Stipeae
The Stipeae are a tribe of grasses within the subfamily Pooidae, with up to 600 described species.[1] The defining morphological features of the Stipeae include single-flowered spikelets lacking a rachilla extension, and the lemmas (the external bract) have either a sharp point or a terminal awn (long bristle).[2]
The tribe includes the genera Austrostipa, Nassella, Jarava, Stipa, Achnatherum, Piptatherum, Piptochaetium, Aciachne, and Hesperostipa. Many species were initially placed into Stipa but have now been split off into new genera. Some recent papers have analysed relationships within and between genera[3][4][5] although a complete analysis has not yet been completed. Stipoid grasses use the C3 (cool season) photosynthetic pathway and live in temperate areas worldwide.[6] Known fossils date from the late Miocene.[7]
References
- ^ Barkworth ME, Arriaga MO, Smith JF, Jacobs SWL, Valdes-Reyna J, Bushman BS (2008) Molecules and Morphology in South American Stipeae (Poaceae). Systematic Botany 33(4), 719-731.
- ^ Cialdella AM, Giussani LM, Aagesen L, Zuloaga FO, Morrone O (2007) A phylogeny of Piptochaetium (Poaceae : Pooideae : Stipeae) and related genera based on a combined analysis including trnL-F, rp116, and morphology. Systematic Botany 32(3), 545-559.
- ^ Barber JC, Hames KA, Cialdella AM, Giussani LM, Morrone O (2009) Phylogenetic relationships of Piptochaetium Presl (Poaceae: Stipeae) and related genera reconstructed from nuclear and chloroplast sequence datasets. Taxon 58(2), 375-380.
- ^ Jacobs SWL, Bayer R, Everett J, Arriaga MO, Barkworth ME, Sabin-Badereau A, Torres MA, Vazquez FM, Bagnall N (2007) Systematics of the tribe Stipeae (Gramineae) using molecular data. Aliso 23, 349-361.
- ^ Jacobs SWL, Everett J, Barkworth ME, Hsiao C (2000) Relationships within the Stipoid grasses (Gramineae). In 'Grass Systematics and Evolution.' (Eds SWL Jacobs and J Everett) pp. 75-82. (CSIRO: Melbourne)
- ^ Romaschenko K, Peterson PM, Soreng RJ, Garcia-Jacas N, Futorna O, Susanna A (2008) Molecular phylogenetic analysis of the American Stipeae (Poaceae) resolves Jarava sensu lato polyphyletic: evidence for a new genus, Pappostipa. Journal of the Botanical Research Institute of Texas 2(1), 165-192.
- ^ Thomasson JR (2005) Berriochloa gabeli and Berriochloa huletti (Gramineae: Stipeae), two new grass species from the late Miocene Ash Hollow Formation of Nebraska and Kansas. J Paleontol 79 (1):185-199