Erythranthe cordata

Annuals, fibrous-rooted, sometimes producing leafy runners from basal nodes, stems often rooting at proximal nodes and appearing rhizomelike. Stems usually erect, usually simple, usually fistulose, 12–40 (–100) cm, sparsely stipitate-glandular, hairs fine, gland-tipped. Leaves basal and cauline, basal persistent; petiole: basal and proximals 6–20 (–40) mm, midcauline to distals 0 mm; blade not connate, palmately 3–5 (–7) -veined, orbicular to broadly elliptic-ovate or oblongelliptic, cauline becoming broadly ovate to narrowly reniform, basal and mid cauline 15–30 (–50) mm, gradually reduced in size distally to 6 mm, basal largest, distal closely paired, auriculate-subclasping, base cuneate to truncate or shallowly cordate, margins shallowly, evenly to unevenly dentate, apex obtuse to rounded, surfaces glabrous. Flowers plesiogamous, (5–) 10–16, at distal nodes, in bracteate racemes, chasmogamous or cleistogamous. Fruiting pedicels 10–30 (–45) mm, longer than subtending leaves, minutely stipitate-glandular. Fruiting calyces nodding 45–90º, not red-dotted, broadly elliptic-ovoid, inflated, sagittally compressed, (8–) 14–18 (–20) mm, glabrous or sparsely stipitate-glandular to hirsutulous, sometimes mixed glandular-hirsutulous, throat closing, adaxial lobe not distinctly longer than abaxial, not falcate. Corollas yellow, red-spotted, abaxial limb deeper yellow, weakly bilaterally or radially symmetric, weakly bilabiate or regular; tube-throat sometimes tubular and not opening (cleistogamous), 8–14 mm, exserted 1–3 mm beyond calyx margin; limb not expanded or expanded 9–14 mm. Styles glabrous. Anthers included, glabrous. Capsules included, stipitate, 5–7 mm. 2n = 60.

Phenology: Flowering (Jan–)Mar–Jun(–Nov).
Habitat: Springs, seeps, stream edges, muddy banks, flood plains, marshes and swamps, wash bottoms, wet depressions, wet places among boulders.
Elevation: (600–)800–2400(–3000) m.

Ariz., Calif., Colo., Nev., N.Mex., Tex., Utah.

Discussion

Erythranthe cordata is characterized by its fibrous-rooted habit (annual in duration, without rhizomes but commonly rooting at the proximal nodes), short corollas and autogamous reproduction (anthers and stigma at the same level), closed calyces, sparsely villous-glandular vestiture (lacking hirtellous, eglandular hairs), and stems commonly fistulose in larger plants. The short corollas and other features of autogamous reproduction of E. cordata are diagnostic and prominent. Plants of E. cordata are highly variable in size, from tiny fibrous-rooted plants with nearly filiform stems to much larger individuals with fistulose stems rooting at proximal nodes.

Erythranthe cordata and E. nasuta are sympatric in Arizona, southeastern New Mexico, and southern Utah, and small plants of each species may be similar in aspect, both with cleistogamous flowers and reduced vestiture. Erythranthe nasuta can be recognized by its distal and bracteal leaves with hirtellous to hirsutulous adaxial surfaces; a 10/x lens usually is required to see this feature, and it sometimes is most obvious around the leaf margins.

The common name of Erythranthe cordata alludes to a fancied resemblance of the corollas to the horn of a diminutive trumpet.

Selected References

None.

Lower Taxa