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Guilherme Augusto-Alves, Simone A. Dena and Luís F. Toledo

Abstract

Advertisement call is the most common signal used by anurans for intraspecific communication. However, some species have lost the ability to emit these vocalizations and are denoted as mute. Alternatively, these species may communicate by visual, tactile and chemical signals. The lack of advertisement call could be explained by the high background noise of breeding microhabitats. A model group to study alternative communication tactics is the genus Megaelosia, which is composed by seven mute species that inhabit noisy streams, and for which no information on intraspecific communication is available. We monitored a population of M. apuana and described its visual signalling during aggressive interactions between males. This interaction included visual signalling, physical combat, and the retreat of the smaller individual. No audible sound was detected during the whole aggressive interaction, reinforcing the genus muteness. This is the first report of any communication behaviour for the genus Megaelosia.

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Hublester Domínguez-Vega, Iriana Zuria and Leonardo Fernández-Badillo

Abstract

Salamanders are usually seen as typical inhabitants of temperate and humid habitats. Among Plethodontids, Isthmura bellii has the broadest altitudinal range of any salamander in the world and it is considered a habitat generalist. Nonetheless, even for this species, dry environments are thought unsuitable. We report the first records of I. bellii in arid tropical scrub from two localities within central Mexico. We analyze the environmental differentiation of these new localities in relation to the known distribution range of the genus. Our study shows that among the new localities, there is at least one site where I. bellii appears to have established in arid tropical scrub. An environmental model reveals that these new localities present different conditions than most of the records of Isthmura spp.

Open Access

Eva Ringler

Abstract

Skin swabbing, a minimally invasive DNA sampling method recently proposed for adult amphibians, was tested on the dendrobatid frog Allobates femoralis. I compared DNA yield from skin swabs and toe clips by evaluating obtained DNA concentrations and purity of extracts, as well as amplification success using eleven polymorphic microsatellite loci. I also tested whether storing skin swabs for two months at −20°C affected the properties of the extract or microsatellite analysis. Results show that skin swabs of adult A. femoralis suffered from high contamination and yielded significantly lower DNA quality and quantity, resulting in insufficient genotyping success, than DNA obtained from toe clips. The relatively dry skin in dendrobatid frogs may have impeded the collection of sufficient viable cells, and the presence of skin alkaloids and microbiota in the frog mucus may lead to high contamination load of skin swabs.

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Claudio Angelini, Andrea Tiberi, Bruno Cari and Filippo Giachi

Abstract

Global amphibian decline is a subject of great conservation concern, yet often basic demographic information is absent, which prevents the understanding of population trends and the planning of effective conservation management. We analysed capture-mark-recapture data from six populations of the endangered Bombina pachypus in order to understand the relative contribution of survival and recruitment to population growth, and to assess if any differences exist among populations in terms of their population dynamics. We found that survival was rather high and generally constant among sites, and recruitment was low, with the exception of two single years at one site. Population growth depended on survival on all sites, except the years following high recruitment at one site. Annual population size was generally lower than 30 individuals, but in one site it was estimated to be larger than 50. Our findings suggest that juvenile survival is more important for population dynamics than recruitment from the larval to the juvenile stage. We also suggest that the low recruitment rates we recorded was a result of juvenile dispersal, and that when populations exhibited high recruitment it was due to occasional successful migration or local recruitment. This pattern could represent a way to counterbalance the risk of inbreeding in populations composed of few individuals, a common characteristic of populations of B. pachypus. Finally, we suggest that conservation measures for B. pachypus should be planned at the landscape scale, and should not be limited solely to the breeding site and its close surroundings.

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Volkan Aksoy and Yilmaz Camlitepe

Abstract

Ants constitute one of the most intriguing animal groups with their advanced social lifes, different life histories and sensory modalities, one of which is vision. Chemosensation dominates all other modalities in the accomplishment of different vital tasks, but vision, varying from total blindness in some species to a relatively well-developed vision providing ants the basis for visually-guided behaviors, is also of importance. Although studies on ant vision mainly focused on recognition of and guidance by landmark cues in artificial and/or natural conditions, spectral sensitivities of their compound eyes and ocelli were also disclosed, but to a lesser extent. In this review, we have tried to present current data on the spectral sensitivities of the different ant species tested so far and the different methodological approaches. The results, as well as the similarities and/or discrepancies of the methodologies applied, were compared. General tendencies in ants’ spectral sensitivities are presented in a comparative manner and the role of opsins and ant ocelli in their spectral sensitivity is discussed in addition to the sensitivity of ants to long wavelengths. Extraocular sensitivity was also shown in some ant species. The advantages and/or disadvantages of a dichromatic and trichromatic color vision system are discussed from an ecological perspective.

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Volkan Aksoy and Yilmaz Camlitepe

Abstract

Ants constitute one of the most intriguing animal groups with their advanced social lifes, different life histories and sensory modalities, one of which is vision. Chemosensation dominates all other modalities in the accomplishment of different vital tasks, but vision, varying from total blindness in some species to a relatively well-developed vision providing ants the basis for visually-guided behaviors, is also of importance. Although studies on ant vision mainly focused on recognition of and guidance by landmark cues in artificial and/or natural conditions, spectral sensitivities of their compound eyes and ocelli were also disclosed, but to a lesser extent. In this review, we have tried to present current data on the spectral sensitivities of the different ant species tested so far and the different methodological approaches. The results, as well as the similarities and/or discrepancies of the methodologies applied, were compared. General tendencies in ants’ spectral sensitivities are presented in a comparative manner and the role of opsins and ant ocelli in their spectral sensitivity is discussed in addition to the sensitivity of ants to long wavelengths. Extraocular sensitivity was also shown in some ant species. The advantages and/or disadvantages of a dichromatic and trichromatic color vision system are discussed from an ecological perspective.

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Jun-yu Chen, Yu-lin Gao, Dong-yin Han, Lei Li, Fang-ping Zhang, Li-ming Niu and Yue-guan Fu

Abstract

Mango is an important tropical fruit, and thrips are important pests that have threatened mango yield and quality in recent years. It is important to determine the dominant species and distribution of thrips in mango for effective thrips control. In the present study, the species of thrips in mango flowers in the five main mango-producing provinces of China, and the species of thrips in different phenological stages of mango in Hainan Province were investigated. Thrips species on weeds in mango agroecosystems were also determined. The results indicated that in total there are 41 species of thrips in mango orchards in the five main mango-producing provinces of China, belonging to 21 genera, five subfamilies and three families. These are 31 species in 13 genera of Thripidae, nine species in seven genera of Phlaeothripidae, and one species in one genus of Aeolothripidae. The major species of thrips differed across the main mango production areas. Thus, 26, 17, 23, 12 and 7 species of thrips were collected in mango orchards in Hainan, Guangxi, Yunnan, Sichuan and Fujian, respectively. Frankliniella occidentalis (Pergande), an important invasive pest in China, was only discovered in mango orchards in Yunnan and Sichuan. Thrips species and population dynamics are closely related to the phenological stage of mango. In Hainan, the dominant thrips species during the shoot period and young fruit stage was Scirtothrips dorsalis Hood. In the flowering period, the thrips population increased significantly and species composition became complicated in the field, with Thrips hawaiiensis and F. intonsa being the dominant species. Frankliniella intonsa and T. hawaiiensis were the dominant species on weeds in the mango ecosystem, which was consistent with them being dominant thrips species on mango. It is speculated that in mango ecosystems, weeds provide refuge to thrips and removing weeds benefits thrips control in mango orchards during the flowering period.

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Colin Strine, Inês Silva, Curt H. Barnes, Benjamin M. Marshall, Taksin Artchawakom, Jacques Hill and Pongthep Suwanwaree

Abstract

The Big-Eyed Green Pit Viper (Trimeresurus macrops; Kramer, 1977) is a venomous snake species endemic to Southeast Asia. Although we have some knowledge of the systematics and toxicology of T. macrops, little is known about the spatial ecology of this species. From May 2013 to February 2014, we used radio-telemetry to determine home-range sizes of 13 adult female T. macrops inhabiting the Sakaerat Biosphere Reserve in Northeast Thailand. We found that individual home ranges for T. macrops averaged 0.175 ha, with activity areas ranging from 0.112-0.303 ha and core areas ranging from 0.023-0.052 ha. There was little overlap between conspecific tracked females, especially for the most used areas of their home ranges. We find that T. macrops ambushes more in higher humidity and expresses very little diurnal activity. They use the groundstory for ambushing, then retreat over small distances to higher refuge during the day. Future studies should focus on prey abundance, habitat selection, and survival rates.

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Marta Demkowska-Kutrzepa, Maria Studzińska, Monika Roczeń-Karczmarz, Krzysztof Tomczuk, Zahrai Abbas and Paweł Różański

Abstract

In the 20th century large numbers of exotic turtles Trachemys scripta elegans have been imported into Europe as pets and this has led to frequent introductions into many freshwater ecosystems. Nowadays, established populations of red-eared slider, coexist and compete with the native in Europe species of turtles in the wild. Invasive turtles are a threat to indigenous species because of carriage of many parasites, which are often considered to cause disease emergence and produce high mortality in native hosts. Helminths are the most prominent group introduced with T. s. elegans and due to their host-switching ability have become important co-invaders, a potential threat to indigenous turtle health. The aim of this review was to assess the risks of the transfer of helminths co-introduced with T. s. elegans to native species of European turtles.

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Dawson M. Brown and Matthew S. Lattanzio

Abstract

Intraspecific social dominance hierarchies should be influenced by environmental variation; however, in colour polymorphic species, dominance hierarchies are often assumed fixed, and thus insensitive to environmental variability. We ran a series of experiments using the colour polymorphic long-tailed brush lizard (Urosaurus graciosus) to challenge this assumption. We staged contests between orange and yellow morph males over a single heated perch, two perches at the same temperature, or two perches differing in temperature. Our first experiment revealed that orange-throated males are socially dominant. However, this hierarchy collapsed in our other experiments as yellow males became more aggressive. Interestingly, both males only ever secured their own perch where the perches differed in temperature. These findings mirror observations of morph behavioural flexibility in nature and studies of behaviour–environment interactions in non-polymorphic taxa. We conclude that colour morphs may have an underappreciated ability to assess resource-level changes and respond with concomitant flexibility in behaviour.