Pinophyta

Cordaitales †

Taxonomy and naming

The division name Pinophyta conforms with the rules of the ICBN, which state (Art 16.1) that the names of higher taxa in plants (above the rank of family) are either based on the name of the type genus, in this case, Pinus (pines), or are descriptive. In the latter case the name for the conifers is Coniferae (Art 16 Ex 2), which is in widespread use as well. Older scientific names (no longer allowed) are Coniferophyta and Coniferales.

Related Topics:
ICBN - Taxa - Pine

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In an older, broader sense of the name, the conifers were often considered equivalent to the Gymnosperms, although this grouping is polyphyletic as it includes distinct, only distantly related plants like the cycads and ginkgos not in the Pinophyta, but excludes the Magnoliophyta (flowering plants), equally or perhaps more closely related.

Related Topics:
Gymnosperm - Polyphyletic - Cycad - Ginkgo - Magnoliophyta

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The division contains just one class of living plants, class Pinopsida. Subdivision of the conifers into two or more orders has been proposed from time to time. The most commonly seen in the past was a split into two orders, Taxales (Taxaceae only) and Pinales (the rest), but recent genetic evidence has shown that this interpretation leaves the Pinales without Taxales as polyphyletic, and the latter order is no longer regarded as distinct. A more accurate division would be to split the division into three orders, Pinales containing only Pinaceae, Araucariales containing Araucariaceae and Podocarpaceae, and Cupressales (including Taxales) containing the remaining families, but there has not been any significant support for any division, with the majority of opinion preferring retention of all the families within a single order Pinales, despite their antiquity and diverse morphology.

Related Topics:
Taxales - Pinales - Polyphyletic

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The conifers are now accepted as comprising six to eight families, with a total of 65-70 genera and 600-650 species. The seven most distinct families are linked in the box above right and phylogenetic diagram left. In other interpretations, the Cephalotaxaceae may be better included within the Taxaceae, and some authors additionally recognise Phyllocladaceae as distinct from Podocarpaceae (in which it is included here). A further family Taxodiaceae was widely recognised in the past, but is now normally included within Cupressaceae.

Related Topics:
Phyllocladaceae - Taxodiaceae

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The conifers are an ancient group, with a fossil record extending back about 300 million years to the Paleozoic in the late Carboniferous period; even many of the modern genera are recognisable from fossils 60-120 million years old. Other classes and orders, now long extinct, also occur as fossils, particularly from the late Paleozoic and Mesozoic eras. Fossil conifers included many diverse forms, the most dramatically distinct from modern conifers being some herbaceous conifers with no woody stems. Major fossil orders of conifers or conifer-like plants include the Cordaitales, Vojnovskyales, Voltziales and perhaps also the Czekanowskiales (possibly more closely related to the Ginkgophyta).

Related Topics:
Fossil - Paleozoic - Carboniferous - Mesozoic - Herb - Cordaitales - Vojnovskyales - Voltziales - Czekanowskiales - Ginkgophyta

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