Saturday, January 01, 2000

Online Articles

John M. Coulter
A Preliminary Revision of the North American Species of Cactus, Anhalonium, and Lophophora.
Vol. III No. 2, 1894

My local copy of the article contains Coulter's proposal for a new genus for peyote alone: Lophophora. The full, unformatted text can be found as a Project Gutenberg Etext, also an abridged (the sections relating to Ariocarpus/Anhalonium species are reproduced), formatted version of the article is available at Living Rocks of Mexico.

Curtis's Botanical Magazine

Flora of North America
The Flora of North America provides an account of American plant species north of Mexico. Below I have included the descriptions for a list of species relevant to this site.

Butterworth, C. A. & J. H. Cota-Sanchez, & R. S. Wallace
Molecular systematics of Tribe Cacteae (Cactaceae: Cactoideae): A phylogeny based on rpl16 intron sequence variation.
Systematic Botany 27(2), 2002: 257-270

The paper documents the close relationship among Acharagma, Lophophora and Obregonia. Based on DNA evidence the species are placed in a well-supported clade (the Lophophora Clade).

ABSTRACT. Parsimony analysis of plastid rpl16 sequences from 62 members of Tribe Cacteae, and four outgroup taxa yielded 1296 equally parsimonious trees of length 666. Strict consensus evaluation of these trees established a highly pectinate topology, which delimited clades within the tribe that correspond to several previously considered generic groups. Aztekium and Geohintonia, which manifest ribs in their stem morphology were shown to represent an early divergence in the tribe, forming a sister group to remaining members of the tribe. Clades containing other genera having ribbed stems also are basal to those that develop tubercles. The most derived clade forms a distinct group of typically small stemmed species with tubercular stem morphology. Within Mammillaria, species formerly placed in the genus Cochemiea and members of the Series Ancistracanthae formed a well-supported, sister clade to the remaining members of Mammillaria. Length variation of the intron in two members of Mammillaria series Stylothelae was also observed.

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