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Title: A new species of the Ordovician horseshoe crab Lunataspis
Abstract Horseshoe crabs as a group are renowned for their morphological conservatism punctuated by marked shifts in morphology associated with the occupation of non-marine environments and have been suggested to exhibit a consistent developmental trajectory throughout their evolutionary history. Here, we report a new species of horseshoe crab from the Ordovician (Late Sandbian) of Kingston, Ontario, Canada, from juvenile and adult material. This new species provides critical insight into the ontogeny and morphology of the earliest horseshoe crabs, indicating that at least some Palaeozoic forms had freely articulating tergites anterior to the fused thoracetron and an opisthosoma comprising 13 segments.  more » « less
Award ID(s):
1943082
NSF-PAR ID:
10406035
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Geological Magazine
Volume:
160
Issue:
1
ISSN:
0016-7568
Page Range / eLocation ID:
167 to 171
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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