Abstract Detail

Systematics Section / ASPT

Elisens, Wayne [1], Hoagland, Bruce [3], Diggs, George [2].

Plant Geography of the Red River Basin: NM, TX, OK, AR, and LA.

The ecological and plant diversity of the Red River Basin is high reflecting the river's passage through three of Takhtajan’s floristic provinces: the Prairie province, the Appalachian province in the Ouachita Highlands region, and the Gulf Coastal Plain province. There are at least six species and two infraspecific taxa whose ranges are restricted to the 94,450 square miles comprising the Red River hydrologic basin (Polymnia cossatotensis, Valerianella palmeri, Eriogonum correllii, Lesquerella angustifolia, Phlox longipilosa, Streptanthus squamiformis, Monarda fistulosa var. stipitatoglandulosa, and Alnus maritima subsp. oklahomensis) as well as two species that are widely disjunct to other areas of high endemism in the Appalachian and Coastal Plain provinces (Calamovilfa arcuata and Alnus maritima). At least 12 additional species are 'almost' endemic to the Red River basin and have outlying populations in the adjacent Arkansas River basin. The Red River apparently serves as a barrier to the Oklahoma endemic species Penstemon oklahomensis, and its riparian habitats and sandy soils function as a two-way corridor for plant species to extend their ranges westward from the Coastal Plain and Appalachian provinces and eastward from the Rocky Mountain and Sonoran provinces. We encourage focused botanical collecting in the middle and upper reaches of the basin and further investigations to elucidate regional floristic and biogeographic patterns.

1 - University of Oklahoma, Botany & Microbiology and Oklahoma Biological Survey, 770 Van Vleet Oval, Norman, Oklahoma, 73019, USA
2 - Austin College, Biology, Sherman, Texas, 75090
3 - University of Oklahoma, Geography and Oklahoma Biological Survey, Norman, Oklahoma, 73019, USA

Keywords:
phytogeography
endemism
disjunction.

Presentation Type: Paper
Session: 24-6
Location: Cottonwood A (Snowbird Center)
Date: Monday, August 2nd, 2004
Time: 5:00 PM
Abstract ID:371