margaritatus, Hypancistrus Tan [M.] & Armbruster [J. W.] 2016:128, Figs. 3-4 [ZooKeys No. 552; ref. 34145] Takutu River ca. 2.75 km W of Saint Ignatius, Rio Branco, Rio Negro drainage, Amazon basin, Guyana, 3.35500°N, 59.83077°W. Holotype (unique): CSBD F1701/AUM 35610. Holotype for the time being in AUM, eventually to be transferred to CSBD. •Valid as Hypancistrus margaritatus Tan & Armbruster 2016. Current status: Valid as Hypancistrus margaritatus Tan & Armbruster 2016. Loricariidae: Hypostominae. Distribution: Takutu River, tributary of the Rio Branco, Rio Negro drainage, Amazon basin, Guyana. Habitat: freshwater.