Taxonomy and Stratigraphy of Late Mesozoic Anurans and Urodeles from China

Three anurans (Callobatrachus sanyanensis, Liaobatrachus grabaui, Mesophryne beipiaoensis) and six urodeles (Laccotriton subsolanus, Liaoxitriton zhongjiani, Jeholotriton paradoxus, Sinerpeton fengshanensis, Chunerpeton tianyiensis, Liaoxitriton daohugouensis) are reported from the late Mesozoic tuff-interbedded lacustrine deposits (mostly of the Jehol Group) in northeastern China. They document the first discovery of Chinese Mesozoic lissamphibians, and their old geological age, superb preservation condition, and large taxoncmic diversity are unique compared with other findings worldwide. The anurans occupy a higher evolutionary position than typical Jurassic taxa, supporting a post-Late Jurassic age of the fossil horizons. The urodeles all have unicapitate ribs, suggesting an evolutionary grade at the cryptobranchoid level, and are advanced in osteological features over non-urodeles from the Middle and Upper Jurassic in England and Central Asia. Some urodeles (Jeholotriton and Chunerpeton) exhibit neotenic features, representing the earliest occurrence among such findings. Six fossil horizons are rscognized for the known Chinese Mesozoic anurans and urodeles: the Daohugou fossil bed, the Dabeigou Formation, the Lujiatun Bed, Jianshangou Bed and Dawangzhangzi Bed of the Yixian Formation, and the Jiufotang Formation. As implied from the osteological and phylogenetical studies, the geological age of these anurans and urodeles is the Early Cretaceous.

A Review for Life-history Traits Variation in Frogs Especially for Anurans in China

Environmental variation can promote differentiation in life-history traits in species of anurans. Increased environmental stress usually results in larger age at sexual maturity, older mean age, longer longevity, slower growth, larger body size, and a shift in reproductive allocation from offspring quantity to quality, and a stronger trade-off between offspring size and number. However, previous studies have suggested that there are inconsistent geographical variations in life-history traits among anuran species in China. Hence, we here review the intraspecific patterns and differences in life-history traits（i.e., egg size, clutch size, testes size, sperm length, age at sexual maturity, longevity, body size and sexual size dimorphism） among different populations within species along geographical gradients for anurans in China in recent years. We also provide future directions for studying difference in sperm performance between longer and shorter sperm within a species through transplant experiments and the relationships between metabolic rate and brain size and life-history.

Acoustic characteristics of eight common Chinese anurans during the breeding season

Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families （Ranidae, Microhylidae, Megophryidae and Bufonidae） from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the ＂Praat＂ software. Five acoustics parameters were measured, including temporal traits （call duration, number of notes or pulse number/call） and spectral traits （fundamental frequency, the first three formants and dominant frequency）. The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans.

Ecological and Geographical Reasons for the Variation of Digestive Tract Length in Anurans

Changes of environmental conditions can shape organs size evolution in animal kingdoms. In particular, environmental changes lead to difference in food resources between different habitats, thereby affecting individual’s energy intake and allocation. The digestive theory states that animals consuming food with low contents of digestible materials should result in increasing gut length. In this study, to test the hypothesis of digestive theory, we studied ecological and geographical reasons for variation in digestive tract length among 35 species of anurans distributing in different altitude and latitude. The results showed that ecological type significantly affected digestive tract length among species, with aquatic and terrestrial species having longer digestive tract than arboreal ones. Latitude was positively correlated with digestive tract length. However, altitude, as well as monthly mean temperature and precipitation, did not correlate with digestive tract length among species. Our findings suggest that aquatic and terrestrial species might forage less digestible materials than arboreal species, thereby displaying relatively longer digestive tract than arboreal species.

Changes on Anuran Tadpole Functional Diversity along an Environmental Gradient at the Southernmost Atlantic Rainforest Remnant

For decades the ecologists are using the same methods in order to determine the environmental health of a community,however,the crescent need on defining how these processes act,triggered the development of new methods that could classify the organisms and their function at the habitats.Here we used the anuran larvae to understand the effects of an environmental gradient on the structure and organization of the anuran assemblages along it,and to access in a realistic form,the actual state of preservation of the la rgest remnant of Atlantic Rainforest on the Southernmost portion of Brazil.We found that despite the higher diversity of species and the conservation unit status of the place,the ecosystem itself is still in danger,given the low number of functional groups and thus a higher number of ecosystem services that can be lost.

Soundscape Dynamics at Anuran Reproductive Sites in Pannonian Biogeographical Region：Effects of Road Noise on Vocal Activity

The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek soundscapes. The sensitivity of anuran breeding leks to acoustic disturbances makes breeding leks an important venue for a comparative soundscape study. We made long-term（〉 24 h） sound recordings in three representative wetlands and short-term（〈 30 min） recordings in ten sites in the Pannonian Biogeographical Region of Hungary and around the Hungary and Slovakia border. Long-term soundscapes of the floodplain stretch, where there is relatively minor anthrophonical disturbance, showed an obvious circadian change in sound intensities. The site with moderate sound contamination exhibited a disturbed pattern of circadian sound variation, while the site with heavy traffic noise displayed an apparently random temporal soundscape. At different amphibian breeding sites during mating season, our short-term recordings were dominated by anuran calls, bird songs and wind noises, while insect calls and rain were present to a lesser degree. Our study indicates that vehicle traffic noise is a severe imposition to the natural soundscape, and suggests that soundscape monitoring can provide a reliable and sensitive index of environmental change for both short-term and long-term periods.

Perception and Recognition of Vocalization in Anuran Mate Choice

Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral neuroscience.The present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere dominance.Investigations on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling systems.We proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.

Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China

In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection.

丽水树蛙产卵地微生境特征研究

丽水树蛙Zhangixalus lishuiensis为中国浙江省特有种。2022年3—5月,在丽水市景宁望东垟省级自然保护区对其繁殖生境进行了研究,使用样方法共测量28个样方,记录了水温、水体pH、植被类型等13个生境因子,通过分析丽水树蛙的生境喜好。结果表明:丽水树蛙倾向于在草或者苔藓下挖洞产卵,邻近清澈、含氧量较低、中等水深的碱性水体,且避开水温较高的地方;水体因子和植被因子是影响丽水树蛙生境利用的主要因素。建议加强丽水树蛙繁殖生态学研究,实施栖息地保护和修复措施。

Anuran interorbital distance variation:the role of ecological and behavioral factors

Eye position varies significantly among taxonomic levels,and this variation is often shaped by ecological and behavioral factors.Eye position is often positively associated with interorbital distance where species with broad visualfields possess a large distance between the left and right eye.Selective pressures underlying the evolution of the eye position are especially studied in birds and mammals.However,selective pressures underlying the evo-lution of anuran eye position which can be indicated by interorbital distance keep unknown.Here,we investigated the effects of ecological(e.g.habitat type,light availability)and behavioral factors(e.g.activity pattern,foraging mobility,and defensive strategy)on variations in interorbital distance among 260 anuran species in China.Our results showed that variations of the interorbital distance can be significantly predicted by the activity pattern.Noc-turnal species had larger interorbital distance than both nocturnal and diurnal species.We also found that foraging mobility and defensive strategy markedly affected variation of interorbital distance.Species having slower foraging mobility and possessing poison glands had larger interorbital distance than species having faster foraging mobility and possessing non-position glands.Light availability tended to be associated with variation of interorbital distance,indicating that species living in weak light tended to possess larger interorbital distance.However,variations of the interorbital space were not associated with habitat type in anurans.Ourfindings suggest that anuran behaviors play key roles in shaping visualfields and eye position,thus affecting the evolution of interorbital distance.

Cerebrovascularβ-dystroglycan immunoreactivity in vertebrates:not detected in anurans and in the teleosts Ostariophysi and Euteleostei

The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates,because dystroglycan,which is localized in the vascular astroglial end-feet,has a pivotal function in glio-vascular connections.In mammalian brains,the immunoreactivity ofβ-dystroglycan subunit delineates the vessels.The results of the present study demonstrate similar patterns in other vertebrates,except for anurans and the teleost groups Ostariophysi and Euteleostei.In this study,we investigated 1 or 2 representative species of the main groups of Chondrichthyes,teleost and non-teleost ray-finned fishes,urodeles,anurans,and reptiles.We also investigated 5 mammalian and 3 bird species.Animals were obtained from breeders or fishermen.The presence ofβ-dystroglycan was investigated immunohistochemically in free-floating sections.Pre-embedding electron microscopical immunohistochemistry on Heterodontus japonicus shark brains demonstrated that in Elasmobranchii,β-dystroglycan is also localized in the perivascular glial end-feet despite the different construction of their blood-brain barrier.The results indicated that the cerebrovascularβ-dystroglycan immunoreactivity disappeared separately in anurans,and in teleosts,in the latter group before its division to Ostariophysi and Euteleostei.Immunohistochemistry in muscles and western blots from brain homogenates,however,detected the presence ofβ-dystroglycan,even in anurans and all teleosts.A possible explanation is that in the glial end-feet,β-dystroglycan is masked in these animals,or disappeared during adaptation to the freshwater habitat.

New advance in fossil anuran study

EXCITING reports on paleontological discoveries from western Liaoning Province, northeastern China have frequently been released in the past few years. From Confuciusornis to Sinosauropteryx, from Protarchaeopteryx to the primitive mammal, Zhangheotherium, and most recently, to the possibly earliest known flower, Archaefructus liaoningensis, these founds have astounded the world, and this miracle land has drawn increasing interests of scholars all over the world. Two world-famed

大熊猫国家公园宁太管理分局辖区无尾两栖类物种多样性及壶菌病调查分析

大熊猫国家公园宁太分局辖区近年来无尾两栖类种群数量有所衰退。引起无尾两栖动物种群数量锐减的主要元凶-壶菌病,由蛙壶菌(Batrachochytrium dendrobatidis)引起。本研究在对大熊猫国家公园宁太管理分局辖区无尾两栖类进行物种多样性调查的基础上,对该辖区无尾两栖类蛙壶菌感染情况进行检测分析。调查显示,该辖区共无尾两栖类11种,分隶5科10属;PCR检测结果显示,本次采集到的52个样品均未出现蛙壶菌感染。由于此次样品数量有限,后期仍需长期、定期监测。

Acoustic characteristics of the tiger frog,Hoplobatrachus rugulosus,during the breeding season

We recorded and described the calls and acoustic characteristics of the male tiger frog,Hoplobatrachus rugulosus,in an artificial pond during mating season.Spectral and temporal call parameters,along with call intensity were analyzed.Three harmonics were distinguishable from the spectrogram.Four patterns of dominant frequency were found in calls produced late at night,i.e,3 patterns in the first harmonic（located in 500 Hz section,700 Hz section,and 800 Hz section respectively） and 1 in the second harmonic（located in 1 800 Hz section）.Call duration,call duty cycle,call intensity,and pulse rate were highly variable among different patterns of dominant frequency.These call properties could provide valuable evidence for further ecological study of this species.

我国12种无尾类的鸣叫特征参数

分析了1 2种无尾类的求偶鸣叫特征参数,包括角蟾科(Megophryidae) 2种:峨眉角蟾(Megophrysomeimontis)、高山掌突蟾(Leptolalaxalpinus) ;雨蛙科(Hylidae) 2种:华西雨蛙(Hylaannectans)、秦岭雨蛙(H .tsinlingensis) ;树蛙科(Rhacophoridae) 5种:斑腿树蛙(Rhacophorusmegacephalus)、无声囊树蛙(R .mutus) ,宝兴树蛙(R .dugritei)、经甫树蛙(R .chenfui)、锯腿小树蛙(Philautusodontotarsus) ;蛙科(Ranidae)2种:弹琴水蛙(Hylaranaadenopleura)、沼水蛙(H .guentheri) ;姬蛙科(Microhylidae) 1种:花姬蛙(Microhylapulchra)。特征参数包括:(时域)时长和(频域)基频、主能峰、共振峰等9个。与已有的描述作了对比,发现差别较小,并简单讨论了差别出现的原因。此外,对同域分布且繁殖时间重叠的两个近缘种———宝兴树蛙和经甫树蛙的鸣叫比较发现,二者声音的9个参数除了音节间隔之外,差异都极其显著(P <0 0 0 1 ,α=0 0 5 ,two tailedtest) ,它们的鸣叫有显著差异。

草坡河流域小水电开发对无尾两栖动物的影响

在江河支流上修建小型水坝正逐渐成为威胁山区生物多样性和流溪生态系统的主要因素。采用3种方法调查了四川省岷江支流草坡河流域小型水坝对当地无尾两栖动物的影响,研究结果表明:小型水坝对无尾两栖动物的生存和繁衍具有多种危害。具体表现在:(1)坝体阻碍和引水发电导致了繁殖场与栖息地减少和单一化,通过繁殖位点调查法发现上游卵团密度为下游卵团密度的40.5倍,上游的繁殖水体密度为下游的3.9倍;(2)水坝引起了下游蝌蚪数量锐减,阻断了溪流蝌蚪的迁移,通过蝌蚪数量调查法发现上游蝌蚪密度分别为下游蝌蚪密度的21倍(5月)和25.7倍(6月);(3)改变了两栖动物成体的分布格局,通过繁殖期和冬眠期的样线法调查,在水坝上游的两栖动物成体数量是水坝下游两栖动物成体数量的11.5倍。

非伤害性取样在无尾两栖类保护遗传学研究中的应用

为了改变传统的将两栖类动物处死后再从肌肉提取DNA的取样方法,采用非伤害性取样方法分别采集了虎纹蛙的血液和趾提取DNA,并与从其肌肉中提取的DNA进行了比较,结果显示:使用血液和趾提取的DNA产量与肌肉样本的DNA产量相当;随后,分别对3种方法取样的样本进行了线粒体16S rRNA和核DNA的微卫星PCR分析,结果表明:3种取样方法所获得的扩增效果相当,均能满足虎纹蛙的保护遗传学研究.因此认为,用非伤害性取样技术替代传统的肌肉取样的方法在无尾两栖类的保护遗传学研究中是切实可行的.

无尾两栖类在不同生活史阶段的栖息环境

无尾目的生活史分为卵、蝌蚪和成体3个不同的阶段,它们分别生活在迥异的环境中,形成了各自阶段的生态适应。本文综述了无尾目3个阶段的栖息环境,以繁殖模式描述卵的栖息环境,以发育序列和生态表型描述蝌蚪的栖息环境,以生活类型描述成体的栖息环境。无尾目的环境选择策略集中表现了进化的关键趋向:由水向陆的运动。利用生活史对水陆两种环境的适应优势,无尾目成功地分布到除南极洲之外的所有大陆。

两种无尾类发声器官的初步观察

应用大体解剖和组织学方法对中国林蛙(Rana chensinensis)和花背蟾蜍(Buforaddei)的发声器官进行了初步观察和比较。结果表明:中国林蛙有独立的前杓状软骨和枕声带,而花背蟾蜍则没有上述结构。花背蟾蜍的声带侧部为规则致密结缔组织构成的膜状结构,并且前端有一对肉质化的纤维小球,喉室末端有一对后膜,而中国林蛙的声带侧部由无规则致密结缔组织构成的肉质化纤维柱状结构,喉室的末端无后膜结构。前者的声带中部为一对厚度均匀的膜系结构。而后者声带中部在不同区域也存在明显的差异,中国林蛙的声囊类型为咽侧内声囊,花背蟾蜍的声囊类型为咽下内声囊。统计分析表明二者声带中部的相对长度和宽度分别存在显著性和极显著性的差异。最后,初步分析了喉部结构差异对声音产生的影响,为揭示蛙科与蟾蜍科叫声特异性提供了理论依据。

无尾两栖类抗肿瘤肽的研究进展

无尾两栖类动物所含有的生理活性物质数量巨大、种类繁多、功能复杂,是发掘天然抗肿瘤肽的巨大资源库。本文主要概述了无尾两栖动物中抗肿瘤肽的组织分布、分类、理化性质及主要作用机制,为开发两栖类动物多肽有效成分提供理论参考。