Abstract
Abstract
Background
The genus
Caryospora
Léger, 1904 comprises facultatively heteroxenous coccidia that predominantly parasitize snakes, with seven nominal species recorded in vipers (Viperidae). In the Neotropical region, the Jararaca
Bothrops jararaca
(Wied-Neuwied, 1824) and the Common Lancehead
Bothrops atrox
(Linnaeus, 1758) were previously the only recorded viperid hosts for
Caryospora jararacae
(Carini, 1939). This study aimed to provide a morphological redescription and the first molecular characterization of
C. jararacae
, alongside a global taxonomic review of
Caryospora
spp. in viperids.
Methods
Fecal samples from
B. jararaca
and Cascabel Rattlesnakes
Crotalus durissus
Linnaeus, 1758 were analyzed for oocyst morphology. Molecular characterization of
C. jararacae
was performed using a multilocus approach combining three mitochondrial loci and the nuclear 18S rDNA gene. Additionally, an integrative review synthesizing global data on geographic distribution, host specificity, and genotypic similarities of viperid
Caryospora
spp. was conducted.
Results
Caryospora jararacae
was identified and redescribed from
B. jararaca
and
C. durissus
. By reidentifying previous morphometric reports from
C. durissus
as
C. jararacae
and providing the first genetically confirmed records for both host species, this study establishes
C. jararacae
as the sole
Caryospora
species known from Neotropical vipers and only the second genotypically characterized
Caryospora
species in the family Viperidae worldwide. The integrative review revealed that five of the seven nominal species reported in vipers belong to the
Caryospora simplex
species complex, representing five morphologically indistinguishable geotypes distributed across different continents.
Conclusions
Molecular evidence primarily supports a scenario of recent common ancestry and incipient speciation among geotypes of the
Caryospora simplex
species complex, wherein high genetic similarity reflects shared ancestral characters, rather than active ongoing genetic exchange. Despite their morphological indistinguishability, retention of the five nominal species within the complex is recommended, as they can be delimited through an integrative framework combining biogeographical, host, and molecular data.