (figwort family). These small taprooted 

 annuals are branched or often unbranched in Montana. The 

 flowers are borne two per node in the axils of the opposite 

 leaves, which are narrow, entire margined, and without 

 petioles. The green (with a reddish tinge) calyx is fused 

 with a 5 angled tube and 5 short pointed lobes. The yellow 

 corolla is tubular with 5 nearly equal lobes. There are 4 

 stamens and a single pistil with 2 stigmas. The tiny seeds 

 are borne in a capsule which splits longitudinally. Slide 12 

 in Appendix E is a close-up of M. suksdorfii . 



2. Diagnostic characters: Separated from other annual species 

 of Mimulus by its narrow leaves and short (4-8 mm) yellow 

 corolla. Resembles Collinsia parviflora , which occurs in 

 similar habitat but has blue corollas. 



B. GEOGRAPHICAL DISTRIBUTION 



1. Species range: Southern Washington, eastern Oregon and 

 California, east across Idaho, Nevada, and Utah, to western 

 Wyoming, northern Colorado, and northern Arizona (Cronquist et 

 al. 1984), and Montana (Dorn 1984). 



2. Montana distribution: Previously known from 8 sites in 

 Beaverhead, Carbon, Glacier, and Missoula/Ravallii counties. 



3. Occurrences in the study area: Ten populations are known 

 from the area, eight discovered by this project. These are 

 distributed in the canyons throughout the range. 



C. HABITAT 



This species is common (almost predictable) in patches of 

 surface accumulations of mineral soil and organic litter on 

 limestone talus and in shrub communities. It is known from 

 the Tendoys at elevations ranging from 6,300 to 7,500 ft 

 (1,919-2,284 m) . Common woody associates include Artemisia 

 tridentata and Cercocarpus ledifolius . Agropyron spicatum, A. 

 swithii, and Leucopoa kingii are dominant grasses in these 

 habitats. Although these are generally dry environments, at 

 least ephemeral surface moisture is necessary, since these are 

 annuals with shallow root systems. The extremely wet 1993 

 growing season may have been partially responsible for the 

 many populations which were found. At a few sites another, 

 small, annual, but less common MPSSC, Phacelia incana , grows 

 intermixed with M. suksdorfii . Outside of the study area, the 

 species is reported from moist areas beside water. 



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