The yew family (Hils 1993), Taxacées [French], Eibengewächse [German], taxáceas [Spanish], Тисовые [Russian], 红豆杉科 hong dou shan ke [Chinese], イチイ科 [Japanese].
A family of 6 genera and 28 species, mainly in the northern hemisphere:
The taxaceous conifers are generally regarded as being distinct from the other conifers; many authors have assigned them to a distinct Order, Taxales Knobl. 1890, and they have also been placed in a distinct Suborder, Taxineae Luerss. 1879, or have even been segregated at the Subclass rank as Taxidae Ehrend. ex Reveal 1996. The family seems to have arisen via a whole-genome-duplication (polyploidy) event that separated it, in a clade that included the progenitor of both the Cupressaceae and the Taxaceae, from the remaining conifer lineages (a similar event gave rise to the Pinaceae clade, and to the Welwitschiaceae) (Li et al. 2015).
Within the Taxaceae, some authors have assigned Amentotaxus to a separate family (Amentotaxaceae Kud et Yamam. 1931), likewise Austrotaxus (Austrotaxaceae Nakai 1938), Cephalotaxus (Cephalotaxaceae Neger 1907), and Torreya (Torreyaceae Nakai 1938). Relationships within the family were elucidated by Hao et al. (2008), who used both chloroplast and nuclear DNA markers to analyze all generally recognized species in the Taxaceae inclusive of Cephalotaxus. Their analysis showed that the clade of Cephalotaxus with other Taxaceae genera is monophyletic. They also showed that the ancestral distribution of the family is centered in southwest or southeast China.
Evergreen trees or shrubs, usually neither resinous nor aromatic (sharp- or foul-odored in Torreya), dioecious or monoecious. Bark scaly or fissured. Lateral branches well developed, similar to leading shoots; twigs terete, not densely clothed by leaves but ± ridged by decurrent leaf bases; longest internodes less than 1 cm; buds ± inconspicuous. Roots fibrous to woody. Leaves (needles) simple, persisting several years, shed singly, alternate [opposite], spirally arranged but often twisted so as to appear 2-ranked, linear to linear-lanceolate, decurrent; resin canals present or absent. Pollen cones maturing and shed annually, solitary or clustered, axillary on year-old branches, globose to ovoid, sporophylls bearing 2 - 16 microsporangia (pollen sacs); pollen ± spheric, not winged. Seed cones reduced to 1 - 2 ovules subtended by inconspicuous, decussate bracts, maturing in 1 - 2 seasons, axillary on year-old branches. Seeds 1 per "cone," erect, not winged, hard seed coat partially or wholly surrounded by a juicy, fleshy or leathery aril; cotyledons 2. Wood without resin ducts (Silba 1986, Hils 1993). All investigated species form a vesicular-arbuscular mycorrhiza (Brundrett 2008 and citations therein).
Europe: Britain to N Iran. Asia: USSR, Korea, Japan, China, Taiwan, Himal, India, Burma, Vietnam, Philippines. New Caledonia. N America: SE AK to CA, E Canada, E USA, FL, Mexico, Guatemala, El Salvador. S America.
The family has been around quite a while. It includes at least one extinct genus, Kakahuia, reported from the Eocene and early Miocene of southern New Zealand (Pole 2007).
Brundrett, Mark. 2008. Mycorrhizal Associations: The Web Resource. mycorrhizas.info, accessed 2009.06.09.
Gray, S.F. 1821. A Natural Arrangement of British Plants. London: Baldwin, Cradock & Joy. Vol. 2, pp.222 & 226. Available: http://www.algaebase.org/pdf/AC100CF1119491BDE4HTS3F57634/A_natural_arrangement_of_British_plants.pdf, accessed 2011.01.14.
Li, Zheng, Anthony E. Baniaga, Emily B. Sessa, Moira Scascitelli, Sean W. Graham, Loren H. Rieseberg, and Michael S. Barker. 2015. Early genome duplications in conifers and other seed plants. Science Advances 1(10):e1501084.
Cheng Y., Chaw S., R. Nicholson and K. Tripp. 2000. Phylogeny of Taxaceae and Cephalotaxaceae genera inferred from chloroplast matK gene and nuclear rDNA ITS region. Molecular Phylogenetics and Evolution 14 (3): p. 353-365.
Florin, R. 1948. On the morphology and relationship of the Taxaceae. Botanical Gazette 110:31-39.
Krüssmann, G. 1972. Handbuch der Nadelgehölze. Berlin.
Last Modified 2017-12-29