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1.
Syst Parasitol ; 94(1): 65-72, 2017 01.
Article in English | MEDLINE | ID: mdl-28062992

ABSTRACT

Based on both unique morphological characteristics of the gamont, distinct changes caused to the host erythrocyte and analysis of partial 18S rRNA gene sequences, a new parasite of the genus Hepatozoon Miller, 1908 is described from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil. The new species, Hepatozoon musa n. sp., is characterized by large and curved mature gamonts (18.9 ± 0.9 µm in length and 3.8 ± 0.3 µm in width) that considerably engorge infected host erythrocytes and displace the nucleus laterally, which become longer and thinner. Phylogenetic estimates indicate the new species is more closely related to the recently described Hepatozoon cuestensis O'Dwyer, Moço, Paduan, Spenassatto, Silva & Ribolla, 2013, from Brazilian rattlesnakes. These recent findings highlight the need for further studies of Hepatozoon to better determine the biodiversity of this common but poorly-studied parasite group.


Subject(s)
Eucoccidiida/classification , Phylogeny , Animals , Brazil , Colubridae/parasitology , Eucoccidiida/cytology , Species Specificity
2.
Genesis ; 54(5): 257-71, 2016 05.
Article in English | MEDLINE | ID: mdl-26953634

ABSTRACT

Direct development in amphibians is characterized by the loss of aquatic breeding. The anuran Adelophryne maranguapensis is one example of a species with direct development, and it is endemic to the state of Ceará, Brazil. Detailed morphological features of A. maranguapensis embryos and the stages of sequential development have not been described before. Here, we analyzed all available genetic sequence tags in A. maranguapensis (tyr exon 1, pomc and rag1) and compared them with sequences from other species of Adelophryne frogs. We describe the A. maranguapensis reproductive tract and embryonic body development, with a focus on the limbs, tail, ciliated cells of the skin, and the egg tooth, which were analyzed using scanning electron microscopy. Histological analyses revealed ovaries containing oocytes surrounded by follicular cells, displaying large nuclei with nucleoli inside. Early in development, the body is unpigmented, and the neural tube forms dorsally to the yolk vesicle, typical of a direct-developing frog embryo. The hindlimbs develop earlier than the forelimbs. Ciliated cells are abundant during the early stages of skin development and are less common during later stages. The egg tooth appears in the later stages and develops as a keratinized microridge structure. The developmental profile of A. maranguapensis presented here will contribute to our understanding of the direct-development model and may help preserve this endangered native Brazilian frog. genesis 54:257-271, 2016. © 2016 Wiley Periodicals, Inc.


Subject(s)
Anura/growth & development , Embryonic Development , Extremities/growth & development , Skin/growth & development , Animals , Anura/genetics , Embryo, Nonmammalian , Oocytes/growth & development , Oocytes/metabolism , Skin/metabolism
3.
J Proteomics ; 114: 93-114, 2015 Jan 30.
Article in English | MEDLINE | ID: mdl-25462430

ABSTRACT

The Caatinga lancehead, Bothrops erythromelas, is a medically relevant species, responsible for most of the snakebite accidents in most parts of its distribution range in northeastern Brazil. The spectrum and geographic variability of its venom toxins were investigated applying a venomics approach to venom pools from five geographic areas within the Caatinga ecoregion. Despite its wide habitat, populations of B. erythromelas from Ceará, Pernambuco, Juazeiro, Paraiba, and Ilha de Itaparica exhibit highly conserved venom proteomes. Mirroring their compositional conservation, the five geographic venom pools also showed qualitatively and quantitatively overlapping antivenomic profiles against antivenoms generated in Vital Brazil (BR) and Clodomiro Picado (CR) Institutes, using different venoms in the immunization mixtures. The paraspecificity exhibited by the Brazilian SAB and the Costa Rican BCL antivenoms against venom toxins from B. erythromelas indicates large immunoreactive epitope conservation across genus Bothrops during the last ~14 million years, thus offering promise for the possibility of generating a broad-spectrum bothropic antivenom. Biological Significance Accidental snakebite envenomings represent an important public health hazard in Brazil. Ninety per cent of the yearly estimated 20-30,000 snakebite accidents are caused by species of the Bothrops genus. Bothrops erythromelas, a small, moderately stocky terrestrial venomous snake, is responsible for most of the snakebite accidents in its broad distribution range in the Caatinga, a large ecoregion in northeastern Brazil. To gain a deeper insight into the spectrum of medically important toxins present in the venom of the Caatinga lancehead, we applied a venomics approach to define the proteome and geographic variability of adult B. erythromelas venoms from five geographic regions. Although intraspecific compositional variation between venoms among specimens from different geographic regions has long been appreciated by herpetologists and toxinologists as a general feature of highly adaptable and widely distributed snake species, the five B. erythromelas populations investigated exhibit highly conserved venom proteomes. The overall toxin profile of the Caatinga lancehead's venom explains the local and systemic effects observed in envenomations by B. erythromelas. The five geographic venom pools sampled also showed qualitatively and quantitatively overlapping antivenomic profiles against antivenoms generated using different bothropic venoms in the immunization mixtures. The large immunoreactive epitope conservation across genus Bothrops offers promise for the generation of a broad-spectrum bothropic antivenom.


Subject(s)
Antivenins/metabolism , Bothrops/metabolism , Crotalid Venoms/metabolism , Proteomics/methods , Amino Acid Sequence , Animals , Antivenins/analysis , Bothrops/classification , Brazil , Chromatography, High Pressure Liquid , Crotalid Venoms/analysis , Crotalid Venoms/immunology , Ecosystem , Electrophoresis, Gel, Two-Dimensional , Peptide Fragments/analysis , Proteome/analysis , Species Specificity
4.
An Acad Bras Cienc ; 86(3): 1263-72, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25119731

ABSTRACT

The reproductive ecology of Ameivula ocellifera was studied from September 2009 to August 2010 in a coastal area of the state of Ceará, Brazil. Females reproduced continuously throughout the year, with a peak at the end of the rainy season. Even though there was a predominance of pre-reproductive individuals in the sample, gonadal activity of males peaked synchronously to female reproduction. Mean clutch size was 1.98 ± 0.56 and positively associated with female body size, while mean egg volume was 510.54 ± 84.29 mm3 and unrelated to female body size. We did not find any association between clutch size and average egg volume.


Subject(s)
Lizards/physiology , Animals , Brazil , Female , Lizards/classification , Male , Reproduction/physiology , Seasons , Sexual Maturation/physiology
5.
Pap. avulsos zool ; 53(8): 99-113, 2013.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1486816

ABSTRACT

We studied a snake assemblage from an area of Caatinga with shrub and tree vegetation to describe the natural history of the snake species. A total of 636 individuals among 22 species from four families were recorded. The distribution of species abundances is log-normal; and the composition presents typical species from the Caatinga, with Oxybelis aeneus (Wagler, 1824) and Philodryas nattereri Steindachner, 1870 being the most common. The natural history of each species is described based on information regarding activity patterns, diet, habitat use, reproduction, and defensive repertoire obtained during the study, as well as on information available in the literature. The study area is located in a priority region for conservation and our results emphasize that conservation policies should be implemented in the region.(au)


Subject(s)
Animals , Behavior, Animal , Diet , Fauna/analysis , Snakes/classification
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