This bears out a more general point that fossil taxa may appear plesiomorphic merely because they preserve only plesiomorphies, rather than the me ́lange of primitive and derived characters anticipated of organisms properly allocated to a position deep within animal phylogeny. We conclude that previous interpretations in which palaeoscolecids occupy a deeper position in the ecdysozoan tree lack particular morphological support and rely instead on a paucity of preserved characters. Considered within a formal cladistic context, these characters provide most overall support for a stem-priapulid affinity, meaning that palaeoscolecids are far-removed from the ecdysozoan ancestor. In a review of palaeoscolecid anatomy, including newly resolved details of the internal and external cuticle structure, we identify specific characters shared with various living nematoid and scalidophoran worms, but not with panarthropods. We report here a specimen of the horsehair worm (Gordiida, Nematomorpha) Spinochordodes bacescui (Cpue, 1965) found in a patient´s urine. Here, we consider the nature of the last common ancestor of living ecdysozoans through a detailed analysis of palaeoscolecids, an early and extinct group of introvert-bearing worms that have been proposed to be ancestral ecdysozoans. About 11 species occur in the United States. Capinera 2 Distribution This relatively small group of large worms is found throughout world, but usually is restricted to areas near water. Inferences based on living taxa can and should be tested against the fossil record, which provides an independent and direct view onto historical character combinations. common names: horsehair worms, hairworms, Gordian worms, nematomorphs scientific name: Gordius spp. Horsehair Worms, Hairworms, Gordian Worms, Nematomorphs, Gordius spp. Some species are parasitic on humans, but invertebrates and other vertebrates serve as hosts. 60 Likes, TikTok video from Rose Mari Solberg (rosemarisolberg): 'Nematomorpha (sometimes called Gordiacea, and commonly known as horsehair. The reconstruction of ancestors is a central aim of comparative anatomy and evolutionary developmental biology, not least in attempts to understand the relationship between developmental and organismal evolution. Whiles, in Freshwater Ecology (Second Edition), 2010 Phylum Nematomorpha Members of the Nematomorpha are known as horsehair worms or gordian worms (Fig.
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