title: Diatoms and Other Epibionts Associated with Olive Ridley (Lepidochelys olivacea) Sea Turtles from the Pacific Coast of Costa Rica.
abstract: Although the sea turtles have long been familiar and even iconic to marine biologists, many aspects of their ecology remain unaddressed. The present study is the first of the epizoic diatom community covering the olive ridley turtle's (Lepidochelys olivacea) carapace and the first describing diatoms living on sea turtles in general, with the primary objective of providing detailed information on turtle epibiotic associations. Samples of turtle carapace including the associated diatom biofilm and epizoic macro-fauna were collected from Ostional beach (9° 59´ 23.7´´ N 85° 41´ 52.6´´ W), Costa Rica, during the arribada event in October 2013. A complex diatom community was present in every sample. In total, 11 macro-faunal and 21 diatom taxa were recorded. Amongst diatoms, the most numerous were erect (Achnanthes spp., Tripterion spp.) and motile (Haslea sp., Navicula spp., Nitzschia spp., Proschkinia sp.) forms, followed by adnate Amphora spp., while the most common macro-faunal species was Stomatolepas elegans (Cirripedia). Diatom densities ranged from 8179 ± 750 to 27685 ± 4885 cells mm-2. Epizoic microalgae were either partly immersed or entirely encapsulated within an exopolymeric coat. The relatively low diatom species number, stable species composition and low inter-sample dissimilarities (14.4% on average) may indicate a mutualistic relationship between the epibiont and the basibiont. Dispersal of sea turtle diatoms is probably highly restricted and similar studies will help to understand both diatom diversity, evolution and biogeography, and sea turtle ecology and foraging strategies.
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, II University of Naples, Caserta, Italy.
authors.forename: Roksana
authors.initials: R
authors.lastname: Majewska
authors.affiliation: Department of Public Health and Infectious Diseases, Section of Parasitology, Sapienza University of Rome, Rome, Italy; Istituto Zooprofilattico Sperimentale del Mezzogiorno, Portici, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Santoro
authors.affiliation: Escuela de Biología, Universidad de Costa Rica, San José, Costa Rica.
authors.forename: Federico
authors.initials: F
authors.lastname: Bolaños
authors.affiliation: Escuela de Biología, Universidad de Costa Rica, San José, Costa Rica.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Chaves
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, II University of Naples, Caserta, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: De Stefano
mesh_terms: D033304:Amphipoda / Q000502:physiology*; D000818:Animals; D003364:Costa Rica; D017377:Diatoms / Q000502:physiology*; D008855:Microscopy, Electron, Scanning; D009425:Nesting Behavior / Q000502:physiology*; D010140:Pacific Ocean; D012623:Seawater; D014426:Turtles / Q000033:anatomy & histology / Q000502:physiology*