Euphorbia golondrina

L. C. Wheeler

Proc. Biol. Soc. Wash. 53: 8. 1940.

Common names: Canyon or swallow spurge Boquillas sandmat
Conservation concern
Synonyms: Chamaesyce golondrina (L. C. Wheeler) Shinners
Treatment appears in FNA Volume 12. Treatment on page 269. Mentioned on page 258, 270.

Herbs, annual, with slender taproot. Stems prostrate, 5–35 cm, glabrous. Leaves opposite; stipules distinct, subulate, 0.5–0.8 mm, glabrous; petiole 0.8–1 mm, glabrous; blade oblong, ovate-oblong, to narrowly elliptic-oblong, 5–11.5 × 1–4 mm, base asymmetric, cuneate to rounded, margins entire, thickened and often revolute on drying, apex obtuse, surfaces glabrous; only midvein conspicuous. Cyathia solitary at distal nodes; peduncle 0.9–1.5 mm. Involucre turbinate, 0.9–1.5 × 0.8–1.3 mm, glabrous; glands 4, occasionally rudimentary, red to purple, deeply concave, subcircular, 0.3–0.4 × 0.3–0.4 mm; appendages white, semilunate to slightly flabellate, 0.1–0.3 × 0.5–0.8 mm, distal margin entire. Staminate flowers 28–40. Pistillate flowers: ovary glabrous; styles 0.3–0.4 mm, 2-fid nearly entire length. Capsules broadly ovoid, 1.7–2 × 1.5–1.6 mm, glabrous; columella 1.4–1.7 mm. Seeds narrowly pyramidal-ovoid, 4-angled in cross section, 1.3–1.5 × 0.6–0.7 mm, with very faint transverse ridges or wrinkles.

Phenology: Flowering and fruiting late spring–fall.
Habitat: Deep, sandy riverbanks.
Elevation: 600 m.


V12 777-distribution-map.jpg

Tex., Mexico (Chihuahua, Coahuila).


Euphorbia golondrina was first collected on a sandy riverbank at the entrance of Boquillas Canyon on the Texas/Mexico border, and the species appears to be restricted to the vicinity of the Rio Grande in western Texas and northern Mexico. Aside from the type locality at Boquillas Canyon, E. golondrina has been documented from additional locations along the Rio Grande in Brewster, Hudspeth, and Presidio counties in Texas and from northern Coahuila and Chihuahua, Mexico. Phylogenetic data place E. golondrina in a clade of primarily Chihuahuan desert annual and perennial herbaceous species (for example, E. chaetocalyx, E. fendleri, E. perennans, E. simulans, E. spurca, and E theriaca; Y. Yang and P. E. Berry 2011). Euphorbia golondrina is superficially similar to other glabrous species in western Texas (for example, E. micromera and E. theriaca), but E. micromera and E. theriaca either lack involucral gland appendages or have shorter, triangular appendages compared to the typical semilunate appendages in E. golondrina.

Selected References


Lower Taxa

... more about "Euphorbia golondrina"
Victor W. Steinmann +, Jeffery J. Morawetz +, Paul E. Berry +, Jess A. Peirson +  and Ya Yang +
L. C. Wheeler +
Anisophyllum +
Canyon or swallow spurge +  and Boquillas sandmat +
Tex. +, Mexico (Chihuahua +  and Coahuila). +
600 m. +
Deep, sandy riverbanks. +
Flowering and fruiting late spring–fall. +
Proc. Biol. Soc. Wash. +
Conservation concern +
Chamaesyce golondrina +
Euphorbia golondrina +
Euphorbia sect. Anisophyllum +
species +