Abstract: We review the occurrence of vocalisations in tortoise courtship in order to investigate their functions, if any, taking into account evolutionary history, habitat and body size. Courtship behaviour has been described for 101 (41%) of all chelonian species. Among them, mount vocalisations occur in 35 species belonging to families Testudinidae Batsch, 1788 (n=29), Trionychidae Fitzinger, 1826 (n=3), Emydidae Rafinesque, 1815 (n=2), and Bataguridae = Geoemydidae Theobald, 1868 (including Batagurinae Gray, 1869) (n=1). The mapping of vocalisation evolution along the phylogenetic tree revealed that mount vocalisations are an ancestral trait, being present from the origin of Cryptodira, and calls mainly occur in terrestrial or semi-terrestrial species. In the species and subspecies of Testudinidae we considered, mounting-calls show an harmonic structure with frequency and amplitude modulation, which are acoustic features not compatible with mechanisms of sound production based simply on air flow through respiratory tracts. Moreover, the call fundamental frequency was negatively related to body size. Since in birds and amphibians such size-frequency relationship is due to a correlation existing between body size and mass of the vibrating device used to produce sounds (a greater device produces longer wavelengths and consequently low frequencies), in tortoises vocalisations might also be produced by vibrating structures not yet described. All these findings strongly suggest that mounting-calls might have the function to convey information on the signaller to conspecifics, possibly influencing the outcome of sexual interactions.

Keywords: CALL FREQUENCY, MOUNT VOCALISATIONS, BODY SIZE, CHELONIANS, PHYLOGENY

Abstract: We compared the effectiveness of three techniques for surveying frogs in four different habitats in a subtropical area of Taiwan. We conducted surveys biweekly from July 2000 to July 2001 employing three sampling techniques (nocturnal line-transects, automated recording systems, and side-flap pail-traps) concurrently in each of four habitats (temporary pond, permanent pond, ephemeral stream, and permanent marsh). We detected 22 species of anurans from five families, representing 76% of the anuran species found in Taiwan. Line-transect sampling and automated recorders detected 22 and 20 species respectively, with an average of 12.3±3.2 (mean±SD) and 10.4±3.5 species per survey. In contrast, traps only captured 11 species, with an average of 2.1±1.5 species per survey. Automated recorders were most effective at detecting hylids, rhacophorids, and microhylids that have loud calls and/or prolonged periods of calling. Recorders were less effective at detecting ranid and bufonid species that have relatively quiet calls. Traps were good at capturing most of the ranids, species that were usually missed with automated recorders. The combination of recorders and traps was equivalent to line-transect sampling, suggesting that these two techniques are a good alternative to nocturnal line-transect sampling, a technique that is difficult to use in remote areas and/or habitats that are inaccessible at night.

Keywords: TRANSECT, SURVEY METHODS, TRAPPING, AMPHIBIAN, SAMPLING

Abstract: Middle and Late Miocene fossils of the box turtle genus Terrapene are reviewed. The oldest known Terrapene specimens originate from the Medial and Late Barstovian North American Land Mammal Ages of Nebraska. Two nuchal bones from the Egelhoff Local Fauna, Keya Paha County, Nebraska (Medial Barstovian Land Mammal Age, ca 14.5-13.0 million BP) and a left hyoplastron from the Stewart Quarry, Cherry County, Nebraska (Late Barstovian, ca 13.0-11.5 million BP) closely resemble recent Terrapene ornata. The presence of T. ornata-like box turtles in the Barstovian suggests that the extant species groups were already established by that time and that the genus Terrapene evolved distinctly before the Middle Miocene. An extinct subspecies of T. ornata, T. o. longinsulae Hay, 1908, is known from the Late Miocene (Clarendonian, ca 11.5-9.0 million BP) as well as from several Pliocene sites. It is unknown whether a Clarendonian Terrapene hyoplastron from the Ash Hollow Formation of Cherry County, Nebraska belongs to T. o. longinsulae or to another taxon. A nearly complete anterior plastral lobe from the Myers Farm Local Fauna, near Red Cloud, Webster County, Nebraska, from the Late Barstovian (ca 13.0-11.5 million BP) differs significantly from all other recent and fossil Terrapene taxa. This specimen serves as the holotype of a new extinct Terrapene species described herein. It is of unclear relationships and shares some characters with T. coahuila and others with T. nelsoni and T. ornata. A left humerus from the WaKeeney Local Fauna, Trego County, Kansas (Middle to Late Clarendonian Land Mammal Age, ca 10.0-9.0 million BP) compares well with humeri of recent Terrapene carolina and is the oldest Terrapene that resembles extant T. carolina. The second oldest one is from the latest Miocene McGeehee Site, Alachua County, Florida (Early Hemphillian, ca 8.5 million BP) and perhaps represents a fossil taxon known as T. carolina putnami Hay, 1908.

Keywords: NORTH AMERICA, NEOGENE, CHELONIA, PALAEONTOLOGY, FOSSIL

Abstract: Although the majority of cordylids are solitary, some species display prominent grouping behaviour. We tested whether limited shelter availability is a factor responsible for the grouping behaviour observed in Cordylus cataphractus and C. macropholis, using the solitary-living C. polyzonus as control. In an experimental setup, individuals of each species were provided with an excess of shelter sites and the observed patterns of shelter occupation were compared among the three species. Cordylus cataphractus consistently aggregated, occupying fewer shelters than its two congeners. Grouping behaviour in C. cataphractus in the wild is not the result of a limitation of refuge sites. In contrast, shelter occupation by C. macropholis and C. polyzonus was random, hence non-aggregative. Thus, although the aggregative behaviour observed in C. macropholis in its natural habitat might be influenced by limited shelter availability, other causal factors can not be excluded empirically.

Keywords: CORDYLUS CATAPHRACTUS, CORDYLUS POLYZONUS, CORDYLIDAE, REFUGE AVAILABILITY, CORDYLUS MACROPHOLIS

Abstract: Body temperatures of 51 caimans in the Pantanal were monitored by radio telemetry in cool (dry season) and warm (dry and wet seasons) seasons in an area with isolated lakes and an area with intermittent rivers. Cloacal temperatures of 739 caimans of different sizes captured between 1830 hrs and 2200 hrs were measured with a digital thermometer between August 1996 and September 1999 in the same area. The masses of caimans monitored ranged from 3 to 42 kg, and caiman size affected the amplitude of body temperatures. Small caimans generally had lower mean body temperatures than larger caimans only at the beginning of the night in the cool season before body temperatures equilibrated with water temperatures. Mean body temperature was 25.7 °C in the cool season and 30.1 °C in the warm season, with a minimum of 16.9 °C and a maximum of 37.9 °C. In the warm season, caimans spent more time in shady areas, on land or in the water, than exposed directly to sunlight, and body temperatures only slightly exceeded water temperatures. In the cool season, caimans basked in the sun, both on land and in water, and caimans on land achieved body temperatures up to 15 °C above water temperatures, but body temperatures of caimans on land rarely exceeded air temperatures during daylight hours. Gravid females did not have higher temperatures than females that were not gravid. The caimans appeared to vary from near thermoconformity in the warm season to active thermoregulation when water temperatures were less than about 28 °C. However, caimans often appeared to give low priority to thermoregulation, and much shuttling behavior may occur for reasons unrelated to thermoregulation.

Keywords: CAIMAN CROCODILUS YACARE, BEHAVIOUR, THERMOREGULATION, TEMPERATURE

Abstract: Many reptile species dig underground nests where they deposit eggs with flexible and permeable shells that have physical contact with the soil and are highly permeable to soil water and gases. Iberian rock lizard eggs (Lacerta monticola cyrenni) incubated in acidic substrates suffered significant impairment to their development. Therefore, soil pollution could be affecting embryonic development. Low pH had a negative effect on egg water exchange, hatchling size and locomotor performance. In all cases, pH had no effect on incubation duration and embryo survival. At substrate pH of 4 and 10, eggs absorbed less water and final egg size and weight was lower than at neutral pH. Hatchlings from eggs incubated in acidic substrates had lower mass (up to 28 % of weight), SVL, and tail length than controls. Running speed – a good indicator of lizard fitness – was also affected by substrate pH. Embryos incubated at pH 4 ran slower than controls. The alteration of the water absorption process that low substrate pH had on eggs during incubation partially explained the observed effects on hatchling characteristics. These sublethal effects may influence the survival or success of juveniles during or after their first wintering.

Keywords: ECOTOXICOLOGY, SOIL PH, INCUBATION, LACERTIDS

Abstract: Post-metamorphic growth to sexual maturity was studied in a tropical frog Euphlyctis cyanophlyctis that breeds all the year round, in large outdoor terraria. Sexual size dimorphism (SSD) was studied in both a natural population and those reared in outdoor terraria. The growth rate was high in the first 2-3 months in both sexes, but subsequently declined, reaching a plateau following sexual maturation. The growth rate was high during summer and low during winter, and its pattern paralleled the changes in the ambient temperature. The males matured between 3-6 months depending upon their growth rates; at this stage they developed vocal sacs and spermatozoa and engaged in calling. The females matured between 8-11 months of age and responded to injections of progesterone by producing mature eggs. Fecundity was positively correlated to snout-vent length (SVL)/body mass. The males and females attained maturity when they reached a critical minimum SVL of ∼42 mm and ∼55 mm respectively. Mean adult body size (SVL and body mass) of females collected from nature was 67.0±0.85 mm and 32.8±1.56 g, and that of males was 48.0±0.37 mm and 10.1±0.31 g. Male to female size ratio (F/M) was 1.4 indicating SSD and a larger female size. In laboratory-reared specimens also, SSD was obvious at sexual maturity. A larger body size in females is due to delayed sexual maturity relative to the males. These findings suggest that in E. cyanophlyctis SSD is manifested primarily due to differences in the age at sexual maturity rather than an inherent difference in the postmetamorphic growth rate between the sexes.

Keywords: ANURA, AMPHIBIA, REPRODUCTION, SEX RATIO, AGE AT MATURITY

Abstract: The reliability of basking counts as indices of relative abundance for Emys orbicularis was tested in a pond system in central Italy. For different field conditions regression was carried out between basking indices and population size estimates obtained by capture and recapture methods. Regression was particularly significant in midday hours of sunny days from May to July, suggesting that in these conditions basking counts can be used as indices of population size.

Keywords: POPULATION ESTIMATES, ITALY, TURTLES, TERRAPINS

Abstract: Through the analysis of 1518 otter spraints we determined the importance of amphibians and reptiles in otter diet and the seasonal patterns of consumption of the different species in a heterogeneous coastal environment in southern Spain. Otters fed on a minimum of six amphibian and three reptile species. Amphibians were present in 13.2% and reptiles in 3.9% of the spraints analysed. Remains of amphibians and reptiles were significantly associated in otter spraints, but negatively associated with crayfish occurrences. Maximum reptile consumption occurred during the summer. Though terrapins have been rarely cited as otter prey, they were consumed more than twice as frequently as water snakes in the study area. The highest frequency of amphibians in the otter diet was recorded in late winter-spring surveys, coinciding with the spawning periods of most species. However, the frequency of amphibians remained high during summer months due to predation on the Iberian green frog (Rana perezi), a very aquatic frog that was almost the only amphibian species consumed in this season.

Keywords: PREDATION, MAUREMYS LEPROSA, BUFO BUFO, COASTAL OTTERS, MEDITERRANEAN STREAMS, RANA PEREZI

Abstract: We analysed the endoparasite fauna associated with two species of whiptail lizard (Cnemidophorus abaetensis and C. ocellifer) from north-eastern Brazil. Overall parasite prevalence was relatively low for both species (18.2% in C. abaetensis and 12.5% in C. ocellifer). Four parasite species were recorded: the pentastomid Raillietiella aff. furcocerca and the nematodes Physaloptera lutzi, P. retusa and Hexametra boddaertii. We compared our results with those of previous similar studies on other whiptails.

Keywords: PARASITES, HELMINTHS, SQUAMATES

Abstract: Effects of fluctuating temperatures on reptilian eggs and hatchlings are poorly known. We carried out a fluctuating-temperature incubation experiment with two treatments (27±3 °C vs 27±7 °C) to determine the effects of temperature and clutch of origin on incubation duration and the morphology and locomotor performance of hatchlings in a skink, Eumeces chinensis. The variance of fluctuating temperatures had no influences on incubation duration, hatching success or hatchling traits. Incubation temperature accounted for over 10% of the total variation in incubation duration and hatchling traits, whereas clutch effects accounted for much more. The discrepancy between these results and those from previous studies may be due to interspecific differences in embryonic response to thermal variance.

Keywords: MATERNAL EFFECT, EGG INCUBATION, TEMPERATURE

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