Staff Profile

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Caleb McMahan

Collections Manager, Fishes

Gantz Family Collections Center
Evolutionary Biology

Caleb is an integrative tropical biologist interested in the evolution, ecology, and distributions of fishes. While most of his work centers around the systematics, taxonomy, and historical biogeography of fishes, he collaborates with scientists active in areas of study such as paleontology, physiology, genomics, environmental science, and behavior. These interdisciplinary approaches offer the most toward enhancing our understanding of biodiversity. He works primarily with Neotropical freshwater fishes of Mexico, Central and South America.

For more information on Caleb's research program and joining the lab, visit Caleb's research website.

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Additional Information


Ph.D., Louisiana State University

M.S., Southeastern Louisiana University

B.S., Erskine College



Google Scholar Profile

33. Gomez-Gonzalez, A.E., Alvarez, F., Matamoros, W.A., Velazquez-Velazquez, E., Schmitter-Soto, J.J., Gonzalez-Diaz, A., & McMahan, C.D. 2018. Redescription of Vieja hartwegi (Taylor & Miller 1980) (Teleotei: Cichlidae) from the Grijalva River basin, Mexico and Guatemala, with the description of a rheophilic morph. Zootaxa 4375(3): 371-391.

32. Elías, D.J., Mochel, S.F., Chakrabarty, P., & McMahan, C.D. 2018. First Record of the Non-native Pacu, Piaractus brachypomus, in Lago Petén-Itzá, Guatemala, Central America. Occasional Papers of the Museum of Natural Science Louisiana State University 88: 1-6.

31. Díaz-Murillo, B.P., Ruiz-Campos, G., Piller, K.R., McMahan, C.D., García-De-León, F.J., & F. Camarena-Rosales. 2017. Assessing population-level morphometric variation of the Mountain Mullet Agonostomus monticola (Teleostei: Mugilidae) across its Middle American distribution. Neotropical Ichthyology 15(4): e170036.

30. Chakrabarty, P., Faircloth, B.C., Alda, F., Ludt, W.B., McMahan, C.D., Near, T.J., Dornburg, A., Albert, J.S., Arroyave, J., Stiassny, M.L.J., Sorenson, L., & M.E. Alfaro. 2017. Phylogenomic Systematics of Ostariophysan Fishes: Ultraconserved Elements Support the Surprising Non-Monophyly of Characiformes. Systematic Biology 66(6): 881-895.

29. Merchant, M., McAdon, C., Mead, S., McFatter, J., McMahan, C.D., Griffith, R., & Christopher M. Murray. 2017. Comparison of Serum Phospholipase A2 Activities of all Known Extant Crocodylian Species. Advances in Biological Chemistry 7(4): 151.

28. Bagley, J.C., Matamoros, W.A., McMahan, C.D., Tobler, M., Chakrabarty, P., & J.B. Johnson. 2017. Phylogeography and phyloeny of the convict cichlids (Cichlidae: Amatitlania): implications for species limits and Plio-Pleistocene evolutionary history in Central America. Biological Journal of the Linnean Society 120(1): 155-170.

27. McMahan, C.D., Ginger, L., Cage, M., David, K.T., Chakrabarty, P., Johnston, M., & W.A. Matamoros. 2017. Pleistocene to Holocene expansion of the black-belt cichlid in Central America, Vieja maculicauda (Teleostei: Cichlidae). PLoS ONE 12(5): e0178439.

26. McMahan, C.D., Kutz, J., Murray, C.M., Chakrabarty, P., Geheber, A.D., & D. Elias. 2017. Objectively measuring subjectively described traits: geographic variation in body shape and caudal coloration pattern within Vieja melanura (Teleostei: Cichlidae). Revista de Biología Tropical 65(2): 623-631.

25. Weller, H.I, McMahan, C.D., & M.W. Westneat. 2017. Dirt-sifting devilfish: winnowing in the geophagine cichlid Satanoperca daemon and evolutionary implications. Zoomorphology 136: 45-59.

24. Ceríaco, L.M.P., Gutiérrez, E.E., Dubois, A., ...McMahan, C.D., et al. 2016. Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological species. Zootaxa 4196(3): 435-445.

23. Murray, C.M., McMahan, C.D., Guyer, C., & B.I. Crother. 2016. The inhibition of scientific progress: perceptions of biological units. In: Assumptions Inhibiting Progress in Comparative Biology, Crother, B.I. & L.R. Parenti, Eds. CRC Press.

22. Jampangapé, J.A., Velázquez-Velázquez, E., Martínez-Ramirez, E., Anzueto-Calvo, M.J., Gomez, E.I., Dominguez-Cisneros, S.E., McMahan, C.D., & W.A. Matamoros. 2016. Validity and Redescription of Profundulus balsanus Ahl, 1935 (Cyprinodontiformes: Profundulidae). Zootaxa 4173(1): 55-65.

21. Matamoros, W.A., McMahan, C.D., Mejia, C.R., House, P.H., Armbruster, J.W., & P. Chakrabarty. 2016. First record of the non-native suckermouth armored catfish Hypostomus cf. niceforoi (Fowler 1943) (Siluriformes: Loricariidae) from Central America. Occasional Papers of the LSU Museum of Natural Science 87: 1-12.

20. McMahan, C.D., Freeborn, L.R., Wheeler, W.C., & B.I. Crother. 2015. Forked tongues revisited: molecular apomorphies support morphological hypotheses of squamate evolution. Copeia 103(3): 525-529.

19. McMahan, C.D. and S. Mochel. 2015. Clarification of type specimens for Bornean species of Osteochilus (Cyprinidae). Zootaxa 4032(1): 147-150.

18. McMahan, C.D., Matamoros, W.A., Piller, K.R., & P. Chakrabarty. 2015. Taxonomy and systematics of the hericthyins (Cichlidae: Tribe Heroini), with the description of eight new Middle American Genera. Zootaxa 3999(2): 211-234.

17. Matamoros, W.A., McMahan, C.D., Chakrabarty, P., Albert, J., & Schaefer, J. 2015. Derivation of the freshwater fish fauna of Central America Revisited: Myers’s hypothesis in the 21st Century. Cladistics 31(2): 177-188.

16. McMahan, C.D., Matamoros, W.A., Barraza, E., Kutz, J., & P. Chakrabarty. 2014. Taxonomic status of the Lago Coatepeque endemic convict cichlid Amatitlania coatepeque (Teleostei: Cichlidae). Copeia 4: 633-638.

15. Murray, C.M., McMahan, C.D., Dobie, J.L., Guyer, C. 2014. Cranial variation amongst independent lineages of the alligator snapping turtle (Macrochelys temminckii). Journal of Zoological Systematics & Evolutionary Research 52(4): 305-311.

14. Bohn, S., Barraza, E., McMahan, C.D., Matamoros, W., & B. Kreiser. 2013. Cross amplification of microsatellite loci developed for alligator gar (Atractosteus spatula) in tropical gar (Atractosteus tropicus). Revista Mexicana de Biodiversidad 84: 1349-1351.

13. McMahan, C.D., Smith, W.L., Sparks, J.S., Chakrabarty, P., & M.P. Davis. 2013. Temporal patterns of diversification across global cichlid biodiversity (Acanthomorpha: Cichlidae). PLoS ONE 8(8): e71162.

12. Carstens, B.C., Brennan, R.S., Chua, V., Duffie, C.V., Harvey, M.G., Koch, R.A., McMahan, C.D., Nelson, B.J., Newman, C.E., Satler, J.D., Seeholzer, G., Posbic, K., Tank, D.C., & J. Sullivan. 2013. Model selection as a tool for phylogeographic inference: An example from the willow Salix melanopsis. Molecular Ecology 22(15): 4014-4028.

11. Matamoros, W.A., Chakrabarty, P., Angulo, A., Garita-Alvarado, C.A., & C.D. McMahan.  2013.  A new species of Roeboides (Teleostei: Characidae) from Costa Rica and Panama, with a key to Middle American species of the genus. Neotropical Ichthyology 11(2): 285-290.

10. McMahan, C.D., Matamoros, W.A., Alvarez Calderon, F.S., HenrÍquez, W.Y., Recinos, H.M., Chakrabarty, P., Barraza, E., & N. Herrera. 2013. Checklist of the inland fishes of El Salvador. Zootaxa 3608(6): 440-456.

9. McMahan, C.D., Davis, M.P., DomÍnguez-DomÍnguez, O., GarcÍa de Leon, F.J., Doadrio, I., & K.R. Piller. 2013. From the mountains to the sea: phylogeography and cryptic diversity in the mountain mullet, Agonostomus monticola (Teleostei: Mugilidae). Journal of Biogeography 40: 894-904.

8. McMahan, C.D., Murray, C.M., Geheber, A.D., Boeckman, C.D., & K.R. Piller. 2011. Paraneetroplus synspilus is a junior synonym of Paraneetroplus melanurus (Teleostei: Cichlidae). Zootaxa 2833: 1-14.

7. Eckstut, M.E., McMahan, C.D., Crother, B.I., Ancheta, J., McLennan, D., & D. Brooks. 2011. PACT in Practice: Comparative historical biogeographic patterns and species area relationships of the Greater Antillean and Hawaiian Island terrestrial biotas. Global Ecology and Biogeography 20: 545-557.

6. McMahan, C.D., Geheber, A.D., & K.R. Piller. 2010. Molecular Systematics of the Enigmatic Middle American Genus Vieja (Teleostei: Cichlidae). Molecular Phylogenetics & Evolution 57: 1293-1300.

5. Rheubert, J.L., McMahan, C.D., Sever, D.M., Bundy, M.R., & K.M. Gribbins. 2010. Ultrastructure of the reproductive system of the Black Swamp Snake (Seminatrix pygaea) VII. Spermatozoon morphology and potential evolutionary trends of sperm characters among Serpentes. Journal of Zoological Systematics & Evolutionary Research 48(4): 366-375.

4. Geheber, A.D., McMahan, C.D., & K.R. Piller. 2010. First Record of the Non-native Three Spot Gourami (Osphronemidae: Trichogaster trichopterus) in Jamaica. Aquatic Invasions Supl. 1: S13-S16.

3. Kenway-Lynch, C.S., McMahan, C.D., Geheber, A.D., Hayes, M.M, & K.R. Piller. 2010. Threatened Fishes of the World: “Xenotoca” eiseni 1896 (Goodeidae). Environmental Biology of Fishes 87(3): 219-220.

2. Broach, J.S. & C.D. McMahan. 2009. New Records of Amphibians and Reptiles from Florence County, South Carolina, USA. Herpetological Review 40(2): 243-244.

1. McMahan, C.D. & G.R. Zug. 2007. Burmese Hemidactylus (Reptilia: Squamata: Gekkonidae): Geographic Variation in the Morphology of Hemidactylus bowringii in Myanmar and Yunnan, China. Proceedings of the California Academy of Sciences 58(24): 485-509.

Book Reviews & Other Publications:

4. Mohammadi, S. & C.D. McMahan. 2013. A Review of: Venomous Reptiles of the United States, Canada, and Northern Mexico Volume 2: Crotalus. Copeia 2013(1).

3. McMahan, C.D. 2012. Museum Techniques: Preservation of snake specimens for scientific study. Snake Species of the World, Encyclopedia of Life, Life Desks.

2. Edwards, M.L., & C.D. McMahan. 2011. Stuffed birds and pickled frogs:  the importance of natural history museums in South Carolina. South Carolina Wildlife.

1. McMahan, C.D. 2011. A Review of: A Field Guide to Coastal Fishes from Maine to Texas. Copeia 2011(3).


Professional affiliations

American Society of Ichthyologists and Herpetologists, Society for Systematic Biologists, Southeastern Fishes Council, Sociedad de Ictiología Mexicana, Neotropical Biogeography Network