Cristina Cox Fernandes

B.S., University Gama Filho, 1982

Ms, Instituto Nacional de Pesquisas da Amazônia, 1989

Ph.D. Duke University, 1995

Research Interests: 

My research focuses on the taxonomy of Gymnotiformes, which are the electric fishes of the Neotropics. Recently with my colleagues I described two new species of electric knifefishes from the Amazon basin. The Amazon supports about 3000 fish species, with new species being discovered on a regular basis. The knifefishes in these papers navigate and communicate with each other using electrical signals. In these papers, we studied the anatomy and morphology of these fishes, which turn out to be distinct from other known species. In the last decades, I have worked more broadly on the ecology and evolutionary diversity of neotropical freshwater fishes. Much of my research aims to provide basic information about the Gymnotiformes (electric fishes). 

More information about my research at Cristina Cox Fernandes Ichthyology & Herpetology 113(1), 179-181 (10 April 2025).
More about the UMASS Fish Collection at Fish collection at UMASS

Representative Publications: 
Cox Fernandes, C., Keeffe, R. and Pinilla C. E. 2024. Microsternarchus schonmanni, a new
species of weakly electric fish (Gymnotiformes: Hypopomidae, Microsternarchini) from the
Mamoré-Guaporé River Basin, Brazil. Proceedings of the Academy of Natural Sciences of
Philadelphia 168(1): 237-249.

Pinilla C. E, Cox Fernandes, C. and Alves-Gomes, J. A. 2025. Microsternarchus javieri, a new
species of weakly electric fish (Gymnotiformes: Hypopomidae, Microsternarchini) from the Rio
Negro basin, Brazil. Acta Amazônica

Cox Fernandes, C., Smith, G. T., Podos, J., Nogueira, A., Inoue, L., Akama, A., Ho, W. & Alves
Gomes, J. A. 2010. Hormonal and behavioral correlates of morphological variation in an
Amazonian electric fish (Sternarchogiton nattereri: Apteronotidae). Hormones and Behavior 58:
660-668.

Fernandes, C. C., Podos J. & Lundberg, J. G. 2004. Amazonian Ecology: Tributaries Enhance the Diversity
of Electric Fishes. Science 305: 1960-1962.

Collaborators:
John G. Lundberg
John P. Sullivan
Carolina Escamilla Pinilla
Rachel M. Keeffe
José Alves-Gomes
M. Chaise Gilbert
Alberto Akama
R. Craig Albertson
Eric. J. Hilton
Andrew Williston
Adília Nogueira
Ricardo Campo-Da-Paz

Publications:

Pinilla C. E, Cox Fernandes, C. and Alves-Gomes, J. A. 2025. Microsternarchus javieri, a new species of weakly electric fish (Gymnotiformes: Hypopomidae, Microsternarchini) from the Rio Negro basin, Brazil. Acta Amazônica

Cox Fernandes, C., Keeffe, R. and Pinilla C. E. 2024. Microsternarchus schonmanni, a new species of weakly electric fish (Gymnotiformes: Hypopomidae, Microsternarchini) from the Mamoré-Guaporé River Basin, Brazil. Proceedings of the Academy of Natural Sciences of Philadelphia 168(1): 237-249.

Gilbert M. C, Alberto A., C. Cox Fernandes and R. C. Albertson. 2020. Rapid morphological change in multiple cichlid ecotypes following the damming of a major clearwater river in Brazil. Evolutionary Applications 13:2754-2771

Keeffe, R., E. J. Hilton, M. J. F. Thomé de Souza & C. Cox Fernandes. 2019. Cranial morphology and osteology of the sexually dimorphic electric fish, Compsaraia samueli Albert & Crampton (Apteronotidae, Gymnotiformes), with comparisons to C. compsa (Mago-Leccia). 2019. Zootaxa 4555 (1): 101–112 

Hilton, E. J. & C. Cox Fernandes. Identity of “Apteronotus” bonapartii (Castelnau, 1855), a sexually dimorphic South American knifefish (Gymnotiformes: Apteronotidae) from the Amazon, with notes on its cranial osteology. 2017. Proceedings of the Academy of Natural Sciences of Philadelphia 165: 1-17.

Cox Fernandes, C. & A. Williston. Redescription of Microsternarchus bilineatus (Fernandéz-Yépez, 1968) (Gymnotiformes: Hypopomidae, Microsternarchini), with the designation of a neotype. 2017. Proceedings of the Academy of Natural Sciences of Philadelphia 165: 65-75.

Cox Fernandes, C., Nogueira, A., A. Williston & Alves-Gomes, J. A. 2015. A new species of electric knifefish from the rio Negro, Amazon basin (Gymnotiformes: Hypopomidae, Microsternarchini). Proceedings of the Academy of Natural Sciences of Philadelphia 164: 213-227. 

Cox Fernandes, C., Nogueira, A. & Alves-Gomes, J. A. 2014.Procerusternarchus pixuna, a new genus and species of electric knifefish (Gymnotiformes: Hypopomidae, Microsternarchini) from rio Negro River, South America. Proceedings of the Academy of Natural Sciences of Philadelphia 163:95-118.

Sullivan, J. P., Zuanon, J. and Cox Fernandes, C. 2013. Two new species and a new subgenus of toothed Brachyhypopomus electric knifefishes (Gymnotiformes, Hypopomidae) from the central Amazon and considerations pertaining to the evolution of a monophasic electric organ discharge. Zookeys 237:1-34.

Lundberg, J. G., Cox Fernandes, C., Campus da Paz, R. and Sullivan J. P. 2013. Sternarchella calhamazon n. sp., the Amazon’s most abundant species of apteronotid electric fish, with a note on the taxonomic status of Sternarchus capanemae Steindachner, 1868 (Gymnotiformes, Apteronotidae) Proceedings of the Academy of Natural Sciences of Philadelphia 162:157-173.

Santana, C. D. & Cox Fernandes, C. 2012. A new species of sexually dimorphic electric knifefish from the Amazon basin, Brazil (Gymnotiformes: Apteronotidae). Copeia 2012 (2): 2 83-292.

Ho, W., Cox Fernandes, C., Alves Gomes, J. A. & Smith, G. T. 2010. Sex differences in the electrocommunication signals of the electric fish "Apteronotus" bonapartii. Ethology 116: 1050-1064.

Cox Fernandes, C., Smith, G. T., Podos, J., Nogueira, A., Inoue, L., Akama, A., Ho, W. & Alves Gomes, J. A. 2010. Hormonal and behavioral correlates of morphological variation in an Amazonian electric fish (Sternarchogiton nattereri: Apteronotidae). Hormones and Behavior 58: 660-668.

Cox Fernandes, C., Lundberg, J.G. & Sullivan, J. P. 2009 Oedemognathus exodon and Sternarchogiton nattereri (Apteronotidae, Gymnotiformes): the case for sexual dimorphism and conspecificity. Proceedings of the Academy of Natural Sciences of Philadelphia 158: 193-207.

Lundberg, J.G. & Cox Fernandes, C. 2007. A new species of South American ghost knifefish (Apteronotidae: Adontosternarchus) from the Amazon Basin. Proceedings of the Academy of Natural Sciences of Philadelphia 156: 27-37.

Hilton, E. J., Cox Fernandes, C., Sullivan J. P., Campos-da-Paz, R., & Lundberg, J. G.. 2007.  Redescription of Orthosternarchus tamandua (Boulenger, 1898) (Gymnotiformes, Apteronotidae), with reviews of its ecology, electric organ discharges, morphology, osteology, and phylogenetic affinities. Proceedings of the Academy of Natural Sciences of Philadelphia 156: 1-25.

Hilton, E. J. & Cox Fernandes, C. 2006. Sexual Dimorphism in Apteronotus bonapartii (Castelnau, 1855) (Gymnotiformes: Apteronotidae). Copeia 2006 (4): 826-833.

Py-Daniel, L. R. & Cox Fernandes, C.2005.  Dimorfismo sexual em Siluriformes e Gymnotiformes (Ostariophysi) da Amazônia. Acta Amazônica Vol. 35(1) 2005:97-110.

Buhrnheim, C. M.   & Cox Fernandes, C. 2004. História natural e comportamento reprodutivo de Aequidens pallidus e Crenicichla inpa. In: Historia Natural, ecologia e conservação de algumas especies de plantas e animais da Amazônia. R. Cintra (ed.), EDUA / INPA / FAPEAM, Manaus, Pp 157-166

Cox Fernandes, C. & Podos, J. 2004. Sobre a descarga do órgão elétrico do sarapó Apteronotus hasemani (Gymnotiformes: Apteronotidae). In: Historia Natural, ecologia e conservação de algumas especies de plantas e animais da Amazônia. R. Cintra (ed.), EDUA / INPA / FAPEAM, Manaus, Pp 147-155

Cox Fernandes, C. 2004.  Movimentos migratórios de peixes em um sistema de várzea. In: Historia Natural, ecologia e conservação de algumas especies de plantas e animais da Amazônia. R. Cintra (ed.), EDUA / INPA / FAPEAM, Manaus, Pp. 141-146

Fernandes, C.C., Podos J. & Lundberg, J. G. 2004. Amazonian Ecology: Tributaries Enhance the Diversity of Electric Fishes. Science 305: 1960-1962.

Buhrnheim, C. M. & Cox Fernandes, C. 2003. Structure of fish assemblages in Amazonian rain-forest streams: effects of habitats and locality. Copeia 2: 255-262.

Cox Fernandes, C; Lundberg, J. G. & Riginos, C. 2002. The largest of all electric-fish snouts: hypermorphic facial growth in male Apteronotus hasemani, and comments on the nominal species A. anas (Gymnotiformes: Apteronotidae). Copeia 1:52-61.

Buhrnheim, C. M. & Cox Fernandes, C. 2001. Seasonal variation of fish communities in Amazonian rain forest streams. Ichthyological Exploration of Freshwaters 12(1):65-78.

Cox Fernandes, C. 1999.  Detrended canonical correspondence analysis (DCCA) of the electric fish assemblages in the Amazon. Proceedings of the International Symposium of Biology of Tropical Fishes. Ed. A. L. Val and V. M. F. Almeida-Val. Chapter 3, INPA, Manaus.

Cox Fernandes, C. 1998. Sex-related morphological variation in two species of apteronotid fishes (Gymnotiformes) from the Amazon River basin. Copeia 3: 730-735.

Cox Fernandes, C. 1997. Lateral migrations of fishes in Amazon floodplains. Ecology of Freshwater Fish 6:36-44.

Lundberg, J. G., Cox Fernandes C., Albert J. S. & Garcia, M. 1996. Magosternarchus, a new genus with two new species of electric fishes (Gymnotiformes: Apteronotidae) from the Amazon River basin, South America. Copeia 3: 657-670.

Cox Fernandes, C. & Petry, P. 1991. A importância da várzea no ciclo de vida dos peixes migradores da Amazônia. Bases Científicas para Estratégias de Preservação e Desenvolvimento da Amazônia: Fatos e Perspectivas. Ed. A. Val, E. Figliulo and E. Feldberg. Chapter 12, INPA, Manaus.

Bittencourt, M. M. & Cox Fernandes, C. 1990. Pesca comercial na Amazônia Central: uma atividade sustentada por peixes migradores. Ciência Hoje Vol. 11(64): 20-24.

Cox Fernandes, C. & de Merona, B. 1988. Lateral migrations of fishes on a floodplain system in the Central Amazon (Careiro Island - lake Rei), Br. Preliminary analysis. Memoria de la Soc. Cien. Nat. La Salle. Suplemento 2, Vol. XLVII: 409-432.