Polypodiophyta. The Gleicheniaceae are terrestrial ferns comprising about half a dozen genera and 120 species found mainly in tropical and subtropical regions. The sporophyte consists of long, creeping rhizomes with vining aerial leaves that fork pseudodichotomously due to periodic arrested growth of the main axis. The leaves may occasionally reach several meters in length and commonly form a tangled mass in open habitats. The rhizomes bear long, uniseriate hairs. The leaf axis and rhizome have a single central "c"-shaped vascular bundle. The pear-shaped, more or less sessile sporangia have up to 128 spores and are borne in naked, circular sori.
Each "thumbnail" image below is linked to a larger photograph.
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This photo shows three genera of Gleicheniaceae. Upper left: Sticheris owhyhensis, lower left: Diploterygium pinnatum (uluhe lau nui), right: Dicranopteris linearis (uluhe). Notice the branching pattern in the fronds of each. |
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Dicranopteris linearis, uluhe. Notice the pseudodichotomously branching frond. |
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Diplopterigium pinnatum. |