Distephanus

Distephanus
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Asteraceae
Tribe: unplaced
Genus: Distephanus
Cassini
Type species
Distephanus populifolius
(Lamarck) Cassini
Species

See text

Distephanus is a genus of flowering plants in the family Asteraceae.[1] It is described by Harold Robinson as having over 40 species [1] and by David Mabberley as having only 34 species.[2] These sources differ sharply in their description of the range of the genus. Robinson has it ranging thruout Africa and occurring also in India and China. Mabberley has it restricted to southeast Africa, Madagascar, and Mauritius.

One of its species, Distephanus qazmi, was described only recently, in 2000.[3] The type species is Distepanus populifolius.[4]

The genus Distephanus consists of trees, shrubs, and vines. The leaves are often trinervate. The flowers are in terminal inflorescences and are usually yellow. The anthers have an appendage called a tail. The base of the style is enlarged.

The name Distephanus is derived from Greek and means "two crowns", a reference to the two whorls of bristles that form the pappus.[5]

The genus Distephanus was established by Alexandre de Cassini in 1817.[6] Cassini described the type species, Distephanus populifolia in 1819.[7] This species had originally been named Conyza populifolia by Jean-Baptiste Lamarck in 1786.[8]

Distephanus has usually been placed in the tribe Vernonieae, but the results of some molecular phylogenetic studies of DNA sequences have cast doubt upon this placement. In one classification of Asteraceae, it was placed in a tritomy consisting of Distephanus, Moquinieae, and Vernonieae.[9]

Distephanus differs from (other) genera in Vernonieae in having yellow flowers as well as in other characters that are less obvious.[10]

References

  1. ^ a b Harold E. Robinson. 2007. "Vernonieae" pages 149-174. In: Klaus Kubitzki (series editor); Joachim W. Kadereit and Charles Jeffrey (volume editors). The Families and Genera of Vascular Plants volume VIII. Springer-Verlag: Berlin; Heidelberg, Germany. ISBN 978-3-540-31050-1
  2. ^ David J. Mabberley. 2008. Mabberley's Plant-Book third edition (2008). Cambridge University Press: UK. ISBN 978-0-521-82071-4
  3. ^ Norbert Kilian and Anthony G. Miller. 2000. "Studies in the Compositae of the Arabian Peninsula and Socotra - 5. Distephanus qazmi (Vernonieae, Gymnantheminae), a remarkable new species from the island of Socotra, Yemen". Willdenowia 30(1):83-91.
  4. ^ Distephanus At: Index Nominum Genericorum In: Regnum Vegetabile. (see External links below).
  5. ^ Umberto Quattrocchi. 2000. CRC World Dictionary of Plant Names volume II:822. CRC Press: Boca Raton; New York; Washington, DC;, USA. London, UK. ISBN 978-0-8493-2676-9. (vol. 2). (see External links below).
  6. ^ Alexandre H.G. de Cassini. 1817. Bulletin des Sciences, par la Société Philomatique de Paris. (1817):151.
  7. ^ Alexandre H.G. de Cassini. 1819. Dictionnaire des Sciences Naturelles, ··· Strasbourg. edition 2. (F. Cuvier). 19:361.
  8. ^ Jean-Baptiste Lamarck. 1786. Encyclopedie Methodique. Botanique ··· Paris. 2(1):87.
  9. ^ Vicki A. Funk, Alfonso Susanna, Tod F. Stuessy, and Randall J. Bayer. 2009. Systematics, Evolution and Biogeography of the Compositae. IAPT (International Association for Plant Taxonomy). ISBN 978-3-9501754-3-1 (see External links below).
  10. ^ Harold E. Robinson. 1986. "Trinervate leaves, yellow flowers, tailed anthers, and pollen variation in Distephanus Cassini (Vernonieae: Asteraceae)". Proceedings of the Biological Society of Washington 99(3):493-501.

External links