Blanca Beatriz Álvarez

Serous cutaneous glands in Phyllomedusa hypochondrialis (Anura, Hylidae): secretory patterns during ontogenesis.

Three syncytial gland types (Ia, Ib, and II ) have been described in the skin of larval, juvenile and adult Phyllomedusa hypochondrialis, which share the ultrastructural traits common to the serous secretory units of anuran skin, although each manufactures a peculiar product. Type la secretion consists of dense granules provided with a peculiar substructure, type Ib of vesicles holding a lucent material, type II of lipid deposits. None of the developmental stages investigated showed intermediate features between any of the three cutaneous products, which accumulate in the syncytial cytoplasms of the secretory units following different biosynthetic pathways, consistent with each gland type. These findings confirm previous results on adult specimens of P. hypochondrialis and P. sauvagei and stress the polymorphism of the serous glands in the genus Phyllomedusa. This morphological variability reflects the wide adaptive flexibility of serous glands in anurans.

Serous cutaneous glands of Argentine Phyllomedusa Wagler 1830 (Anura Hylidae): secretory polymorphism and adaptive plasticity

An ultrastructural study has been carried out on the cutaneous serous glands in the Argentine hylids Phyllomedusa sauvagei Boulenger 1882 and P. hypochondrialis Boulenger 1882. Both species possess type I serous units, which are representative of the usual serous glands in anurans, and type II units, peculiar to the genus Phyllomedusa Wagler 1830. Type I secretory units were further characterized as type Ia and Ib, on account of the morphology of their specific products. Type Ia secretory materials consist of spheroidal granules (4–6 μm in diameter), which are compact in P. sauvagei and provided with a mesh-like substructure in P. hypochondrialis. Type Ib serous deposits in P. sauvagei are also granules, which exhibit variable density, irregular shape, and are usually larger (up to 15 μm in diameter), whereas in P. hypochondrialis they are even wider vesicles (up to 20 μm), holding a finely dispersed material. No intermediate forms were detected between these features, and therefore the type I secretory u...

Descripción del sincraneo de Ameiva Ameiva (Linnaeus) (Squamata, Teiidae)

An osteological description of the syncranium and hyoid apparatus of Ameiva ameiva (Linnaeus, 1758) is presented. By comparison between males and females signiflcant intersexual differences were found in relation to: skull size, frontal, parietal and basisphenoid bones, interpterygoid opening and teeth number and mor-phology. Absence of pterygoid teeth in A. ameiva is verified out. The specimens used for this study carne from Chaco and Formosa provinces (Argentina).

Herpetofauna de la Reserva Natural Provincial Isla Apipé Grande (Corrientes, Argentina)

. Los inventarios de fauna silvestre son elementales para conocer la riqueza de especies donde la biodiversidad local aun se desconoce. Este es el caso de la Reserva Natural Provincial Isla Apipe Grande (Corrientes, Argentina), que incluye a gran parte de la Isla Apipe Grande, una de las islas con mayores dimensiones en el rio Parana. Para inventariar las especies de anfibios y reptiles de la Reserva se realizaron 18 viajes de campanas a la isla durante el periodo mayo de 2007-febrero de 2013. Las tecnicas empleadas fueron de observaciones directas y/o busquedas activas, y adicionalmente para anuros, transectos auditivos e inspecciones en sitios de apareamiento. Se registraron 63 especies: 27 anuros, 9 lagartos, 23 serpientes, 2 anfisbenidos y 2 cocodrilos. La completitud del inventario fue del 78% acuerdo al estimador de riqueza de especies Jackknife 2. Entre las especies registradas, 2 estan categorizadas como Amenazada ( Anisolepis longicauda e Hydrops caesurus ), 5 como Vulnerable ( Liolaemus azarai, Kentropyx viridistriga, Eunectes notaeus, Phimophis guerini , y Micrurus altirostris ), y 1 como Insuficientemente Conocida ( Apostolepis dimidiata ). Los anfibios y reptiles presentes en la Reserva Natural Provincial Isla Apipe Grande representan aproximadamente el 39% de la herpetofauna de la provincia de Corrientes, e incluye principalmente especies que se distribuyen en la region fitogeografica chaquena.

Diversity of teiid lizards from Gran Chaco and Western Cerrado (Squamata: Teiidae)

The Gran Chaco dry forest ecoregion corresponds to the southern portion of the South America diagonal belt of open formations, being one of the most threatened subtropical woodland savannas in the world. The area is still poorly known biologically and has been suffering with impressively high forest cover loss in the last 10 years. Integrating morphological and molecular data, we detected and describe a cryptic new species of lizard genus Ameivula endemic from the eastern part of this ecoregion, the called Humid Chaco. Ameivula apipensis sp nov. is characterised by a whitish brown vertebral stripe in adults and juveniles, a lateral field without ocelli and with overlapping spot, presence of an interfrontoparietal scale in 46.2% of the specimens, 12–17 femoral pores, an hemipenis without lateral sac, five xiphisternal ribs, and by a combination of meristic features as confirmed by discriminant analysis. The new species was recovered sister to a clade from Western Cerrado in our analysis, the first phylogenetic hypothesis for the Ameivula and Glaucomastix genera based on 1977 base pairs of three mitochondrial (12S, 16S and cyt‐b) and one nuclear (c‐mos) genes, including all the recognised species at the moment. Maximum parsimony and Bayesian inference recovered the monophyly of Ameivula and Glaucomastix with strong support. Reinforcing previous studies, our results suggest the presence of additional cryptic species in Ameivula from the Western Cerrado.

Comparative Study of Prenatal Development Between Myotis albescens (Chiroptera: Vespertilionidae) and Eumops patagonicus (Chiroptera: Molossidae): The Chorionic Vesicle and Extraembryonic Membranes Considerations: Comparative Study of Prenatal Development Between Myotis albescens Eumops patagonicus

We presented a comparative study of two species of South American bats, Myotis albescens and Eumops patagonicus, about prenatal development. This study was carried out using 60 specimens, which were measured and photographed, and the embryonic stage was assigned by the staging system for Carollia perspicillata. We observed that the chorionic vesicle showed similarities in the disposition of the extraembryonic membranes, but they differed in characteristics of their yolk sac; in E. patagonicus, it was more glandular than M. albescens. M. albescens presented a well‐developed discoid placenta with a caudal antimesometrial position, but E. patagonicus presented a diffuse placenta, which persists until the end of gestation and a discoid placenta in the uterus–tubal junction. In the embryogenesis, early stages, middle stages, and late stages were defined. In the early stage, the embryonic morphology is similar in the two species. The middle stage is characterized by the muzzle and pinna formation, fore and hind limb regionalization, and the formation of the patagium primordium. In the late stage, the overall growth of the embryo occurs. Its fore and hind limbs, patagium, and the typical craniofacial features are configured. We conclude that in early stages of development, the embryonic morphology of M. albescens and E. patagonicus is similar, while in late stages differences are evident; mainly the craniofacial structures and uropatagium configuration characteristics that allow their classification at the family level. Moreover, differences in time of fusion of maxillary and mandibular process were registered. This could be related to the morphology of the muzzle of each species. Anat Rec, 301:1527–1543, 2018.

Reproductive aspects of Dendropsophus sanborni (Anura, Hylidae) in northeastern Argentina

Reproductive aspects of Dendropsophus sanborni (Anura, Hylidae) in northeastern Argentina. The aim of this investigation was to characterize reproductive aspects of Dendropsophus sanborni (Schmidt, 1944) (Anura, Hylidae) in the northwest of Corrientes province, in northeastern Argentina. The reproductive cycles of males and females, the existence of sexual dimorphism and the male’s vocalization period were analyzed. Samplings were made from September 2011 to August 2012. Dendropsophus sanborni showed a prolonged reproductive pattern because reproductive activity was observed during most part of the year. Calling males were recorded all months except in July. The spermatogenic cycle can be characterized as potentially continuous. In males, snout-vent length was significantly correlated with mean testicular volume. The species showed sexual dimorphism in body mass, with females larger than males. Post-ovulatory females were found from March to June and most females had oocytes at different stages of maturity, with abundant post-vitellogenic oocytes from August to December.

Distribución y comentarios sobre la dieta de Rhinella azarai (Anura, Bufonidae) en Corrientes, Argentina

En esta contribucion se dan a conocer nuevas poblaciones de R. azarai para la provincia de Corrientes (Argentina), y se brinda informacion sobre la composicion de la dieta de una de ellas.