| Hederellid | ||||
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 Scanning electron microscope image of a hederelloid from the Devonian of Michigan (largest tube diameter is 0. The scanning electron microscope ( SEM) is a type of Electron microscope that images the sample surface by scanning it with a high-energy beam of Electrons 75 mm).
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| Scientific classification | ||||
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Hederellids are extinct colonial animals with calcitic tubular branching exoskeletons. Incertae sedis ( Latin for "of uncertain placement" abbreviated "inc In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. An exoskeleton is an external Skeleton that supports and protects an animal's body in contrast to the internal Endoskeleton of for example a Human. They range from the Silurian to the Permian and were most common in the Devonian period. The Silurian is a geologic period and system that extends from the end of the Ordovician period about 443 The Permian is a geologic period and system that extends from 299 The Devonian is a geologic period and system of the Paleozoic era spanning from to million years ago. They are more properly known as "hederelloids" because they were originally defined as a suborder by Bassler (1939). Although they have traditionally been considered bryozoans, they are clearly not because of their branching patterns, lack of an astogenetic gradient, and wide range in tube diameters (Wilson and Taylor, 2001). Bryozoans are tiny colonial Animals that generally build stony Skeletons of Calcium carbonate, superficially similar to Coral (although some Work continues on assessing the true affinities of hederelloids.
 Three hederelloid species on a Devonian rugose coral; the largest zooids are about 1. Corals are Marine organisms from the class Anthozoa and exist as small Sea anemone –like Polyps typically in colonies of many 0 mm wide. |
 Hederelloids encrusting a brachiopod from the Devonian of Ohio; the largest zooids are about 1. Brachiopods (from Latin brachium, arm + New Latin -poda, foot are a small phylum of Benthic Invertebrates Also 0 mm wide. |
References
Bassler, R. S. (1939) The Hederelloidea. A suborder of Paleozoic cyclostomatous Bryozoa. Proceedings of the United States National Museum, 87:25-91.
Wilson, M. A. and Taylor, P. D. (2001) “Pseudobryozoans” and the problem of encruster diversity in the Paleozoic. PaleoBios, 21 (supplement to no. 2):134-135.
Wilson, M. A. and Taylor, P. D. (2006) Predatory drillholes and partial mortality in Devonian colonial metazoans. Geology 34: 565-568.