50256 Ancistrus gymnorhynchus Kner, 1854 Loricariidae Armored catfishes Hypostominae Siluriformes Teleostei South America: Upper Pao River basin in the Orinoco River drainage and along coastal rivers of Carabobo and Yaracuy States, Venezuela. AMNH 18864 Xenocara gymnorhynchus AMNH 9625 1929 Xenocara gymnorhynchus AMNH 55005 1979 Xenocara gymnorhynchus