Nathan K. Lujan

Nathan K. Lujan headshot

Nathan K. Lujan

Associate Curator of Fishes


B.Sc., Biology, Calvin College, 2000
Ph.D., Evolutionary Biology, Auburn University, 2009

Dr. Nathan K. Lujan is the Associate Curator of Fishes at the Royal Ontario Museum (ROM) and Assistant Professor in the Department of Ecology and Evolutionary Biology at the University of Toronto. Nathan is an internationally recognized expert on ecology and evolution of the Amazon basin, the most biodiverse freshwater ecosystem on Earth. Nathan's research is especially focused on clarifying the taxonomy, ecological diversity, and evolutionary history of the bizarre, highly diverse catfish suborder Loricarioidei, which includes many popular aquarium fishes and the only fishes known to primarily eat wood or parasitize and ingest the blood of larger fishes. Nathan has led over 20 biodiversity inventories of remote river basins of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela, and has discovered and described over 30 new fish species. Nathan’s expeditions are often transdisciplinary and conducted in collaboration with prominent contemporary artists, such as David Brooks and Mark Dion.

Nathan's research is motivated by the urgent need to catalog, conserve, and comprehend freshwater biodiversity in the face of pervasive environmental impacts to lakes, rivers, and streams. In Canada, he has collaborated with the Department of Fisheries and Oceans to map the genomic population structure of at-risk aquatic species, understand the effectiveness of Niagara Falls as a barrier to fish dispersal, and develop molecular tools for the early detection of invasive species.

Nathan has published over 50 peer-reviewed papers and book chapters, as well as New York Times editorials and popular articles. His research has been supported by the US National Science Foundation, the National Geographic Society, the Explorers Club, the American Museum of Natural History, and the Coypu Foundation.

Nathan's position was made possible with the generous support of the Herbert A. Fritch Family Foundation.      

Social Media Links

Instagram: @potamophile
Twitter: @DrNathanLujan

Other Links

Recent Scientific Publications

Complete list of publications and associated citation information available from Google Scholar Citations here


  1. Lehman A., P., N.K. Lujan, R.E. Reis. A new species of armored catfish (Loricariidae: Hypoptopomatinae) syntopic and superficially similar to Parotocinclus collinsae, from the Potaro River basin, Guyana. Ichthyology & Herpetology. In press.
  1. Cucalon, R.V., J. Valdiviezo-Rivera, P. Jiménez-Prado, R. Navarrete-Amaya, V.R. Shervette, A. Torres-Noboa, N. Wierzal, T. Borders, N.K. Lujan, W.E. Aguire. 2021. Phylogeography of the Chocó endemic rainbow characin (Teleostei: Rhoadsia). Ichthyology & Herpetology. In press.
  1. Henschel, E., R.E. Schmidt, M.J. Bernt, J.N. Baskin, N.K. Lujan. Osteology-focused redescription and description of two Guiana Shield candirus: Paracanthopoma parva and Xxxxx xxxx n.sp. (Trichomycteridae: Vandelliinae) Journal of Fish Biology. In press.
  1. Armbruster, J.W., N.K. Lujan. 2021. Identification of the loricariid catfish fossil Taubateia as a member of the Rhinelepinae. Journal of Paleontology. In press.
  1. Henschel, E., N.K. Lujan. 2021. Range extension of the miniature pencil-catfish Potamoglanis wapixana (Siluriformes: Trichomycteridae) into the Essequibo River basin, Guyana. Journal of Fish Biology. Early view.
  1. Faustino-Fuster, D.R., V. Meza-Vargas, N.R. Lovejoy, N.K. Lujan. 2021. Multi-locus phylogeny with dense Guiana Shield sampling supports new suprageneric classification of the Neotropical three-barbeled catfishes (Siluriformes: Heptapteridae). Molecular Phylogenetics and Evolution. 162:107186.
  1. Armbruster, J.W., N.K. Lujan, D.D. Bloom. 2021. Redescription of the Guiana Shield darter species Characidium crandellii and C. declivirostre (Crenuchidae) with descriptions of two new species. Ichthyology & Herpetology. 109:102–122.


  1. Henschel, E., N.K. Lujan, J.N. Baskin. 2020. Ammoglanis natgeorum, a new miniature pencil catfish (Siluriformes: Trichomycteridae) from the lower Atabapo River, Amazonas, Venezuela. Journal of Fish Biology 97:1481–1490.
  1. McCauley, M., D.P. German, N.K. Lujan, C.R. Jackson. 2020. Gut microbiomes of sympatric Amazonian wood-eating catfishes (Loricariidae) reflect host identity and little role in wood digestion. Ecology and Evolution 10:7117–7128.
  1. Bressman, N.R., J.W. Armbruster, N.K. Lujan, I. Udoh, M.A. Ashley-Ross. 2020. Evolutionary optimization of an anatomical suction cup: Lip collagen content and its correlation with flow and substrate in Neotropical suckermouth catfishes (Loricarioidei). Journal of Morphology 281:676–687.
  1. Lujan, N.K., J.T. Weir, B.P. Noonan, N.R. Lovejoy, N.E. Mandrak. 2020. Is Niagara Falls a barrier to gene flow in riverine fishes? A test using genome-wide SNP data from seven native species. Molecular Ecology 29:1235–1249.
  1. Ortega-Lara, A., N.K. Lujan. 2020. Panaque nigrolineatus laurafabianae, a new commercially exploited subspecies of wood-eating pleco (Loricariidae: Hypostominae) from the Guaviare River basin in Colombia. Zootaxa 4723:393–408.
  1. Lujan, N.K., J.W. Armbruster, D.C. Werneke, T.F. Teixeira, N.R. Lovejoy. 2020. Phylogeny and biogeography of the Brazilian-Guiana Shield armored catfish Corymbophanes clade (Loricariidae). Zoological Journal of the Linnean Society 188:1213–1235.


  1. Roxo, F.F., L.E. Ochoa, M.H. Sabaj, N.K. Lujan, R. Covain, G.S.C. Silva, J. Chang, M.E. Alfaro, J.S. Albert, B.F. Melo, C. Oliveira. 2019. Phylogenomic reappraisal of the suckermouth armored catfish family Loricariidae (Teleostei: Siluriformes) using ultraconserved elements. Molecular Phylogenetics and Evolution 135:148–165.
  1. Moody, E.K., N.K. Lujan, K.A. Roach, K.O. Winemiller. 2019. Threshold elemental ratios and the temperature dependence of herbivory in fishes. Functional Ecology 33:913–923.