出典:Wikipedia
出典:『Wikipedia』 (2011/07/05 14:32 UTC 版)
Heloplax is a worm-like mollusc. Its soft parts are preserved in three dimensions in the Silurian Herefordshire lagerstatte; its disarticulated valves are known from other Silurian deposits. It is very bizarre by modern standards; it bears serially repeated units, and has spines. It probably falls somewhere between the aplacophorans and polyplacophora; its valves were composed of aragonite