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Record: oai:ARNO:532614

AuthorD.J. de Laubenfels
JournalFlora Malesiana - Series 1, Spermatophyta
AbstractMonoecious or dioecious trees and shrubs, some prostrate (and one parasitic on another member of the family, Parasitaxus, in New Caledonia). Each cotyledon, of which there are usually two but in a few cases more, a fused pair with a corresponding bifid tip. Foliage buds ranging from a loose cluster of reduced leaves to a complex specialized structure (in Podocarpus). Leaves of many shapes and sizes. Pollen produced in small cones with many microsporophylls, each of which have two inverted dorsal pollen sacs above which is a small sterile tip. Male cones may be solitary in the axils of ordinary leaves, sometimes many adjacent cone subtending leaves, or they may be terminal or clustered on special structures involving sterile scales, or in a few cases they may arise in the axils of scales at the base of a new foliage shoot. The pollen for all genera (except extra-Mal. Saxegothaea) is provided with two or more bladders or ‘wings’, a trait shared with many genera of Pinaceae. More than two are found only in Dacrycarpus (and extra-Mal. Microcarpus and Microcachrys). The basic seed producing structure in Podocarpaceae is a compound terminal or lateral cone in which fertile scales arise in the axils of cone bracts. The cone is further often subtended by a specialized shoot with scales or modified leaves or even a naked peduncle. The bract is usually a small scale but may be larger and in some cases hardly differs from foliage leaves. The fertile scale or epimatium is a highly modified shoot and in this family bears a single naked ovule on its upper surface. In one genus there is no scale while this and one other genus have erect ovules, but in the great majority of genera the ovule is inverted. The fertile scale cups the developing seed and may even completely surround it with only the micropyle protruding at the time of pollination. Fleshiness, either of the cone bracts or of the fertile scale (or both) is common and the whole female structure may be reduced to only one or a few fertile units and a few sterile units. This can yield plum-like fruits or, in other cases, structures resembling those of the cashew ( Anacardium occidentale).
Distribution. There is a strong Antarctic relationship with a broad extension into Malesia for the 172 known species in 13 genera (in Malesia 7 genera with 61 spp.). Of six local and generally primitive genera, four are in the Antarctic zone and two are in New Caledonia. Three wideranging genera extend also into the tropical American highlands and two of these further range across the tropical African highlands. All seven of the wide-ranging genera are common in Malesia, only one of which (Falcatifolium), however, is confined to the Asian tropics; five are in New Zealand. A few species reach into moist subtropical forests of eastern Asia.
Document typearticle
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