Nigel P. Taylor

The genera of Cactaceae: progress towards consensus

Summary. After further debate and a postal ballot of specialists, the IOS Working Party has revised its 1986 ‘consensus’ list of accepted genera. The new list totals 93, i.e. seven more than that of 1986. The synopsis of genera is accompanied by a comprehensive index of generic names, an explanation of the ballot procedure and edited commentary on the proposals ballotted, summaries of recently published tribal classifications, and relevant bibliography.

The genus Melocactus (Cactaceae) in Central and South America

Summary. Melocactus Link & Otto (31 spp.) is revised in Central and South America to include 24 species and 10 heterotypic subspecies, arranged in 6 species-groups primarily on the basis of fruit, seed and spination characters: M. oreas Group incl. M. oreas (2 subspp.), M. ernestii (2 subspp.), M. bahiensis (2 subspp.), M. conoideus; M. deinacanthus Group (1 sp.); M. levitestatus Group (1 sp.); M. azureus Group incl. M. azureus (2 subspp.), M. pachyacanthus (2 subspp.); M. violaceus Group incl. M. salvadorensis, M. zehntneri, M. lanssensianus, M. glaucescens, M. concinnus, M. paucispinus, M. violaceus (3 subspp.), M. neryi, M. smithii; M. curvtspinus Group incl. M. estevesii, M. mazelianus, M. schatzlii, M. andinus (sp. nov.), M. bellavistensis (2 subspp.), M. peruvianus and M. curvispinus (3 subspp.). There are 18 species in eastern and Amazonian Brazil (16 endemic), 3 in the region of the Guianas and Venezuelan/Colombian llanos, and 4 endemic to the central and northern Andes. Only one, polymorphic species, M. curvispinus, is recognized in Central America (incl. Mexico) and ranges southeastward into northern Colombia and northern Venezuela (also in Cuba). The relationships of the genus and species-groups are analyzed cladistically. A comprehensive survey of seed-morphology is presented together with keys to species and infraspecific taxa, descriptions, ecological data, distribution maps, cladograms, colour and halftone illustrations, a list of new names and an index to specific epithets. The remaining 7 Caribbean species of Melocactus, which have not been revised, are briefly treated in an appendix. Zusammenfassung. Die Arten der Gattung Melocactus (Cactaceae) in Mittel- und Südamerika. Die mittel- und südamerikanischen Arten der Gattung Melocactus Link & Otto (31 Arten) werden revidiert; im Gebiet umfasst die Gattung 24 Arten und 10 heterotypische Unterarten, die v.a. aufgrund von Frucht- und Samen-Merkmalen sowie der Bedornung zu 6 Artengruppen zusammengefasst werden: Die M. OREAS-Gruppe mit M. oreas (2 ssp.), M. ernestii (2 ssp.), M. bahiensis (2 ssp.), M. conoideus; die M. deinacanthus-Gruppe (einzige Art); die M. Levitestatus-Gruppe (einzige Art); die M. Azureus-Gruppe mit M. azureus (2 ssp.), M. pachyacanthus (2 ssp.); die M. Violaceus-Gruppe mit M. salvadorensis, M. zehntneri, M. lanssensianus, M. glaucescens, M. concinnus, M. paucispinus, M. violaceus (3 ssp.), M. neryi, M. smithii; die M. Curvispinus-Gruppe mit M. estevesii, M. mazelianus, M. schatzlii, M. andinus (sp. nov.), M. bellavistensis (2 ssp.), M. peruvianus und M. curvispinus (3 ssp.). 18 Arten kommen in Ostbrasilien und Amazonien vor (davon sind 16 endemisch), 3 Arten stammen aus dem Gebiet der Guianas und der Venezolanisch-kolumbian-ischen Llanos, und 4 Arten sind in den zentralen und nördlichen Anden endemisch. In Mittelamerika (inkl. Mexiko) wir nur eine einzige polymorphe Art, M. curvispinus, anerkannt, die im Südosten bis ins nördliche Kolumbien und Venezuela verbreitet ist (ebenfalls in Kuba). Die verwandtschaftlichen Beziehungen der Gattung und Artengruppen werden kladistisch untersucht. Die Arbeit wird ergänzt durch einen umfassenden Überblick ¨ber die Samenmorphologie der Gattung, durch Schlüssel zu den Arten und infraspezifischen Taxa, Beschreibungen, ökologische Angaben, Verbreitungs-karten, Kladogramme, Abbildungen (farbig und schwarz/ weiss), sowie einer Liste neuer Namen und einem Index der Artnamen. Die verbleibenden 7 karibischen Arten von Melocactus, die nicht revidiert wurden, werden in einem Anhang kurz behandelt.

Notes on miscellaneous genera of Cactaceae (2)

Summary. Further taxonomic and nomenclatural notes are provided on various genera of Cactaceae. Proposals include the treatment of Pilocereus subg. Oblongicarpi (Croizat) Croizat (Subpilocereus Backeberg) and Mirabella Ritter as subgenera of Cereus and confirmation of the generic status of Pseudoacanthocereus Ritter. The application of various specific names is discussed along with miscellaneous questions of typification, orthography and citation.

A review of Ferocactus Britton & Rose

Summary. n A systematic treatment of Ferocactus Britton & Rose sensu stricto is presented. Following guidelines outlined in an earlier paper (Taylor & Clark, 1983) the species comprising subg. Ferocactus are arranged in two sections and four informal groups. In total 23 species and 20 heterotypic infraspecific taxa are included, with their authorities, places of publication, types, essential synonyms and distributional data. Brief diagnostic descriptions are provided to supplement the key to species and to enable identification of infraspecific taxa. References to good published illustrations are cited as an additional aid to recognition.

Additions and corrections to ‘Cacti of Eastern Brazil’

Summary: The inventory of taxa for the Cacti of Eastern Brazil area is updated and various extensions of geographical range noted. 24 additional species are now recognized for the region.

Additional notes on some Ferocactus species

Summary. n Brief notes, supplementing and emending the authors ‘Review of Ferocactus’ (1984), are presented for 7 species, based on recent field studies. F. lindsayi is reclassified in F. sect. Ferocactus, F. pottsii Group.

Seed-morphology and classification in Ferocactus subg. Ferocactus

Summary. n Seed-micromorphology of 31 species of Ferocactus was investigated in order to determine whether it would suggest relationship where gross morphology did not. A remarkable correlation between characters of the hilum-micropylar rim (HMR) and fruit is reported and used to circumscribe two sections within subgenus Ferocactus. Bisnaga Orcutt is resurrected for the section with juicy fruits and shiny seeds with narrow HMR. F. robustus and F. flavovirens each have the least derived suite of characters within their respective sections. The most derived species have tabular-concave testa-cells and are grouped separately on this basis. The determination of species limits may also be aided by investigation of seed morphology.