噪音环境下花臭蛙求偶鸣声特征分析

2012年7月份,在黄山浮溪地区利用超声录音设备录制并分析了繁殖季节雄性花臭蛙(Odorrana schmackeri)个体的求偶鸣声。观察发现花臭蛙繁殖活动主要集中在7月中旬,繁殖高峰期活动无昼夜规律,全天均可见求偶鸣叫及抱对产卵等行为,并且多在浅水滩处活动。花臭蛙鸣声根据音节数和声谱特征可分为4种类型:即单音节音、婴儿音、双音节音和多音节断奏音,其中,单音节音、双音节音和婴儿音较为常见。利用Selena软件给出4种声音的语图以及各自对应的能谱图,利用Sound Analysis pro v1.2对单音节音、双音节音和婴儿音的鸣声特征参数进行定量分析,分析的声音参数包括鸣叫持续时间、音节数、音节持续时间、音节间隔、主频、脉冲率等。结果表明,花臭蛙鸣声的主频范围为1.8~4.5 k Hz(n=65)。鸣声不包括超声组分,主频峰值(3.1±0.7)k Hz,与前人电生理实验所得花臭蛙听觉敏感峰值一致,说明花臭蛙主要在这一频段进行通讯。对3种常见鸣叫音声音参数的单因素方差分析结果表明,双音节音与单音节音和婴儿音在声音持续时间上存在显著性差异(P0.01),双音节音和单音节音在第二谐波声强上也具有显著性差异(P=0.01)。花臭蛙的双音节音在3种常见鸣叫音中具有最长的持续时间,为(99.5±8.4)ms,故推测,双音节音为花臭蛙繁殖期主要求偶鸣声,并通过其鸣声时长的变化来体现自身品质的好坏。     

湖北省两栖类一新纪录——大绿臭蛙

2009年8～9月及2010年7月,在湖北省宜昌市高家堰镇采集两栖类标本,其中,部分臭蛙标本被鉴定为大绿臭蛙(Odorrana graminea),属湖北省新纪录。要确定中国大绿臭蛙各居群的关系、澄清其分类问题,有必要进行适度的资源考察和深入的系统地理学研究。     

Auditory response characteristics of the piebald odorous frog and their implications

The piebald odorous frog (Odorrana schmackeri), the large odorous frog (Odorrana livida) and the concave-eared torrent frog (Amolops tormotus) are sympatric species living near the same torrent streams in the vicinity of Mt. Huangshan, China. A recent study demonstrated that A. tormotus can use sound signals involving ultrasonic components for communication in a noisy environment, and another sympatric species, O. livida, can also perceive ultrasonic sound. Here we report data on the hearing range of O. schmackeri by studying auditory evoked potentials and single-unit data from the torus semicircularis. This frog exhibits its two most sensitive peaks at 2 kHz and 3.5–4.0 kHz with thresholds <42 dB SPL, with an upper frequency limit of hearing at 8.5 kHz with threshold of 87 dB SPL. The upper limit is much lower than those of O. livida and A. tormotus, at 22 and 34 kHz, respectively. It suggests that sympatric species may respond differently to similar environmental selection pressures sculpting auditory communication systems.     

贵州悬钩子属(蔷薇科)一新种--务川悬钩子

报道了贵州省务川县发现的悬钩子属Rubus（蔷薇科Rosaceae）一新种——务川悬钩子R．wuchuanensis S．Z．He。该种在体态上与锯叶悬钩子R．wuzhianus L．T．Lu＆Boufford相近,区别在于其叶片卵状披针形,边缘疏生小锯齿;叶柄较短,长0．7-1cm;花序为顶生稀疏总状花序,具花8-10朵：花梗长3．55cm;花瓣先端具骤突尖头。     

我国臭蛙属(两栖纲:蛙科)的系统发育

为探讨臭蛙属的种间亲缘关系与其起源和分化,采用PAUP3．1软件对我国的16种臭蛙的29项分类性状进行系统发育关系的研究。结果表明,臭蛙属物种形成1个单系群,可以划分为4个种组;表明了臭蛙属中国物种间的亲缘关系;无指盘臭蛙和云南臭蛙是本属中最原始的物种,鸭嘴臭蛙等是较特化的物种;原始臭蛙可能起源于横断山区和云南西部高原,贵州高原可能是臭蛙的分化中心;各种组内相近种的地理替代呈南北方向更替,而种组间则呈东西方向更替;原始物种多分布于中国西南部,较进化或特化物种多分布于中国东部和东南部及海岛上;其种组亲缘关系与地理分布格局显示出一致性。     

Identification and bioactivity evaluation of a novel bradykinin inhibitory peptide from the skin secretion of Chinese large odorous frog,Odorrana livida

A novel peptide was isolated from the skin secretion of Chinese large odorous frog, Odorrana livida, and was named as Rana‐BI. The cDNA sequencing was obtained by ‘shotgun’ cloning. The amino acid sequence of the mature peptide was identified as Gly‐Leu‐Leu‐Ser‐Gly‐Lys‐Ser‐Val‐Lys‐Gly‐Ser‐Ile‐OH by automated Edman degradation, and the molecular weight of the peptide was confirmed to be 1144.68 Da by MALDI‐TOF and liquid chromatography/MS. Subsequently, the bioactivity of synthetic peptide was evaluated by smooth muscle assay using isolated rat bladder preparation. It was demonstrated that Rana‐BI inhibited the contraction of rat bladder induced by bradykinin. Comparing with other peptides by searching from database, the primary structure of Rana‐BI showed high similarity with that of an antimicrobial peptide of Rana family (12/12 residues). These data revealed a novel biological function of this peptide. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.     

Ultrasonic signalling by a Bornean frog

Among anuran amphibians, only two species, Odorrana tormota and Huia cavitympanum, are known to possess recessed tympanic membranes. Odorrana tormota is the first non-mammalian vertebrate demonstrated to communicate with ultrasonic frequencies (above 20 kHz), and the frogs' sunken tympana are hypothesized to play a key role in their high-frequency hearing sensitivity. Here we present the first data on the vocalizations of H. cavitympanum. We found that this species emits extraordinarily high-frequency calls, a portion of which are comprised entirely of ultrasound. This represents the first documentation of an anuran species producing purely ultrasonic signals. In addition, the vocal repertoire of H. cavitympanum is highly variable in frequency modulation pattern and spectral composition. The frogs' use of vocal signals with a wide range of dominant frequencies may be a strategy to maximize acoustic energy transmission to both nearby and distant receivers. The convergence of these species' call characteristics should stimulate additional, phylogenetically based studies of other lower vertebrates to provide new insight into the mechanistic and evolutionary foundations of high-frequency hearing in all vertebrate forms.     

Amphibian tachykinin precursor

The precursor of amphibian tachykinin has not been found although more than 30 tachykinins have been isolated from amphibians since 1964. In this report, two tachykinin-like peptides are identified from the skin secretions of the frog, Odorrana grahami. Their amino acid sequences are DDTEDLANKFIGLM-NH(2) (named tachykinin OG1) and DDASDRAKKFYGLM-NH(2) that is the same with ranamargarin found in Rana margaretae, respectively, with a conserved FXGLM-NH(2) C-terminal consensus motif. By cDNA cloning, their precursors were screened from the skin cDNA library of O. grahami. The precursors are composed of 61 amino acid (aa) residues including a signal peptide followed by an acidic spacer peptide and one copy of mature tachykinin-like peptide. Their overall structure is different from structures of other tachykinin precursors such as human protachykinin 1 precursor containing 143 aa including one copy of substance P (SP) and neurokinin A (NKA), and ascidian tachykinin 1 precursor containing 164 aa including two copies of tachykinin-like peptides. The current results demonstrate that the biosynthesis mode of tachykinins in amphibians is different from other animals.     

Host defense peptides in skin secretions of Odorrana tiannanensis: Proof for other survival strategy of the frog than merely anti-microbial

Genus Odorrana, among all amphibians studied, is generally reported to have the most abundant and diversified anti-microbial peptides even from a single individual frog. In our previous work, 46 cDNA sequences encoding precursors of 22 different anti-microbial peptides (AMPs) were characterized from the skin of frog, Odorrana tiannanensis. In this work, we reported the purification of three AMPs from skin secretions of O. tiannanensis. Their amino acid sequences matched well with the sequences deduced from cDNAs and they were designated as Odorranain-C7HSa, Brevinin-1-OT2 and Odorranain-G-OT, respectively. Furthermore, we selected to analyze the four most structurally diversified sequences among the 22 AMPs that are significantly different from all reported AMPs. By structural characterization, three of them were designated as pleurain-E-OT, odorranain-G-OT, odorranain-A-OT, belonging to AMP families already identified. The forth one with a unique 14-mer sequence of AILTTLANWARKFLa and C-terminal amidation represents the prototypes of a new class of amphibian AMP, and thereby named tiannanensin. Such broad diversity in sequences and structures are consistent with other species in Genus Odorrana. Multi-functions of the synthesized four special AMPs were screened, including anti-microbial, antioxidant, cytotoxic and hemolytic activities. The results suggest that these AMPs may employ sophisticated mechanisms of action in host defense in addition to anti-microbial, although their precise contribution to host defense still seems unclear.