EurekaMag.com logo
+ Site Statistics
References:
47,893,527
Abstracts:
28,296,643
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Systematics of the Echinocactus polycephalus complex (Cactaceae)


, : Systematics of the Echinocactus polycephalus complex (Cactaceae). Systematic Botany 22(2): 303-313

Three morphologically similar North American barrel cacti comprise the Echinocactus polycephalus complex, here defined as including E. parryi, E. polycephalus var. polycephalus, and E. polycephalus var. xeranthemoides. The relationship of E. parryi to E. polycephalus has been suggested without critical examination. The varieties of E. polycephalus have been elevated to species rank by some taxonomists; however existing keys have shown inadequacies separating these taxa in the field, and distribution maps have indicated potential sympatry among them. Herbarium studies, field observations, scanning electron microscopy, and phenetic analysis are here used to support the distinction of E. parryi and E. polycephalus as separate species. The varietal ranking of E. polycephalus var. xeranthemoides is also supported. The varieties of E. polycephalus are distinguished by seed and hypanthium scale morphology. Their distributions are parapatric, with evidence of hybridization and potential introgression. The records of Pleistocene-age seed macrofossils of E. polycephalus are summarized. Echinocactus parryi and E. polycephalus are herein lectotypified.

Accession: 003292147

DOI: 10.2307/2419459

Download PDF Full Text: Systematics of the Echinocactus polycephalus complex (Cactaceae)


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Related references

Rowland, D.D.niel, J., 1976: Echinocactus polycephalus

Wallace R.S., 1991: Cactus molecular systematics chloroplast dna variation in the genera astrophytum lem and echinocactus link and otto cactaceae cacteae. American Journal of Botany 78(6 SUPPL): 227

Lux, A.; Mikus, M.; Hanackova, Z.; Kristin, J., 1994: Radicle of Echinocactus platyacanthus (Cactaceae). Mature dry embryos were isolated from E. platyacanthus seeds collected in Mexico and light microscopy, TEM and X-ray microanalysis were used to study the histology, cell structure and globoid crystals of the radicle. The radicle of a mature embryo...

Mosco, A.; Zanovello, C., 1999: Proposal to reject the name Echinocactus smithii (Cactaceae). It is suggested that the original description of Echinocactus smithii refers to Thelocactus conothelos. Therefore, to avoid the need to publish new combinations and to maintain nomenclatural stability, it is proposed that the name E. smithii be re...

Anonymous, 1953: Studies of South American Cactaceae 2 Echinocactus humilis Philippi

Rio, Z.C. del; Maiti, R.K.; Flores Zaval, J.G.; Herandez Jose, M.; Esteban, A.; Velez Soto, A.; Perez Santa, F., 2003: Evaluation of two treatments on germination of Echinocactus grusonii (Cactaceae) in Xocoyucan, Tlaxcala, Mexico. The effects of two treatments on the germination of E. grusonii seeds were investigated. Pre-treatment with warm water at 50 degrees C gave higher germination (93%) compared to direct sowing on sand substrate (67%).

Del Castillo R.F.; Trujillo S., 1991: Ethnobotany of ferocactus histrix and echinocactus platyacanthus cactaceae in the semiarid central mexico past present and future. Ferocatus histrix and Echinocactus platyacanthus are two common barrel cacti of the semiarid highland of Central Mexico. In pre-Columbian times, these plants were sacred, used for sacrifices, food and medicine. Today, these cacti are used in the c...

Rosas Lopez, U.; Collazo Ortega, M., 2004: Conditions for the germination and the early growth of seedlings of Polaskia chichipe (Goss.) Backeberg and Echinocactus platyacanthus Link and Otto fa. grandis (Rose) Bravo-Hollis (Cactaceae). The effect of different combinations of chemical scarification, soaking and substrates (ex vitro and in vitro) on seed germination of Polaskia chichipe (Goss.) Backeberg and Echinocactus platyacanthus Link & Otto fa. grandis (Rose) Bravo-Hollis,...

Zimmerman A.D., 1985: Systematics of seguieria phytolaccaceae? and pereskia cactaceae. American Journal of Botany 72(6): 977

P.A.Romeo, S.L.Stephenson, R.B.Clarkson, 1987: Systematics of Opuntia (Cactaceae) in the central Appalachians. Naturally occurring populations of Opuntia (Cacataceae) within the Ridge and Valley Province of the central Appalachian Mountains were investigated to determine if the cacti of this area are the widely distributed species O. compressa (Salisb.) Ma...