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Ebola virus (EBOV) disease is a viral hemorrhagic fever with a high case-fatality rate in humans. This disease is caused by four members of the filoviral genus Ebolavirus, including EBOV. The natural hosts reservoirs of ebolaviruses remain to be identified. Glycoprotein 2 of reptarenaviruses, known to infect only boa constrictors and pythons, is similar in sequence and structure to ebolaviral glycoprotein 2, suggesting that EBOV may be able to infect reptilian cells. Therefore, we serially passaged EBOV and a distantly related filovirus, Marburg virus (MARV), in boa constrictor JK cells and characterized viral infection/replication and mutational frequency by confocal imaging and sequencing. We observed that EBOV efficiently infected and replicated in JK cells, but MARV did not. In contrast to most cell lines, EBOV-infected JK cells did not result in an obvious cytopathic effect. Surprisingly, genomic characterization of serial-passaged EBOV in JK cells revealed that genomic adaptation was not required for infection. Deep sequencing coverage (>10,000×) demonstrated the existence of only a single nonsynonymous variant (EBOV glycoprotein precursor pre-GP T544I) of unknown significance within the viral population that exhibited a shift in frequency of at least 10 per cent over six serial passages. In summary, we present the first reptilian cell line that replicates a filovirus at high titers, and for the first time demonstrate a filovirus genus-specific restriction to MARV in a cell line. Our data suggest the possibility that there may be differences between the natural host spectra of ebolaviruses and marburgviruses.

Case report A 5-year-old captive male diamond python (Morelia spilota spilota) was presented with a 1-month history of regurgitation and anorexia and discrete coelomic distention. Physical examination revealed a firm, immobile mass at approximately two-thirds of the snout–vent length from the front of the head. Ultrasound-guided fine needle aspirate biopsy of the mass in the region of the stomach showed necrosis with bacterial infiltration and possibly neoplastic changes. A gastroscopy was conducted, but showed grossly normal gastric mucosa, confirmed by biopsy. On exploratory coeliotomy, it was confirmed the mass involved most of the stomach wall and occluded the gastric lumen. The mass was completely excised and based on histopathology, a diagnosis of gastric adenocarcinoma was made. The snake was found dead 12 h postoperatively, but no specific cause of death was found on postmortem examination. Conclusion Most cases of adenocarcinoma in snakes go undiagnosed. This case report illustrates that the architecture of gastric masses may lead to false-negative gastric biopsy results in snakes with neoplasia.

Understanding an organism's home range is an important component of effective wildlife management. However, home ranges can vary spatially and temporally within and between populations. Landscape ecology theory can provide a framework for understanding spatio-temporal variability in animal traits. We used radio-telemetry in a population of diamond python Morelia spilota spilota Lacepede (Pythonidae) from a biologically rich and structurally heterogeneous reserve in eastern Australia to explore the relationship between home range size, optimal foraging theory and vegetation mosaic theory. Twelve adult snakes were tracked between September 2004 and February 2008. Male home ranges were significantly larger (P

1. The interface between thermal biology and foraging mode has attracted little scientific attention, but may be crucially important to the biology of ectothermic predators. Slip & Shine (1988c) suggested that the ability of large heavy-bodied snakes to ambush nocturnally active mammals relied on the snakes’ control of cooling rates through their thermal inertia (via body size and postural adjustments) and microhabitat selection. 2. We tested assumptions underlying this hypothesis, using Diamond Pythons (Morelia s. spilota) from southeastern New South Wales. Our laboratory studies confirmed that larger body sizes and coiled postures significantly retarded cooling rates, and that body temperature affected the snakes’ ability to detect potential prey items. 3. The magnitude of these effects on cooling rates was great enough to extend the time period substantially over which an adult Diamond Python, lying in ambush in a suitable microhabitat, would be able to detect and capture nocturnally active prey. For example, the times taken for pythons to reach thermal equilibration under our experimental conditions (cooling from 33 to 12°C) were

AND R. A. DANIELS. 1982. Distribution and ecology of stream fishes of the Sacramento-SanJoaquin drainage system, California. I. Fishes of the Pit River system, McCloud River system, and Surprise Valley region. Univ. Calif. Publ. Zool. 115. PIMENTEL, R. A. 1979. Morphometrics. The multivariate analysis of biological data. Kendall/Hunt Publishing Co., Dubuque. , AND D. S. FREY. 1978. Multivariate analysis of variance and discriminant analysis, p. 247-274. In: Quantitative ethology. P. W. Colgan (ed.). John Wiley, New York. ROBINS, C. R., AND R. R. MILLER. 1957. Classification, variation, and distribution of the sculpins, genus Cottus, inhabiting Pacific slope waters in California and southern Oregon, with a key to the species. Calif. Fish Game 43:213-233. RUTTER, C. 1908. The fishes of the Sacramento-San Joaquin basin, with a study of their distribution and variation. US Bur. Fish. Bull. 27:103-152. SNYDER, J. 0. 1917. The fishes of the Lahontan system of Nevada and northeastern California. Ibid. 35:31-86.

Diamond pythons (Morelia s. spilota) are large (to 3 m) snakes of temperate-zone coastal eastern Australia. Foraging behavior was studied by observation of telemetered snakes, and diets deter- mined by dissection of museum specimens and collection of fecal samples from wild-caught snakes. Five adult snakes monitored in the field by radiotelemetry were found to be ambush foragers. In summer, telemetered snakes spent more than 80% of their time coiled, usually in a disinctive ambush posture near mammal trails. Telemetered snakes found feeding had occupied the site for at least a day beforehand. The diet of adult diamond pythons consisted almost entirely of mammals (91% of 44 records), mainly Rattus rattus and R. fuscipes (52%). Birds (9%) were taken infrequently. Juveniles ate mainly mammals (69%) and reptiles (23%). Larger snakes consumed larger prey. Hatchlings in captivity showed a preference for copper- tailed skinks, Ctenotus taeniolatus, but would also take newborn mice. Feeding occurred mainly in late spring, summer and early autumn. In terms of feeding biology, diamond pythons may be more similar to viperid snakes of other continents than to the elapids or colubrids with which they are sympatric.

Temperature-sensitive radiotransmitters were implanted in 18 free-ranging diamond pythons (Morelia spilota), and the snakes monitored for 4-34 mo. Body temperatures rose during a period of morning basking to between 28 and 30 C then fell gradually until the following morning. Unlike many other heliothermic reptiles, diamond pythons generally showed only one period of basking each day. Overt shuttling behavior did not occur, but behavioral modifications such as postural adjustments and the use of insulated microhabitats were used to reduce the rate of heat loss. Body temperatures were lower on cloudy days than on clear days, mainly because of reduced opportunities for basking. Mean body temperatures on clear days were lower in winter than in other seasons, mainly because of higher cooling rates. On clear days, snakes under cover were relatively cool (mean ? SD = 23.6 ? 5.35 C), and much warmer when they were active (27.7 ? 4.26 C). On cloudy days, body temperatures were lowest when snakes were coiled in the open (20.9 + 3.00 C) and highest when snakes were basking (25.4 ? 3.93 C) and moving (25.4 ? 4.08 C). Thermoregulation of large terrestrial snakes may be profoundly influenced by their high but variable thermal inertia: low heating rates militate against shuttling heliothermy, but behavioral and physiological control of cooling rates confers an ability to remain relatively warm even when ambient temperatures fall rapidly. In nocturnal ambush predators like the diamond python, heatconserving behaviors (coiling immobile in sheltered microhabitats) are compatible with foraging and may extend the range of times and ambient temperatures over which the snake can capture prey.