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PodocarpaceaeCommon NamesPodocarp family, Taxonomic notesIn this treatment, 18 genera and 173 species. It has been treated as an order: Podocarpales Pulle ex Reveal 1992, and many of its constituent genera, including Nageia, Phyllocladus and Saxegothaea, have been raised to the rank of Family by previous authors. Most taxonomists seem to agree that Phyllocladus is the most atypical genus in the family, and it is often treated as Phyllocladaceae Bessey 1907. Many of the genera described here were originally lumped into the huge catchall genus Podocarpus or the also-very-large genus Dacrydium, and appear as such in much of the literature. Here is a brief and simplified chronology of how the podocarps have been subdivided at the generic rank:
DescriptionEvergreen shrubs or trees, usually with straight trunk and more or less horizontal branches. Leaves usually spirally arranged, sometimes opposite, scale-like, needle-like, or more apart, flat and leaf-like, linear to lanceolate. Monoecious or dioecious. Pollen cones usually catkin-like; stamens numerous, close together, imbricate, each with 2 sporangia; pollen grains usually winged. Female cones maturing in one year, much reduced to a few fleshy bracts or scales, pendant, usually borne on a thin peduncle, containing a single inverted ovule. Seeds completely covered by a fleshy structure referred to as an epimatium, wingless. Epimatium and integument sometimes connate and forming a leathery testa. Cotyledons 2, with 2 parallel vascular bundles (Van Royen 1979, Silba 1986). RangeThe family is predominantly found in the Australasian region, with most taxa native from New Zealand to SE Asia. Most of species are not of wide distribution, being confined to one or a few islands, viz. Tasmania, New Zealand, New Caledonia, New Guinea, Philippines, Borneo. Some species of the genera Dacrydium, Lepidothamnus, Nageia, Podocarpus, Prumnopitys and Saxegothaea are found beyond Australasia, in India, Japan, China, Africa, the Caribbean and the New World south from Mexico to Chile. Of these, Saxegothaea, a monotypic genus found in Chile and Argentina, is the only genus with no representatives in the Australasian region. Most members of the family are trees native to wet tropical or subtropical (often, tropical mountains) forests. A few are small trees or shrubs native to forest understory environments. Big TreeThe totara, Podocarpus totara. OldestDendrochronologyEthnobotanyObservationsRemarksAlthough the second-largest conifer family, the Podocarpaceae are far less well-known than the other two big families, Pinaceae and Cupressaceae. There are several possible reasons for this situation. The Podocarpaceae are chiefly a tropical family, thus few species have attracted interest among the European horticultural community and few species are known for their ornamental value. The family does not otherwise possess great economic importance -- only a few species are exploited for timber, and those are for the most part greatly diminished by overcutting -- so it has not attracted attention on that score. Most species in the family are found in tropical forests that are dominated by a great many species of angiosperm trees, so the family does not possess the ecological significance attached to Pinaceae or Cupressaceae. Finally, the family is primarily found in Third World countries, where plants in general receive little research unless they be economically important. This is a regrettable state of affairs, because the Podocarpaceae probably contain more species threatened by overcutting and habitat loss than any other family. In view of the above considerations, in seems inevitable that many taxa described here are bound for extinction in the coming decades. Netta E. Gray did much of the early work on Podocarpus and its segregates (Afrocarpus, Nageia, Prumnopitys, Retrophyllum, and Sundacarpus). She was accordingly honored by D.J. de Laubenfels, the current grand old man of the Podocarpaceae, with Podocarpus grayae de Laub. 1985. The September 1973 Plant Science Bulletin carried this brief biography of Mrs. Gray: Netta E. Gray worked and studied with John T. Buchholz at the University of Illinois, completing her Masters degree in Botany. She was particularly interested in the genus Podocarpus. The work she started with Buchholz and later carried on herself was a careful systematic treatment of each of the sections of Podocarpus. She was concerned with the systematic importance of anatomical details, and the geographical distribution and evolution of the genus. As a result of her diligent study of the group she became one of the world's authorities on this genus and had such visitors as R. Florin come to her door. She lived with her husband Professor Stephen W. Gray near Atlanta, Georgia and taught at Agnes Scott College in Decatur, Georgia. She continued an active interest in research and publication about the genus, Podocarpus, as well as the Gymnosperms as a whole, until her death on August 24, 1970. CitationsSee AlsoBuchholz, J.T. and N.E. Gray. 1947. A Fijian Armopyle. Journal of the Arnold Arboretum 28: 141-143. Buchholz, J.T. and N.E. Gray. 1948. A Taxonomic Revision of Podocarpus. I. The Sections of the Genus and their Subdivisions with Special Reference to Leaf Anatomy. Journal of the Arnold Arboretum 29: 46-63. Buchholz, J.T. and N.E. Gray. 1948. A Taxonomic Revision of Podocapus, II. The American Species of Podocarpus: Section Stachycarpus. Journal of the Arnold Arboretum 28: 64-76. Buchholz, J.T. and N.E. Gray. 1948. A Taxonomic Revision of Podocwpus. IV. The American Species of Section Eupodocarpus, Sub-Sections C and D. Journal of the Arnold Arboretum 28: 123-151. Buchholz, J. T. and N. E. Gray, 1957. Contributions to the Flora of Venezuela - IV. Podocarpaceae. Fieldiana Botany 28: 759-772. Gray, N.E. and J.T. Buchholz. 1948. A Taxonomic Revision of Podocarpus. III. The American Species of Podocarpus: Section Polypodiopsis. Journal of the Arnold Arboretum 29: 117-122. Gray, N.E. and J.T. Buchholz. 1951. A Taxonomic Revision of Podocarpus. V. The South Pacific Species of Podocarpus: Section Stachycarpus. VI. The South Pacific Species of Podocarpus: Section Sundacarpus. Journal of the Arnold Arboretum Vol. 32: 82-92. Gray, N.E. 1953. A Taxonomic Revision of Podocarpus. VII. The African Species of Podocarpus: Section Afrocarpus. Journal of the Arnold Arboretum 34: 67-76. Gray, N.E. 1953. A Taxonomic Revision of Podocarpus. VIII. The African Species of Section Eupodocarpus, Subsections A and E. Journal of the Arnold Arboretum 34: 163-175. Gray, N.E. 1955. A Taxonomic Revision of Podocarpus. IX. The South Pacific Species of Section Eupodocarpus, Subsection F. Journal of the Arnold Arboretum 36: 199-206. Gray, N.E. 1960. A Taxonomic Revision of Podocarpus. XII. Section Microcarpus. Journal of the Arnold Arboretum 41: 36-39. Gray, N.E. 1962. A Taxonomic Revision of Podocarpus. XIII. Section Polypodiopsis in the South Pacific. Journal of the Arnold Arboretum 43: 67-79. Gray, N.E. 1969. An Interpretation of Podocarpus in Time and Space. The Bulletin of Georgia Academy of Science 27: 144-147.
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