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Map of central Baja California showing the Vizcaíno Peninsula, Baja California Sur and Baja California, Mexico, and localities of Agave species. San Igancio is the type locality for A. cerulata ssp. cerulata, hence the green marker for the town's location is obscured by pink squares. Small black dots are sampling localities where agaves were not observed.
Source publication
Agave azurea, a new species of Agave from the Picachos de Santa Clara, Baja California Sur, Mexico, is a medium-sized species with distinctive glaucous blue-green leaves that does not produce offsets, has a relatively short and narrow inflorescence, and a distinctive flower structure. The closest relative to this new species is Agave vizcainoensis,...
Contexts in source publication
Context 1
... were drawn to the Vizcaíno peninsula, in northwestern Baja California Sur (Fig. 1), because of some anomalies in herbarium specimens and what appeared to be a unique species in the Picachos de Santa Clara. In his exsiccatae, Gentry (1978) reports herbarium specimens (Gentry 7693, 7713) submitted to the University of Arizona Herbarium with dupli- cates in several other herbaria, that are assigned to both Agave ...
Context 2
... de Santa Clara, Gentry (1982: 407) states: "The plants growing about the Picachos de Santa Clara are more robust and less sur- culose than those in the Sierra Vizcaíno proper and resemble A. gigantensis." Another set of herbarium specimens (Moran 5263-25269, SD) reports Agave sebastiana on Cerro Prieto, southwest of the Picachos de Santa Clara (Fig. 1). Other specimens, purported- ly of Agave sebastiana (e.g., AGA1212810, MEXU), were collected in the vicinity of Bahía Tortugas north to Punta ...
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... total of 6 species with 2 varieties occur within 200 km of the Picachos de Santa Clara (Fig. 1). To the northwest, Agave vizcainoensis Gentry commonly occurs in the Sierra Vizcaíno and other low moun- tains on the Vizcaíno Peninsula. Agave sebastiana Greene occurs on Isla Cedros, Isla San Benito, Isla Natividád, and reportedly also north of Bahía Tor- tugas (Gentry 1978). A. avellanidens (Trel.) Gentry, A. cerulata ssp. cerulata ...
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... and climate-This species appears to be restricted to rocky colluvial hillslopes and al- luvial fans in the Picachos de Santa Clara on the Viz- caíno Peninsula, Baja California Sur, Mexico (Figs. 1, 6). We did not find Agave azurea on sandy soils west of the type locality nor in the sandy plains to the east. ...
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... previously noted, six species occur within 200 km of the Picachos de Santa Clara (Fig 1). Because Agave avellanidens and A. cerulata are quite differ- ent from and have not been confused with Agave vizcainoensis, A. gigantensis, and A. sebastiana, only the latter three will be considered here in relation to Agave azurea. ...
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... vizcainoensis (Fig. 8) is a highly variable species that Gentry (1978) described from the Sierra de Vizcaíno in the west-central part of the Vizcaíno Peninsula. On 19 February 1978, Reid Moran climbed the slopes of Cerro Prieto, southwest of the Picachos de Santa Clara (Fig. 1), and collected speci- mens that he believed were of Agave sebastiana (Moran 25263-25269, SD). We visited Cerro Prieto on 20 April 2013 and examined the plants found there (Fig. 9). Although the plants in this population were vari- able in leaf number and degree of undulation in the leaf margin, they resembled plants in a population of ...
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... sebastiana was the focus of a trip to Isla Cedros in May 2011, and plants were examined at several localities on the island. The plants were soli- tary to offsetting and formed large colonies; had nu- merous, glaucous gray leaves ( Fig. 10) with relatively straight margins and numerous teeth; had a short, acute tip below the stout terminal spine, which was decurrent to the fifth or sixth pair of teeth; and had relatively short, wide inflorescences as befitting the Umbelliflorae. These plants agree with the published descriptions of A. sebastiana (restated in Gentry ...
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... vizcainoensis on the Vizcaíno Peninsula warrant fur- ther investigation, and we have redefined the dis- tributions of the previously identified species that are known from this peninsula and its off-shore is- lands. We conclude that Agave sebastiana, as it was originally described, only occurs on Isla Cedros, Isla Natividád, and Islas San Benito (Fig. 1). Agave viz- cainoensis is the most widely distributed Agave on the Vizcaíno Peninsula, and additionally, plants on Cerro Prieto are an unusual form. After further investiga- tion, we found only Agave vizcainoensis in the west- ern mountains of the Vizcaíno Peninsula and north of Bahía Tortugas. Further, we have determined that A. ...
Similar publications
In 1978, Howard Scott Gentry published his second monograph on the genus Agave focusing on the plants of the peninsula of Baja California, México, and the related species in the group Deserticolae in the US and Sonora. We revisit Gentry's work with an emphasis on revising the genus and its taxonomic arrangement and including several recently descri...
Citations
A diagnostic description of the genus is given with special emphasis on the occurrence of succulence amongst its species. The geographical distribution is outlined, together with a selection of important literature, and an explanation of the etymology of the name. This is followed by a short summary of its position in the phylogeny of the family and of the past and present classification in a phylogenetic context. The succulent features present amongst the species of the genus are shortly explained as to morphology and anatomy.
This is followed by a synoptical treatment of the species (all succulent) of the genus, complete with typification details, full synonymy, geographical and ecological data, a diagnostic description, and, where applicable, notes on phylogenetic placement and relationships, as well as economic and/or horticultural importance.
A diagnostic description of the genus is given with special emphasis on the occurrence of succulence amongst its species. The geographical distribution is outlined, together with a selection of important literature, and an explanation of the etymology of the name. This is followed by a short summary of its position in the phylogeny of the family and of the past and present classification in a phylogenetic context. The succulent features present amongst the species of the genus are shortly explained as to morphology and anatomy.
This is followed by a synoptical treatment of the species (all succulent) of the genus, complete with typification details, full synonymy, geographical and ecological data, a diagnostic description, and, where applicable, notes on phylogenetic placement and relationships, as well as economic and/or horticultural importance.
In 1978, Howard Scott Gentry published his second monograph on the genus Agave focusing on the plants of the peninsula of Baja California, México, and the related species in the group Deserticolae in the US and Sonora. We revisit Gentry's work with an emphasis on revising the genus and its taxonomic arrangement and including several recently described species from this Mexican peninsula known for its high plant endemism. A total of 23 Agave taxa occur on the peninsula, 22 of which are endemic. We change Gentry's treatment of four groups into six sections formally defined to better segregate species based on shared inflorescence characteristics. We eliminate one variety, revert one variety to species status, change two species to subspecies or varieties, and reduce one subspecies to a variety. We present high spatial resolution maps of the distribution of these species as well and correct some of the previous identifications of herbarium specimens. Extensive field work suggests that taxonomic problems remain in the Agave sobria complex of the Sierra de la Giganta, where as many as three additional taxa could be described from the array of variation we observed. As well, the distributional overlap of Agave avellanidens and Agave shawii ssp. goldmaniana remains problematic owing to similar vegetative characteristics but greatly differing inflorescences.
