Merostomoidea
Encyclopedia
Merostomoidea is a paraphyletic
group of fossil arthropods. They have been described as a transitional form between trilobites and true chelicerates
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Paraphyly
A group of taxa is said to be paraphyletic if the group consists of all the descendants of a hypothetical closest common ancestor minus one or more monophyletic groups of descendants...
group of fossil arthropods. They have been described as a transitional form between trilobites and true chelicerates
Chelicerata
The subphylum Chelicerata constitutes one of the major subdivisions of the phylum Arthropoda, and includes horseshoe crabs, scorpions, spiders and mites...
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