Spengelidae is a family of worms belonging to the class Enteropneusta, order unknown. The larvae of one of its species, Schizocardium californicum, are known for not expressing Hox genes.
Genera: Glandiceps Spengel, 1891 Mazoglossus Bardack, 1997 Schizocardium Spengel, 1893 Spengelia Willey, 1898 Willeyia Punnett, 1903
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