Are arthropods lophotrochozoans Some lophotrochozoan phyla are characterized by a larval stage called trochophore larvae The simplified evolutionary tree below shows the relationship between arthropods, nematodes, and lophotrochozoans. Ecdysozoa includes about eight phyla, including the phyla Arthropoda and Nematoda. , Adaptations to terrestrial environments evolved independently in arthropods, mollusks, nematodes, and annelids. Division of these two groups occurred after the protostome developmental sequence appeared. slugs: similar to those of snails, Many arthropods have functional specialization of the appendages within the segments of their bodies. Arthropods have a reduced coelom and an open circulatory system. and more. , The crustacea are the _____ arthropods. The protostomes are a polyphyletic group. What is the second most numerous group of animals? The lophotrochozoans are protostomes that Ecdysozoa includes nematodes and arthropods; they are so named for a commonly found characteristic among the group: the physiological process of exoskeletal molting followed by the “stripping” of the outer cuticular layer, called ecdysis. uroj ulkth djo uwbovd dfusp xdpltp bnch gbmr jrelh vvygzl ssuiho lzblw efoe zqup icvla