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During the rehabilitation process at the University of Puerto Rico Department of Marine Sciences Sea Turtle Rehabilitation Facility (STRF) of a stranded olive ridley turtle, Lepidochelys olivacea, found 3 km off the northwest coast of Puerto Rico between Aguadilla and Rincon on 30 August 1997, a blood sample was taken for a red blood cell count and other diagnostics. A Haemoproteus sp. was found (Fig. 1). The exact abundance of this organism could not be determined, but it appeared to be present in relatively low numbers. The protozoan was identified to genus and line drawings were made. However, additional blood samples were not taken due to the weak condition of the turtle. Routine diagnostic blood samples taken after rehabilitation were negative for the protozoan. The turtle was deemed succesfully rehabilitated after 162 days, and released on 06 February 1998, 60 km south of St. Croix, USVI Unfortunately, the original slides containing the protozoan were lost in the mail before they could be deposited in a museum. The macrogametocyte (n=3, all poorly stained) was sausage shaped with a finely granular cytoplasm. It extended approximately two-thirds the way around the host nucleus displacing the nucleus only slightly (NDR [nucleus displacement ratio] = 0.5-0.6).

Figure 1. Macrogametocyte of Haemoproteus sp. in erythrocyte (red blood cell) of an olive ridley turtle, Lepidochelys olivacea (Chelonia: Chelonidae), found 3 km off the northwest coast of Puerto Rico between Aguadilla and Rincon 30 August 1997. Scale bar = 5 micrometers.

The border of the parasite was well defined. The parasite contained a few small, clear, intracytoplasmic vacuoles. Larger vacuoles were not observed. The cytoplasm contained 11 to 15 medium-sized, diffusely scattered, dark brown pigment granules. The parasite was closely adhered to the host cell nucleus and occupied most of the space in the cell on one side. It was 17.2 μm long and 3.2 μm wide. The parasite nucleus (n=1, visible) was oblong, 2.2 μm long and 1.8 μm wide, and centrally located.

No infections with 2 macrogametocytes per erythrocyte were observed, but only a total of three infected cells were observed. No microgametocytes or developing macrogametocytes were found.

The genus Haemoproteus can be diagnosed because of its large, pigmented, halter-shaped (or sausage-shaped) macrogametocyte in the erythrocytes of hosts. It often partially or completely encircles and displaces the nucleus of mature erythrocytes (Fig. 1). The protozoan parasite described above has not previously been reported from sea turtles and probably represents a new species. However, we had too few specimens to justify description of a species.

Members of this genus are more commonly found in birds, but occasionally occur in reptiles. Most of the hosts have been terrestrial or freshwater; however, a few marine records exist (Work & Rameyer 1995). They usually cause little harm to their hosts, but debilitated hosts are sometimes killed. The extremely emaciated olive ridley turtle may have been affected by this parasite; however, the parasite appeared to have remained at relatively low numbers and did not appear to be taking advantage of any reduced immunity/ resistance of the host.

Protozoan parasites of sea turtles have received relatively little attention. Herbst & Jacobson (1995) noted amebiasis, Entamoeba invadens, in captive sea turtles; and Márquez (1990) an amoeba, Entamoeba sp., in the leatherback turtle, Dermochelys coriacea. Graczyk et al. (1997) found Crypto, Cryptosporidium sp. infections in green turtles, Chelonia mydas, in Hawaii and Mercer et al. (2012) found it in a loggerhead turtle stranded in the Northern Adriatic Sea. A coccidian, Caryospora cheloniae, caused considerable disease damage in cultured green turtles in the Cayman Islands (Rebell et al. 1975; Leibovitz et al. 1978), and in free-living green turtles in Australia (Gordan et al. 1993). Another coccidian, Eimeria caretta, has been described from the loggerhead turtle, Caretta caretta (Upton et al. 1990). Chauvier (1986) found a “hémocytozoaire” parasite in the hawksbill turtle, Eretmochelys imbricata, in Europe. This could possibly represent the same parasite that we found, or a closely related species. Eiras et al. (2000) found intererythrocytic inclusion bodies in the loggerhead turtle from Madeira, Portugal. These probably represented viral, or rickettsial damage, not a protozoan.

Acknowledgments. We thank the U.S. Department of Fish and Wildlife for supporting the STRF; Department of Natural and Environmental Resources of the Commonwealth of Puerto Rico for permit DNRA:97-EPE-28; Dr. Curtis A. Colleton, Caribe Veterinary Pathology Consulting Group, Las Piedras, for assistance with blood work; Peter Rocafort, for scanning the drawing; and volunteers for assistance.

CHAUVIER, G. 1986. Pathologie des reptiles. 5. Un hemcytozoaire parasite de la tortue marine, Eretmochelys imbricata (Linne, 1766). Revue Française d’Aquariologie Herpétologie 12: 123-124.

EIRAS, J.C., T. DELLINGER, A.J. DAVIS, G. COSTA & A.P. ALVES DE MATOS. 2000. Intererythrocytic inclusion bodies in the loggerhead sea turtle Caretta caretta from Madeira. Journal of the Marine Biological Association U.K. 80: 957-958.

GORDON, A.N., W.R. KELLY & R.J.G. LESTER. 1993. Epizootic mortality in free-living green turtles Chelonia mydas, due to coccidiosis. Journal of Wildlife Diseases 29: 490-494.

GRACZYK, T.C., G.H. BALAZ, T. WORK, A.A. AGUIRRE, D.M. ELLIS, S.K.K. MURAKAWA & R. MORRIS. 1997. Cryptosporidium sp. infections in green turtles, Chelonia mydas, as a potential source of marine waterborne oocysts in the Hawaiian Islands. Applied and Environmental Microbiology 63: 2925-2927.

HERBST, L.H. & E.R. JACOBSON. 1995. Diseases of marine turtles. In: K.A. Bjorndal (Ed.). Biology and Conservation of Sea Turtles. Revised Edition. Smithsonian Institution Press, Washington, D.C. pp. 593-596

LAINSON, R. & R.D. NAIFF. 1998. Haemoproteus (Apicomplexa: Haemoproteidae) of tortoises and turtles. Proceedings of the Royal Society B 265: 941-949.

LEIBOVITZ, L., G. REBELL & G.C. BOUCHER. 1978. Caryospora cheloniae sp. n.: a coccidial pathogen of mariculture- reared green sea turtles (Chelonia mydas mydas). Journal of Wildlife Diseases 14: 269-275.

MARCER, F., E. MARCHIORI, P. DANESI, L. POPPI, C. TESSARIN, C. ZANADELLO & M. PIETROBELLI. 2012. Parasitofauna of loggerhead sea turtles (Caretta caretta) stranded in Northern Adriatic Sea. Mappe Parassitologiche 18: 187.

REBELL, G., A. RYWLIN & G.F. ULRICK. 1975. Coccidiosis in the green turtle (Chelonia mydas) in mariculture. Proceedings of the World Mariculture Society 5: 197-204.

UPTON, S.J., D.K. ODELL & M.T. WALSH. 1990. Eimeria caretta sp. nov. (Apicomplexa: Eimeriidae) from the loggerhead sea turtle, Caretta caretta (Testudines). Canadian Journal of Zoology 68: 1268-1269.

WORK, T.M. & R.A. RAMEYER. 1995. Haemoproteus iwa n. sp. in great frigatebirds (Fregata minor [Gemlin]) from Hawaii: parasite morphology and prevalence. Journal of Parasitology 82: 489-491.