Seymeria bipinnatisecta

Stems puberulous to villous, glandular. Leaves: blade margins 2-pinnatifid, pinnules lanceolate, surfaces not scabrid. Pedicels 4–7 mm. Flowers: calyx lobes lanceolate, margins slightly dentate; corolla yellow, externally tomentose, internally glabrous except pubescent in a ring at stamen insertion; filaments glabrous distally, anthers dehiscing 1/2+ length. Capsules symmetric, pyriform, pubescent. Seeds ovoid, wings absent.

Phenology: Flowering and fruiting Jul–Oct.
Habitat: Rocky calcareous soils, shrubby grasslands, oak-juniper woodlands, mesic canyon bottoms, rock outcrops.
Elevation: 200–600 m.

Ariz., Tex., Mexico (Coahuila), Mexico (Durango), Mexico (Sinaloa), Mexico (Sonora)

Discussion

B. L. Turner (1982) circumscribed Seymeria bipinnatisecta as a variable species ranging widely from the Arizona and Texas borders through much of northwestern Mexico. In the flora area, the species extends into the Sierra Madre of southeastern Arizona and the Edwards Plateau of central and southwestern Texas. Morphological variation in this range is continuous with that of the Mexican specimens. Gray admitted that he had not seen Mexican specimens of S. bipinnatisecta but created var. texana based on perceived differences from the illustration of leaf and calyx incision, and of pedicel length by Seemann. Examination of specimens for this treatment indicates that the full range of diversity attributable to Mexican specimens for these characters can be found also in specimens of the Edwards Plateau. Most of the specimens collected in Texas are from the central Edwards Plateau; one clearly belonging to this species from Val Verde County on the Rio Grande (W. R. Carr 12406, TEX) is known; the range may not be discontinuous between Mexican and Edwards Plateau populations.

Selected References

None.

Lower Taxa