Halwaxiids and the early evolution of the lophotrochozoans.
نویسندگان
چکیده
Halkieriids and wiwaxiids are cosmopolitan sclerite-bearing metazoans from the Lower and Middle Cambrian. Although they have similar scleritomes, their phylogenetic position is contested. A new scleritomous fossil from the Burgess Shale has the prominent anterior shell of the halkieriids but also bears wiwaxiid-like sclerites. This new fossil defines the monophyletic halwaxiids and indicates that they have a key place in early lophotrochozoan history.
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عنوان ژورنال:
- Science
دوره 315 5816 شماره
صفحات -
تاریخ انتشار 2007