Erythranthe marmorata

(Greene) G. L. Nesom

Phytoneuron 2012-39: 44. 2012.

Common names: Stanislaus or Whipple’s monkeyflower
EndemicConservation concern
Basionym: Mimulus marmoratus Greene Erythea 3: 73. 1895
Synonyms: M. whipplei A. L. Grant
Treatment appears in FNA Volume 17. Treatment on page 416. Mentioned on page 375.

Annuals, taprooted. Stems erect, simple or branched from base, 7–28 cm, usually moderately to densely villous-glandular, without eglandular hairs. Leaves usually cauline or basal persistent; petiole: proximals to medials 7–15 mm, distals 0 mm; blade palmately (3–)5-veined, ovate or broadly ovate to elliptic-ovate or depressed-ovate, (10–)15–30 × 6–15 mm, base truncate to shallowly cuneate, margins shallowly to coarsely dentate, apex acute, surfaces usually moderately to densely villous-glandular, without eglandular hairs. Flowers herkogamous, (1–)2–6, axillary from middle to distal nodes, chasmogamous. Fruiting pedicels 15–45 mm, usually moderately to densely villous-glandular, without eglandular hairs. Fruiting calyces sharply nodding, usually densely purple-spotted, broadly campanulate, inflated, sagittally compressed, 9–12 mm, densely hirtellous, sometimes sparsely stipitate-glandular, densely villous at sinuses, throat closing, adaxial lobe ca. 2 times length of others. Corollas yellow, throat red-spotted, abaxial limb base with a large red splotch, bilaterally symmetric, bilabiate; tube-throat narrowly cylindric-funnelform, 10–12 mm, exserted 4–5 mm beyond calyx margin; limb abruptly expanded 14–20 mm. Styles glabrous or sparsely hirtellous. Anthers included, glabrous. Capsules included, 6–9 mm.


Phenology: Flowering Mar–May.
Habitat: Habitat unknown, not over serpentine.
Elevation: 100–900 m.

Discussion

Erythranthe marmorata is recognized by its erect, taprooted habit and annual duration, villous-glandular vestiture, ovate-petiolate leaves, flowers from middle to distal nodes, long, narrow corolla tube-throat abruptly flaring into a broad limb, abaxial middle corolla lobe with a large red splotch, and fruiting calyces dark-spotted and sharply nodding. The species is known from foothills in Calaveras, Stanislaus, and Tuolumne counties in the Stanislaus River drainage and from Amador County in the Mokelumne River drainage. A collection from Fresno County appears to be somewhat disjunct from the main range, and the plants are more densely villous than characteristic elsewhere, but their identification as E. marmorata otherwise seems secure.

Erythranthe marmorata (previously identified as Mimulus whipplei) had been considered extremely rare or even perhaps extinct. See G. L. Nesom (2013d) for citations of recent collections.

Selected References

None.

Lower Taxa

None.