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Banffia is a genus of animals described from Early Cambrian fossils. The genus was named after Banff, Alberta, near where the first fossil specimens were discovered. Its placement in higher taxa is controversial. Banffia constricta is known from hundreds of fossils found in the Burgess shales. It is up to 10 cm in length, and divided equally into anterior and posterior parts. The entire body is twisted in a clockwise spiral, as seen from the front. This is believed to be a secondary adaptation from an initial bilateral condition. The anterior section is covered by two carapace-like un-mineralized shells that are fused together. A crown-like structure formed of three concentrate circular features surrounds the mouth. An antenna-form structure just posterior to the mouth may be a sensory organ. The posterior section is composed of 40 to 50 segments. The gut is straight, and the anus is at the terminal tip of the posterior section. The gut appears to have a series of diverticula or pouches. A possible circulatory system is visible in the fossils. B. constricta and B. constricta were probably filter or deposit feeders. The species Banffia confusa, known from fossils from the Chengjiang shales, was originally assigned to this genus, though, recent research shows that this species is not closely related to B. constricta, having been renamed as its junior synonym, Heteromorphus longicaudatus. ClassificationThere is no agreement on the classification of Banffia. Banffia constricta was assigned to the annelids by Walcott in 1911. As of 2006, different proposals would place Banffia in Urochordata, Vetulicolia or Arthropoda. While the body plan (equal anterior and posterior sections with segmentation) resembles that of the Vetulicolians, it is argued that the absence of gills and an endostyle, and the presence of gut diverticula makes Banffia unlikely to be a member of the deuterostomes. References
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