Definition of arrow worm in English:

arrow worm

noun

  • A slender transparent wormlike animal with fins, having spines on the head for grasping prey. It is common in marine plankton.

    Also called chaetognath

    Phylum Chaetognatha

    ‘Chaetognaths (commonly named arrow worms) are transparent marine metazoans, ranging in size from 2 to 120 mm.’
    • ‘As mentioned, the chaetognaths (‘arrow worms’) are clearly orthodox bilaterians.’
    • ‘Early Cambrian ‘protoconodonts’ are currently believed to be the unrelated remains of chaetognaths (or ‘arrow worms’).’
    • ‘Chaetognaths (‘arrow worms’) were considered to be deuterostomes until quite recently, when they were relocated to the protostomes.’
    • ‘Chaetognaths, commonly called arrow worms, were considered deuterostomes based on their tripartite coelom and the retention of the blastopore to form the anus.’