Abstract Detail

Donald J. Pinkava's legacy - the ASU Herbarium in the Sonoran Desert

Daniel, Thomas [1].

Don Pinkava and the Vascular Flora of the Cuatro Ciénegas Basin in the Chihuahuan Desert.

In 1967 Don Pinkava began botanical exploration of the then little-studied Bolsón de Cuatro Ciénegas in the east-central portion of the Chihuahuan Desert. This closed (i.e., internally drained) basin contains a unique assemblage of biotic communities in a relatively small region. Following 10 years of field studies, between 1979 and 1984 Pinkava published catalogs of the vascular flora of his 2,000 sq. km study area, and documented 860 species in 456 genera from 114 families. He also recognized and summarized eight biotic communities in the study area: aquatic and semiaquatic habitats, gypsum dunes/flats, basin grasslands, transition zone (between grasslands and desertscrub), desertscrub, chaparral, oak-pine and oak woodlands, and montane conifer forests. The flora area encompasses the type locales for at least 49 taxa, 23 of which were treated as endemic there. Notable endemics include several gypsophiles (e.g., Phacelia marshalljohnstonii, Tiquilia turneri, Dyssodia gypsophila, Gaillardia gypsophila, Haploesthes robusta, and Machaeranthera restiformis) and the now widely cultivated mint, Poliomintha maderensis. Pinkava authored or co-authored four new species from the flora area. Families with the most species listed in the ultimate floristic summary are Asteraceae (125 spp.), Poaceae (76), Fabaceae (47), and Cactaceae (50); each of these families except Poaceae contains one or more species endemic to the Cuatro Ciénegas Basin. The botanical richness of this region is amply illustrated by Acanthaceae. In that family, 36 species in 12 genera occur in the Chihuahuan Desert, and 20 of those species (56%) are endemic to it. Thirteen species in six genera of Acanthaceae occur in the flora area—36% of species and half of the genera known from the entire >400,000 sq. km Chihuahuan Desert region. Possessing six of the 10 Chihuahuan Desert species of the acanthaceous genus Carlowrightia (25 spp), the Cuatro Ciénegas Basin has the highest concentration of species in that genus. In his publications, Pinkava extolled the distinctive aquatic habitats, botanical richness/endemism, and scenic value of the basin; listed apparent threats to the landscape; and urged preservation of the regions' unique ecosystems. Thanks, in part, to his botanical inventory of the basin, and the contributions of other biologists working there, the Área de Protección de Flora y Fauna Cuatrociénegas was established in 1995. A portion of the region became a UNESCO Biosphere Reserve in 2006.

1 - California Academy of Sciences, Botany, 55 Music Concourse Drive, San Francisco, CA, 94118, United States

Keywords:
Don Pinkava
Cuatro Ciénegas Basin
Chihuahuan Desert
Floristics
endemism.

Presentation Type: Colloquium Presentations
Session: CO10, Donald J. Pinkava’s legacy - the ASU Herbarium in the Sonoran Desert
Location: San Pedro 2/Starr Pass
Date: Wednesday, July 31st, 2019
Time: 8:30 AM
Number: CO10002
Abstract ID:143
Candidate for Awards:None