Quercus sinuata var. breviloba

(Torrey) C. H. Muller

in I. M. Johnston, J. Arnold Arbor. 25: 439. 1944.

Illustrated
Basionym: Quercus obtusifolia var. breviloba Torrey in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 206. 1859 Quercus annulata Buckley 1860(1861)
Synonyms: Quercus breviloba (Torrey) Sargent Quercus durandii var. breviloba (Torrey) E. J. Palmer Quercus durandii var. san-sabeana (Buckley ex M. J. Young) Buckley Quercus san-sabeana
Treatment appears in FNA Volume 3.

Shrubs or trees, rarely small, usually moderate, (0.5-)1-3(-5) m, often clonal with multiple trunks. Leaves: petiole 2-3 mm. Leaf blade (25-)30-60(-100) × (15-)20-40(-60) mm. Acorns: cup saucer-shaped to shallowly cup-shaped, rarely deeper, to 3-8 mm deep × 8-12 mm wide, enclosing 1/4 nut, rarely more, base flat, rounded, or constricted, margin thin; nut depressed-ovoid to oblong, 7-12(-15) × 7-10 mm, glabrous.


Phenology: Flowering spring.
Habitat: Open oak woodlands, dry scrublands, margins of grasslands, and along streams and arroyos, on limestone, rarely on granitics
Elevation: 200-600 m

Distribution

V3 1066-distribution-map.gif

Okla., Tex., Mexico (Coahuila, Nuevo León, and Tamaulipas).

Discussion

Quercus sinuata var. breviloba replaces var. sinuata on the Edwards Plateau of Texas and extends south at lower elevations along the eastern side of Sierra Madre Oriental in northern Nuevo León and Tamaulipas. Although habitats of these two varieties are very different, along streams through limestone hills in central Texas the two varieties are in contact, and numerous problematic, morphologically intermediate forms may be found. The lack of broad geographic sympatry and intergradation argue for the treatment of these two taxa at varietal rank.

Selected References

None.

Lower Taxa

None.
Kevin C. Nixon +  and Cornelius H. Muller +
(Torrey) C. H. Muller +
Quercus obtusifolia var. breviloba +  and Quercus annulata +
Okla. +, Tex. +, Mexico (Coahuila +, Nuevo León +  and and Tamaulipas). +
200-600 m +
Open oak woodlands, dry scrublands, margins of grasslands, and along streams and arroyos, on limestone, rarely on granitics +
Flowering spring. +
in I. M. Johnston, J. Arnold Arbor. +
Illustrated +
Quercus breviloba +, Quercus durandii var. breviloba +, Quercus durandii var. san-sabeana +  and Quercus san-sabeana +
Quercus sinuata var. breviloba +
Quercus sinuata +
variety +