Janos Hennicke Javier Martinez Katrin Ludynia Roxana Torres Thierry M. Work Stedson Stroud Juan F. Masello Petra Quillfeldt Santiago Merino 2012 <p>Among seabirds, the fregatids stand out with a high prevalence of blood parasites. Four of 5 species in this family have been found to be infected with <i>Haemoproteus</i>; however, complete species descriptions with molecular phylogeny are lacking. Seventy-five samples from 4 species of frigatebirds, i.e., <i>Fregata andrewsi</i>, <i>Fregata minor</i>, <i>Fregata magnificens</i>, and <i>Fregata aquila</i>, were screened for infections caused by species of <i>Haemoproteus</i>. Four different parasite haplotypes were found infecting frigatebirds based on the sequencing of a fragment of the <i>cytochrome b</i> gene. Two haplotypes belong to the subgenus <i>Parahaemoproteus</i>, and the other 2 correspond to haplotypes within the subgenus <i>Haemoproteus</i>. The more prevalent and cosmopolitan <i>Parahaemoproteus</i> haplotype (FregPHae1) was phylogenetically grouped with other <i>Haemoproteus</i> parasites infecting non-passerine birds, but it could not be detected from the single sample from <i>F. aquila</i>. The other <i>Parahaemoproteus</i> haplotype (FregPHae2) was not phylogenetically clustered with parasites infecting non-passerine birds, and it was sequenced from a single (1 each) <i>F. andrewsi</i> and <i>F. minor</i>. Blood smears from <i>F. andrewsi</i> infected only by FregPHae1 haplotype showed sufficient gametocytes to allow description of a new species, <i>Haemoproteus valkiūnasi</i> sp. nov. In contrast to <i>Haemoproteus iwa</i>, the only previously known blood parasite infecting frigatebirds and described from F. minor from Galapagos Islands, parasites from <i>F. andrewsi</i> (1) are shorter with no contact of gametocyte with host cell membrane, (2) have fewer pigment granules, and (3) have wider microgametocytes, with a smaller host nuclear displacement. In contrast, patent single infections corresponding to the cosmopolitan haplotype of the subgenus <i>Haemoproteus</i> (FregHae1) were also found in samples from 1 <i>F. andrewsi</i>, 1 <i>F. minor</i>, and 1 <i>F. aquila</i>. In all these cases, the number of microgametocytes was very low, resembling <i>H. iwa</i>, which lacks microgametocytes in the original description. Macrogametocytes of haplotype FregHae1 in <i>F. andrewsi</i> differ significantly from all the characteristics measured from <i>H. valkiūnasi</i>. In addition, it also differs from all characteristics of <i>H. iwa</i> despite being genetically identical in the analyzed fragment.</p> application/pdf 10.1645/GE-2415.1 en American Society of Parasitologists Infection by Haemoproteus parasites in four species of frigatebirds and the description of a new species of Haemoproteus (Haemosporida: Haemoproteidae) article