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Which four fish orders belong to the series Otophysi?
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ostariophysan
Knifefish, or featherback (Xenomystus nigri)
The series Otophysi consists of four fish orders, all of which are characterized by the presence of a true Weberian apparatusβa specialized bony connection between the swim bladder and the inner ear that enhances sound perception.1
The four orders belonging to the series Otophysi are:
- Characiformes (including characins, piranhas, and hatchetfishes)12
- Gymnotiformes (including electric eels and other knifefishes)12
- Cypriniformes (including minnows, carps, and suckers)12
- Siluriformes (the catfishes)12