A new species of sucking louse (Psocodea: Phthiraptera: Anoplura: Hoplopleuridae) from the pale field rat, Rattus tunneyi (Rodentia: Muridae), in Australia

We describe and illustrate a new species of sucking louse, Hoplopleura tunneya new species, from the Australian pale field rat, Rattus tunneyi Thomas (Rodentia: Muridae). Currently, 22 species of the genus Hoplopleura Enderlein, 1904 (Phthiraptera: Anoplura: Hoplopleuridae) are known from Australian endemic rodents. Among the seven “new endemic” rodent species of the genus Rattus in Australia, R. tunneyi is one of five hosts to Hoplopleura lice. In addition, we give a list of all the species of Hoplopleura known from Australian endemic rodents. Including the introduced species Polyplax spinulosa, the total number of sucking louse species known from Australian endemic rodents is now 24.

Comparing the electrophysiological effects of traumatic noise exposure between rodents

Noise-induced hearing deficits are important health problems in the industrialized world. As the underlying physiological dysfunctions are not well understood, research in suitable animal models is urgently needed. Three rodent species (Mongolian gerbil, rat and mouse) were studied to compare the temporal dynamics of noise-induced hearing loss after identical procedures of noise exposure. Auditory brainstem responses (ABRs) were measured before, during and up to eight weeks after noise exposure for threshold determination and ABR waveform analysis. Trauma induction with stepwise increasing sound pressure level was interrupted by five interspersed ABR measurements. Comparing short- and long-term dynamics underlying the following noise-induced hearing loss revealed diverging time courses between the three species. Hearing loss occurred early on during noise exposure in all three rodent species at or above trauma frequency. Initial noise level (105 dB SPL) was most effective in rats while the delayed level-increase to 115 dB SPL affected mice much stronger. Induced temporary threshold shifts in rats and mice were larger in animals with lower pre-trauma ABR thresholds. The increase in activity (gain) along the auditory pathway was derived by comparing the amplitudes of short- and long-latency ABR waveform components. Directly after trauma, significant effects were found for rats (decreasing gain) and mice (increasing gain) while gerbils revealed high individual variability in gain changes. Taken together, our comparative study revealed pronounced species-specific differences in the development of noise-induced hearing loss and the related processing along the auditory pathway.

First photographic record of albinism in Baiomys taylori (Rodentia: Cricetidae)

Cases of albinism have been reported in less than 2% of living rodent species. Here, we report the first description of complete albinism in Baiomys taylori along with photographic evidence. This adult female was captured on three occasions as part of a long-term small mammal study on rangelands of extreme southern Texas. The individual was developing teats upon the third capture, an early sign of pregnancy. Despite selective pressures against albino phenotypes, this animal was able to survive to adulthood and potentially pass its albino alleles to offspring.

Mammal fauna of Chisinau airport, Republic of Moldova

Introduction. Airport territories are large, containing a high variety of biotopes, mostly open type, and are relatively protected against intense human activity, thus creating favorable conditions for many mammal species that serve as trophic source for many bird species. Material and methods. The studies were performed during 2012-2014 on the territory of Chisinau airport and within the adjacent ecosystems. The mammals were recorded by direct observations, based on traces and trophic activity on routes ranging from 1 to 3 km. The small mammals were assessed with traps. The bat species were identified according to their flight pattern and using the ultrasound detector. Results. In the airport, 31 species of mammals were registered: 5 insectivore species, 7 bat species, 14 rodent species, 1 hare species and 4 carnivorous species. The most widespread, common and abundant were the rodents and the fox. Among small rodent species, the most abundant was Apodemus sylvaticus with 51.6%, followed by the Microtus arvalis (38.9%), while on the airport grassland, the field vole dominated with more than 60%. The diet of Athene noctua included predominantly Mus musculus with over 51%, followed by M. arvalis with 23.7%. 7 species are rare and 5 protected – bicolor shrew and 4 bat species. Conclusions. The airport territory and adjacent ecosystems provide favorable conditions for many mammal species. The presence of rodents favors the occurrence of rather high number of prey birds, which represent a threat for the safety of aircraft flights. The fox can pose direct threat to flight safety.

Influence of vegetation structure, seasonality, and soil physical properties on rodent species diversity and community assemblages on West Mount Kilimanjaro, Tanzania.

A study on rodent species diversity and community assemblages in West Mt Kilimanjaro was conducted in seven different habitats, covering two dry and wet seasons. Data were collected using a combination of medium-sized Sherman’s live traps, snap and Havarhart traps, for three consecutive nights. General Linear Models (GLM) were used to analyze the effects of predictors (vegetation attributes, seasonality, soil physical properties, disturbance and altitude) on rodent species richness and abundance. Community structure analysis was conducted in the Primer v6 program and Canonical correspondence analysis for habitat association in PAST. A total of 1,393 individuals from 14 species of rodents were trapped. The most dominant rodent species were Rhabdomys pumilioPraomys delectorum, and Lophuromys verhageni which contributed to 68.86% of the total captures. Lophuromys verhageni occurred across all the habitats and seasons. Moreover, habitat types, seasonality, soil texture, ground cover, and altitude significantly influenced rodent species abundance (P< 0.05). Furthermore, habitat types, seasonality and altitude significantly influenced rodent species richness (F8, 759 = 629.7, p< 0.001, R2 = 0.87). In addition to that, two major rodent communities were formed in different habitats. The results show that rodent species richness, abundance, and community assemblages in Mt Kilimanjaro, are a result of change in vegetation structure along the altitudinal gradients. Therefore, information on habitat requirements of multiple species is crucial for the management and conservation of these communities.

Emerging hantaviruses in Central Argentina: First case of Hantavirus Pulmonary Syndrome caused by Alto Paraguay virus, and a novel orthohantavirus in Scapteromys aquaticus rodent

Orthohantaviruses are emerging rodent-borne pathogens that cause Hantavirus Pulmonary Syndrome in humans. They have a wide range of rodent reservoir hosts and are transmitted to humans through aerosolized viral particles generated by the excretions of infected individuals. Since the first description of HPS in Argentina, new hantaviruses have been reported throughout the country, most of which are pathogenic to humans. We present here the first HPS case infected with Alto Paraguay virus reported in Argentina. Until now, Alto Paraguay virus was considered a non-pathogenic orthohantavirus since it was identified in a rodent, Holochilus chacarius. In addition to this, with the goal of identifying potential hantavirus host species in the province of Santa Fe, we finally describe a novel orthohantavirus found in the native rodent Scapteromys aquaticus, which differed from other hantaviruses described in the country so far. Our findings implicate an epidemiological warning regarding these new orthohantaviruses circulating in Central Argentina as well as new rodent species that must be considered as hosts from now on.

Spatial and Temporal Distribution of Rodents during the Epizootic and Enzootic Periods of Plague, with a Focus on Exu, Northeastern Brazil

The plague caused by the Yersinia pestis bacterium is primarily a flea-transmitted zoonosis of rodents that can also be conveyed to humans and other mammals. In this work, we analyzed the spatial and temporal distribution of rodent populations during epizootic and enzootic periods of the plague in the municipality of Exu, northeastern Brazil. The geospatial analyses showed that all the rodent species appeared through the whole territory of the municipality, with different occurrence hotspots for the different species. Important fluctuations in the rodent populations were observed, with a reduction in the wild rodent fauna following the end of a plague epizootic period, mostly represented by Necromys lasiurus and an increase in the commensal species Rattus rattus. A higher abundance of rats might lead to an increased exposure of human populations, favoring spillovers of plague and other rodent-borne diseases. Our analysis highlights the role of wild rodent species as amplifier hosts and of commensal rats (R. rattus) as preserver hosts in the enzootic period of a specific transmission infection area.