| 释义 |
mach·ae·rid·ia
\ˌmakəˈridēə\ noun plural
Usage: capitalized
Etymology: New Latin, from Latin machaera sword, dagger (from Greek machaira) + New Latin -idia
: a small group of Ordovician and Devonian animal fossils that are wormlike and bilaterally symmetrical but enclosed by plates suggesting those of echinoderms, are considered structurally comparable to the dipleurula and ancestral to modern echinoderms, being then made a class of Echinodermata, or are regarded as aberrant barnacles and included among the Cirripedia |