Janaspis is an extinct genus of osteostracan, that lived in the early Devonian period in Britain. It is characterised by a number of features of its armoured headshield, including the presence of raised rims around its eyes, the shape of its lateral and median fields (depressed areas of the headshield covered by small loose plates, which are common to most Osteostraci), its prominent dorsal spine, fairly long cornual processes (backwards pointing spines on each side of the headshield) and ornamentation. Janaspis was fairly small compared with other osteostracans, with a headshield measuring less than 60mm.[1]
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| Genus: | Janaspis
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| Janaspis pagei | |
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References edit
- ^ Joseph N. Keating, Robert S. Sansom and Mark A. Purnell (2012). "A new osteostracan fauna from the Devonian of the Welsh Borderlands and observations on the taxonomy and growth of Osteostraci" (PDF). Journal of Vertebrate Paleontology. 32 (5): 1002–1017. doi:10.1080/02724634.2012.693555. S2CID 32317622.
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