Erythranthe inamoena

Annuals, fibrous-rooted, rooting at proximal nodes, sometimes forming matlike colonies. Stems decumbent to decumbent-ascending basally, becoming fully erect at least in inflorescence, simple, sometimes few-branched from proximal nodes, usually distinctly fistulose, 10–30 cm, glabrous. Leaves basal and cauline, basal sometimes deciduous by flowering; petiole: basal and proximals to mid cauline 10–70 mm, distals 0 mm; blade palmately veined, ovate to broadly ovate or elliptic-ovate, becoming subreniform distally, (5–)15–35(–60) mm, distal closely paired, auriculate-subclasping, base truncate to subcordate, margins dentate-serrate to shallowly dentate, teeth 5–11 per side, apex obtuse to rounded, surfaces glabrous. Flowers plesiogamous, (6–)8–18(–24), often produced from all nodes, loosely to densely racemose, chasmogamous. Fruiting pedicels 9–20 mm, glabrous, rarely sparsely stipitate-glandular. Fruiting calyces purple-spotted, sometimes greenish, broadly cylindric-campanulate, inflated, sagittally compressed, 7–11 mm, glabrous, rarely minutely scabrous-hirtellous or sparsely stipitate-glandular, throat not closing, abaxial lobe slightly upcurving 10–45º, spreading 45º, or sometimes deflexed 40º. Corollas yellow, red-spotted, bilaterally symmetric, bilabiate; tube-throat cylindric, 7–11 mm, exserted (1–)2–3(–4) mm beyond calyx margin; limb slightly expanded. Styles glabrous. Anthers included, glabrous. Capsules included, 4.5–6 mm. 2n = 60.

Phenology: Flowering Jan–Apr(–Sep).
Habitat: Edge of seeps and creeks, mud or gravel, shallow running water, wet crevices, canyon drainages.
Elevation: 100–2400 m.

Distribution

• Generated Map
• Legacy Map

Tex., Mexico (Chihuahua, Coahuila).

Discussion

Erythranthe inamoena is distinctive in its completely glabrous herbage, small corollas, flowers in racemes mostly at distal nodes and with reduced bracts, short and open-throated fruiting calyces, erect and fistulose stems, and apparent annual duration (fibrous-rooted but usually rooting at proximal cauline nodes).

Presumably because of its autogamous reproduction, Erythranthe inamoena has been confused with E. cordata, especially in the trans-Pecos region of Texas, where the two are sympatric. In contrast to E. cordata, E. inamoena usually has glabrous pedicels and calyces, flowers often produced from all nodes, smaller calyces [(7–)8–11 mm] that do not close at maturity, and corollas with a shorter tube-throat (7–11 mm).

Some populations in Brewster, Presidio, and Val Verde counties are identified here as Erythranthe inamoena (based on proximal-to-distal distribution of flowers and the short mature calyces with open throat) but have sparsely stipitate-glandular pedicels and calyces.

Selected References

None.

Lower Taxa

None.