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Broken fragments of Tipheophyllum bartrumi in a river-worn boulder of limestone
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Tipheophyllum bartrumi
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In the Devonian, rugose corals were at their peak, and they were responsible for large areas of reef-building in areas of warm and shallow seas. Over 170 species have been identified from this period, and although the Devonian rocks of New Zealand are generally species-poor, eight taxa have been recorded from the Reefton Formation and two from the Baton formations, including solitary, massive and branching forms. The reefs they built were important habitats, not just for corals but a range of other organisms, including stromatalids
One of these is Tipheophyllum bartrumi. This was a colonial rugose coral in which individual corallites grew in a fan-like structure, joined at the base. The resulting form was box-like in shape, and an important part of the reefs that were being built at the time. The image top right shows a mass of the species which is more-or-less intact. It might be imagined turned ca. 70 degree to the left, in an upright, growing position. It clearly shows the individual corallites, with their separate walls, and within those the septae are also clear. Both of these features confirm that the coral is rugose, and help to establish its identification (see the page Corals for clues on identification). Tipheophyllum bartrumi is probably the easiest coral to find and identify in the Devonian rocks of New Zealand. Most finds, however, are of broken fragments that appear to have tumbled from the reef during erosion - hence the 'smashed-up' appearance of the specimen above. Both specimens shown above derive from the Reefton Formation in a small tributary of the Inangahua River, but the coral is also found more sparsely in the Baton River Formation. As well as giving an indication of the environment at the time, it helps to fix the age of the rocks to the early Devonian. Further examples, all from Reefton, are shown in the gallery of specimens from the collection, below. |
Mass of Tipheophyllum bartrumi, more-or-less intact
Polished section of Tipheophyllum bartrumi
Further Reading: Fagerstrom, J.A. & Bradshaw, M.A. 2002 Early Devonian reefs at Reefton, New Zealand: guilds, origin and paleogeographic significance. Lethaia 35, 35-50. Hill, D. 1956 The Devonian corals of Reefton in: New Zealand. New Zealand Geological Survey Paleontological Bulletin 25, pp. 5–14. |