High Quality Content by WIKIPEDIA articles! Xenusion is a possible very primitive arthropod/onychophore known from two specimens found in glacial debris in Germany. They probably originated in the Kalmarsund Sandstone of Southern Sweden (Jaeger and Martinsson 1966) and are probably late Neoproterozoic. The specimens are not especially well preserved. The older specimen is 10 cm or so in length with a narrow, weakly segmented body. A depression runs up the bottom on all but the rearmost segments. There is a slightly bulbous tail, and each segment beyond that seems to have a single pair of tapering annulated legs similar to the modern onychophore, but without claws. Nine segments are present. There is a spine on each body bump and faint transverse parallel striations on the annulations on the legs. The legs of what is possibly the foremost segments are either missing or not preserved. The head is believed to be missing or is poorly preserved. If Xenusion is an arthropod/onychophore, it...

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