John Zardus

Department of Biology, The Citadel

Address: 171 Moultrie St., Charleston, SC 29409
Phone: 843.953.7511


Ph.D., 1998, Northeastern University

Research Interests

  • Marine invertebrate zoology
  • Benthic ecology
  • Larval biology
  • Population genetics
  • Biology of commensal barnacles

Current and planned research projects

  • Phylogenetics of commensal barnacles
  • Settlement selection of turtle barnacles
  • Population genetics of epibionts
  • Kinematics of larval barnacle swimming


  • Boyd LL, Zardus JD, Knauer CM & Wood LD. 2021. Evidence for host selectivity and specialization by epizoic Chelonibia barnacles between hawksbill and green sea turtles. Frontiers in Ecology and Evolution 9:807237.
  • Chan BKK, Wong YH, Robinson NJ, Lin J-C, Yu S-P, Dreyer N, Cheng I-J, Høeg JT & Zardus JD. 2021. 500 million years to mobility: Directed locomotion and its ecological function in a turtle barnacle. Proceedings of the Royal Society of London Series B 288:20211620.
  • Dreyer N, Zardus JD, Høeg JT, Olesen JM, Yu M-C & Chan BKK. 2020. How dolphin barnacles attach to their hosts and the paradox of remarkably versatile attachment structures in cypris larvae. Organisms Diversity & Evolution 20:233-249.
  • Lane ZM, McElroy EJ, Kendrick MR & Zardus JD. 2021. Experimental demonstration of exclusively passive feeding in the sea-turtle barnacle Chelonibia testudinaria (Linnaeus, 1758) (Cirripedia: Coronulidae). Journal of Crustacean Biology 41:ruab053.
  • Robinson NJ, Lazo-Wasem E, Butler BO, Lazo-Wasem EA, Zardus JD & Pinou T. 2019. Spatial distribution of epibionts on olive ridley sea turtles at Playa Ostional, Costa Rica. PLoS ONE 14:e0218838.
  • Sloan K, Zardus JD & Jones ML. 2014. Substratum fidelity and early growth in Chelonibia testudinaria, a turtle barnacle especially common on debilitated loggerhead (Caretta caretta) sea turtles. Bulletin of Marine Science 90:581-597.
  • Zardus JD. 2021. A global synthesis of the correspondence between epizoic barnacles and their sea turtle hosts. Integrative Organismal Biology 3:obab002.
  • Zardus JD & Hadfield MG. 2004. Larval development and complemental males in Chelonibia testudinaria, a barnacle commensal with sea turtles. Journal of Crustacean Biology 24:409-421.
  • Zardus JD & Hadfield MG. 2005. Multiple origins and incursions of the Atlantic barnacle Chthamalus proteus in the Pacific. Molecular Ecology 14:3719-3733.
  • Zardus JD, Lake DT, Frick MG & Rawson PD. 2014. Deconstructing an assemblage of ‘turtle’ barnacles: species assignments and fickle fidelity in Chelonibia. Marine Biology 161:45-59.