Co-infection by alveolate parasites and frog virus 3-like ranavirus during an amphibian larval mortality event in Florida, USA.

A multispecies amphibian larval mortality event, primarily affecting American bullfrogs Lithobates catesbeianus, was investigated during April 2011 at the Mike Roess Gold Head Branch State Park, Clay County, Florida, USA. Freshly dead and moribund tadpoles had hemorrhagic lesions around the vent and on the ventral body surface, with some exhibiting a swollen abdomen. Bullfrogs (100%), southern leopard frogs L. sphenocephalus (33.3%), and gopher frogs L. capito (100%) were infected by alveolate parasites. The intensity of infection in bullfrog livers was high. Tadpoles were evaluated for frog virus 3 (FV3) by histology and PCR. For those southern leopard frog tadpoles (n = 2) whose livers had not been obscured by alveolate spore infection, neither a pathologic response nor intracytoplasmic inclusions typically associated with clinical infections of FV3-like ranavirus were noted. Sequencing of a portion (496 bp) of the viral major capsid protein gene confirmed FV3-like virus in bullfrogs (n = 1, plus n = 6 pooled) and southern leopard frogs (n = 1, plus n = 4 pooled). In July 2011, young-of-the-year bullfrog tadpoles (n = 7) were negative for alveolate parasites, but 1 gopher frog tadpole was positive. To our knowledge, this is the first confirmed mortality event for amphibians in Florida associated with FV3-like virus, but the extent to which the virus played a primary role is uncertain. Larval mortality was most likely caused by a combination of alveolate parasite infections, FV3-like ranavirus, and undetermined etiological factors.

Unraveling Siren (Caudata: Sirenidae) systematics and description of a small, seepage specialist.

For approximately four decades, scientists have known of the existence of several undescribed species of Siren in the southeastern United States Coastal Plain. One of these species, S. reticulata, was recently described, but a small, seepage-dwelling species has remained undescribed until now. To resolve outstanding questions concerning the phylogeny of Siren, we collected sequence and morphometric data from specimens across the range of Siren. We found S. lacertina and S. reticulata to represent strongly supported monophyletic groups, with S. reticulata having a sister relationship to all other Siren. Additionally, we found five distinct mtDNA lineages within what has been recognized as S. intermedia. Siren lacertina and type-locality S. intermedia (lineage A) are sister mtDNA lineages, whereas S. intermedia lineages B and C show a high level of mitogenomic divergence from type-locality S. intermedia. Analyses of two scnDNA loci revealed that S. lacertina is monophyletic but nested with low positional support in a clade including the three S. intermedia mtDNA lineages. Further study is needed to determine whether S. intermedia lineages A, B, and C represent distinct species or incompletely sorted lineages. We restrict the range of S. intermedia to the region from the Escambia and Perdido river drainages of Florida and Alabama eastward through Virginia (the combined ranges of lineages A, B, and C). We also elevate S. i. nettingi (lineage E) to species status and include the larger S. i. texana form in that taxon, generating a species that occurs from the Mobile Bay drainages westward through the Mississippi Basin and southwest into northeastern Mexico. Lastly, we describe a new miniature species, S. sphagnicola, that ranges from the Florida Parishes of Louisiana eastward to the westernmost tributary creeks of Choctawhatchee Bay in the western Florida panhandle.

Multisystemic Enterococcosis in Brown Anoles (Anolis sagrei) from Florida, USA.

Beginning in July 2019, numerous free-ranging brown anoles (Anolis sagrei), an invasive lizard species in Florida, USA, were reported with large, soft, subcutaneous masses and disfiguring facial swellings. Postmortem evaluations of six affected animals, including cytology, histology, and electron microscopy, identified the presence of myriad chain-forming coccoid bacteria surrounded by a prominent clear capsule and abundant lightly basophilic matrix material with minimal associated granulomatous inflammation and effacement of normal tissue. Standard PCR and sequencing of the lesions revealed 100% nucleotide identity to Enterococcus lacertideformus. This bacterium was first observed in 2014 as the cause of a severe, multisystemic infection in several species of lizards (geckos and skinks) on Christmas Island, an Australian external territory in the Indian Ocean. Previously, analysis of E. lacertideformus had been hindered by an inability to grow the bacterium in standard culture conditions. We successfully cultured the organism on primary anole kidney cells. Given the growing recognition of host species diversity and geographic distribution noted for this organism, there is potential concern for spread to native North American lizards, especially the green anole (Anolis carolinensis), whose population numbers have apparently decreased due to introduced brown anoles.