No abstract

Many uncertainties remain regarding our knowledge of sigmodontine rodent distributions in Northwestern Argentina. Most of the available information has never been critically evaluated. By reviewing the published literature and overlaying this information with other spatial layers (political, environmental, infrastructure, protected areas, and topographic layers), we identified information gaps and added new localities. The new records were obtained through field surveys, including captures and owl pellet samples. In the literature, we found 561 localities, most of them published in the past decade. These records come mainly from low-altitude areas in Salta province, as well as some higher-altitude belts in Yungas, and strongly associated with roads. Records from protected areas were scarce. Akodon, Calomys, Oligoryzomys, and Phyllotis were recorded for most of the localities. We add 18 new localities for 14 species, including the first records of Akodon dolores in Tucumán province, Necromys lasiurus in Santiago del Estero and Tucumán, and Calomys lepidus in Catamarca. We add records for poorly known species such as Andalgalomys olrogi in the Capital department (Catamarca) and Auliscomys sublimis and Neotomys ebriosus in Cochinoca (Jujuy) and La Poma (Salta). We emphasize the need for more surveys to obtain an adequate knowledge of the distribution of most sigmodontines.

In vitro maturation of oocytes recovered from dead animals provides an opportunity for rescuing genetic material for biodiversity conservation. The dorcas gazelle (Gazella dorcas) is regarded by the World Conservation Union (IUCN) as ‘vulnerable’ but the subspecies G. dorcas neglecta is thought to be endangered due to excessive hunting. A captive breeding program for dorcas gazelles has been developed at the Estacion Experimental de Zonas Aridas (CSIC) in the South of Spain where efforts have so far concentrated on natural breeding and on the development of sperm cryopreservation protocols. The aim of the present study was to explore the possibility of recovering and maturing in vitro healthy oocytes from animals that die suddenly for the establishment of a program to rescue female gametes. Ovaries of a dorcas female that died unexpectedly were collected about 7 h after death of the animal. Cumulus–oocyte complexes (COCs) were recovered by slicing the ovaries. Collection and washing of COCs were performed in warmed TCM-199-HEPES with antibiotics and polyvinyl alcohol. Degenerated oocytes or those with expanded cumulus cells were removed. A total of 15 COCs were cultured in TCM-199 with 10% heat-treated fetal calf serum, 10 μg/mL ovine FSH/LH, 1 µg/mL estradiol, and 0.1 mg/mL glutamine at 38.5°C under 5% CO2/air with high humidity. After 24 h of culture, matured oocytes, as revealed by the presence of a polar body, were activated with 7% ethanol for 10 min and further incubation for 3 h. Meiotic progression and activation were evaluated by staining with Hoechst 33342 and propidium iodide (1 μg/mL each) and visualization under a fluorescence microscope. Results at the end of incubations showed that 4/15 oocytes were degenerated, 4/15 were arrested at the MI stage, and 7/15 (46.7%) progressed to the MII stage. One oocyte was found to be at the 2-cell stage but it could not be established whether this was the result of the activation method used. These results demonstrate that it is possible to recover viable oocytes several hours after death and rescue them for subsequent in vitro maturation and fertilization. More studies are needed to characterize suitable conditions for oocyte maturation, fertilization, and culture in the dorcas gazelle. This would, in turn, help in the effort to rescue biomaterials from wildlife for generating offspring. This work was supported by the Spanish Ministry of Education and Science (REN 2003–01587) and Acciones Integradas (HI20030336).

Review of the geographic distribution of Micrurus decoratus (Jan, 1858) (Serpentes: Elapidae). Micrurus decoratus (Jan, 1858) is a poorly known species of coral snake, with a controversial history concerning its geographical range. The lack of consensus among researchers, since its original description, is largely due to the reporting of erroneous localities in publications. Herein we present the geographical range for the species based on the review of 184 records from 67 different municipalities in Brazil, including two new records for the state of Espírito Santo, extending its distribution to ca. 300 km northward from the previous northernmost locality. We also comment on doubtful records for the states of Rio Grande do Sul and Bahia, which contain no accurate data. We restrict the occurrence of Micrurus decoratus to the Atlantic Rainforest, with elevation range from 400 up to 1,600 m in the Brazilian states of Santa Catarina, Paraná, São Paulo, Rio de Janeiro, Minas Gerais and Espírito Santo.

Sigmodontine rodents are well represented in northwestern Argentina, but information regarding their distribution in La Rioja is scarce. We add new information for seven species from seven localities in the Famatina range. These new records were obtained using both captures and owl pellet analysis. We cite the first record of Neotomys ebriosus in La Rioja. The collection locality is unusual for this species because of its low altitude and xeric conditions. Other notable results include the second record of Abrothrix andinus and of the genus Oligoryzomys at the province.