Chromosome numbers in Chihuahuan Desert Cactaceae. Trans-Pecos Texas
Weedin JF and Powell AM. 1978. Chromosome numbers in Chihuahuan Desert Cactaceae. Trans-Pecos Texas. American Journal of Botany. 65(5):531-537
Chromosome numbers are presented for 100 collections of Cactaceae from the Trans-Pecos region of Texas. A total of 65 taxa representing 52 species and 12 genera were counted, including first reports for 45 taxa and new ploidy levels for four taxa. Notable among those listed are counts for Opuntia schottii var. grahamii (n = 11, ca. 22), O stanlyi (n = 22), O. arenaria (n = 11), O. phaeacantha var spinosibacca (n = 22), O lindheimeri var. lindheimeri (n = 11), O strigil (n = 11), Echinocereus enneacanthus var. cf dubius (n = ca. 22), E. pectinatus var neomexicanus (n = 22), and Thelocactus bicolor var. bicolor (n = 22). Endomitosis was found to be present in O. phaeacantha var spinosibacca, Mammillaria pottsii, and Neolloydia intertexta var. dasyacantha. Meiotic irregularities were noted in some species belonging to the genera Opuntia and Echinocereus. Phytogeographic considerations are inferred from the chromosomal data for O polyacantha, O. lindheimeri, and O. ficusindica A base number of x = 11 in Cactaceae is supported
- Type
- Journal Article
- Authors
- Weedin, James; Powell, A
- Units
- BIBE
- Keywords
- Cactaceae, chromosome numbers, Trans-Pecos Texas, Vegetation