Euphorbia chaetocalyx var. triligulata

(L. C. Wheeler) M. C. Johnston

Wrightia 5: 139. 1975.

Common names: Triligulate bristlecup sandmat
Conservation concern
Basionym: Euphorbia fendleri var. triligulata L. C. Wheeler Bull. Torrey Bot. Club 63: 445. 1936
Synonyms: Chamaesyce chaetocalyx var. triligulata (L. C. Wheeler) Mayfield
Treatment appears in FNA Volume 12. Treatment on page 264. Mentioned on page 263.

Leaf-blades narrowly-ovate to linear-lanceolate, 3–11 × 0.8–3 mm. Involucral gland appendages straplike, divided into 3–5 linear segments, each 0.8–1.1 × 0.1 mm.


Phenology: Flowering and fruiting early summer–fall.
Habitat: Canyon walls, crevices in boulders.
Elevation: 600–900 m.

Discussion

Variety triligulata was described from the cliffs of Boquillas Canyon, on both sides of the Rio Grande in Texas and adjacent Coahuila, Mexico. The variety has elongate involucral gland appendages that are divided into three to five linear, straplike segments; it appears to represent a distinctive, localized population within the overall distribution of Euphorbia chaetocalyx. More generally, populations of E. chaetocalyx from elsewhere in northern Coahuila, Mexico, have similarly shaped involucral gland appendages and may represent additional populations of var. triligulata.

Selected References

None.

Lower Taxa

None.

"connate" is not a number. "distinct" is not a number."/2" is not declared as a valid unit of measurement for this property.

short-acuminate;acute +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
lanceolate-deltate +  and straplike +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
Victor W. Steinmann +, Jeffery J. Morawetz +, Paul E. Berry +, Jess A. Peirson +  and Ya Yang +
(L. C. Wheeler) M. C. Johnston +
short-tapered +
Euphorbia fendleri var. triligulata +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
ovate;lanceolate or oblong or linear-lanceolate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
depressed-ovoid +  and depressed-globose +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.24 cm2.4 mm <br />0.0024 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
Triligulate bristlecup sandmat +
divided +, cleft +, crenate +  and entire +
Tex. +  and Mexico (Coahuila) +
600–900 m. +
pistillate +  and staminate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (?) +
yellowbrown +  and reddish +
0.2mm;0.4mm +
subtending +
oval +, elliptic +, convex +  and concave +
0.4mm +  and 0.6mm +
Canyon walls, crevices in boulders. +
axillary +  and terminal +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
campanulate +  and turbinate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
narrowly-ovate;linear-lanceolate +
caducous +, deciduous +  and persistent +
bractlike +
palmate +  and pinnate +
toothed +  and entire +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
connate;distinct +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Flowering and fruiting early summer–fall. +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
smooth +  and slightly wrinkled +
4-angled +  and ovoid-pyramidal +
0.1 cm1 mm <br />0.001 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
rounded +
Conservation concern +
free +, connate +  and distinct +
flattened +  and terete +
3 cm30 mm <br />0.03 m <br /> (15 cm150 mm <br />0.15 m <br />) +
interpetiolar +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
connate +  and distinct +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +  and 0.04 cm0.4 mm <br />4.0e-4 m <br /> (?) +
Chamaesyce chaetocalyx var. triligulata +
Euphorbia chaetocalyx var. triligulata +
Euphorbia chaetocalyx +
variety +
axillary +  and terminal +
10 +, 9 +, 8 +, 7 +  and 6 +