基于线粒体12S和16S rRNA基因部分序列的角蟾亚科部分属种的系统发育关系

测定了角蟾亚科2属8种(亚种)和外群3种的线粒体12S和16S rRNA基因部分DNA序列,比对后序列长共949bp,其中变异位点数320,简约位点数206。邻接法和最大简约法分析的系统关系树一致表明内群为一单系群,其中腺角蟾首先与其他物种分开;沙坪角蟾与宽头短腿蟾聚为一支;余下的5种(亚种)角蟾组成一支,其中小角蟾短肢亚种的广西种群和香港种群聚为一亚支,另一亚支包括峨眉角蟾、小角蟾指名亚种、尾凸角蟾和重庆武隆的角蟾种,后两种角蟾进化关系最近。本结果支持短肢角蟾为有效种,同时提示腺角蟾、沙坪角蟾与宽头短腿蟾可能隶属3个不同的亚属或属。     

角蟾亚科3物种皮肤的组织学观察

应用石蜡切片和H.E染色技术,对角蟾亚科3个属的代表物种:短肢异角蟾(Xenophrys brachykolos)、宽头短腿蟾(Brachytarsophrys carinense)和小口拟角蟾(Ophryophryne microstoma)的皮肤进行了组织学观察及参数测量比较。分别取头背、体背和体腹3个部位的皮肤进行观察。结果表明,3物种的皮肤基本结构相似,均由表皮和真皮组成,真皮包括疏松层和致密层,疏松层中有大量腺体分布,包括黏液腺和颗粒腺2种。皮肤厚度、各组织层相对厚度以及腺体密度之间存在种间差异和部位差异。在宽头短腿蟾背部皮肤中,发现了与尖吻山角蟾(Megophrys nasuta)皮肤中一种片层状、H.E染色呈蓝色的皮肤真皮骨化结构(osteoderms)很相似的结构;短肢异角蟾皮肤中有明显的钙化层结构,小口拟角蟾皮肤钙化程度较弱。皮肤的骨化和钙化可能具有防止水分流失,抵御干燥的功能。2种内骨骼在角蟾亚科中同时存在,为探讨两栖动物皮肤内骨骼的进化提供了重要的研究基础。     

湖北省两栖动物新纪录——尾突角蟾

2003年7月,在湖北后河国家级自然保护区采集到一批两栖动物标本,经鉴定其中一只为尾突角蟾(Megophrys caudoprocta),系湖北省新纪录种,分类上隶属于两栖纲无尾目角蟾科角蟾属。     

角蟾科一新亚种——炳灵角蟾梵净山亚种

报道了角蟾科一新亚种,该亚种具角蟾属特征,与峨眉角蟾种组中的炳灵角蟾(Megophrysbinlingensis)形态特征最为相近,但与该组成员又有明显区别,被命名为炳灵角蟾梵净山亚种(M.b.fanjingmontis subsp.nov.)。本亚种主要鉴别特征为犁骨棱较弱,后端无犁骨齿,上颌有细齿;第一、二指上婚刺细密,趾侧缘膜窄;体腹面斑少,两侧黑褐色长形斑明显;体型较大,雄性头体长大于60.00 mm;趾间具1/3蹼。     

中国角蟾科动物系统发育研究中的几个问题

根据外部形态、核型以技精子形态等特征,角蟾科分布于中国的角蟾属（Megophrys）较之拟髭蟾属（Leptobrachium）是更为原始的类群,角蟾科动物中拟角蟾属（Ophryophryne）与角蟾属亲缘关系较近,短腿蟾属（Brachytarsophrys）是较为原始的类群,且应为一无效属,无耳蟾属（Atympanophrys）应为一有效属。角蟾属可以分为两个种组,其是峨嵋角蟾种组比较进化,白颌大角蟾种组比较原始。     

中国浙江省发现异角蟾属一新种（两栖纲：角蟾科）

根据形态特征比较,浙江丽水所采集的异角蟾标本应属一新种——丽水异角蟾Xenophrys lishuiensis Wang,LiuJiang,sp.nov.。正模标本:WYF00164,雄性成体,2016年5月20日采于浙江省丽水市莲都区葑垟林场附近(28°11′51.72″N,119°49′2.28″E,海拔1 100 m);配模标本:WYF00169,雌性成体;副模标本:12♂♂(WYF00165~WYF00168,WYF00171~WYF00178),2♀♀(WYF00170和WYF11011),均与正模同时、同地采集。正模和配模标本,以及8号副模标本(WYF00165~WYF00168,WYF00171~WYF00173,WYF11011)保存于中国科学院成都生物研究所两栖爬行动物标本馆,其余6号副模标本(WYF00170,WYF00174~WYF00178)保存于浙江自然博物馆。丽水异角蟾主要鉴别特征为:1)体型小,雄性体长30.7~34.7 mm,雌性体长36.9~40.4 mm;2)头长略大于头宽;3)无犁骨棱,无犁骨齿;4)舌游离端无缺刻;5)掌突2个;6)胫长不及体长之半;7)趾间无蹼,趾侧无缘膜;8)背部具"X"形斑块,或"X"形斑中间断开,色斑粗,边缘清晰且镶浅色边;9)头背三角形斑与体背斑块不相连;10)雄性肩部具不显著的浅色半圆斑;11)雄性第一、二指背面具婚垫和极小而密集的婚刺,第二指婚刺较少。依据线粒体基因16S r RNA共397 bp序列以贝叶斯法构建异角蟾属14个物种间的系统发育关系。包括新种丽水异角蟾在内的10个异角蟾属物种,以高支持率(后验概率98%)形成一个单系(支系B),其中,该种3个个体以高支持率(后验概率100%)形成一个单独的支系,与其近缘种淡肩异角蟾(X.boettgeri)之间的遗传距离为3.9%,大于同属部分物种间遗传距离。     

中国湖南角蟾科一新种——桑植角蟾

对采集于湖南桑植县天平山的角蟾标本(CIB200078)与同域分布的相近种尾突角蟾(Megophrys caudoprocta Shen,1994)标本及其他相近种标本比较后发现,该角蟾标本在形态上明显不同于其他物种。其形态特征与尾突角蟾相比:体形小,体长54.7mm;上眼脸外缘三角形突起小;体腹面后部有斑点;犁骨棱弱,末端不膨大,也无犁骨齿;雄性第一、二指背面黑婚刺相对较大,有声囊。与棘指角蟾相比:肛孔上方有一个向后突出的尾突,腹面观可见;雄性第一、二指背面黑婚刺相对较小而密。故将其订为新种:桑植角蟾Megophrys sangzhiensis sp.nov.。     

中国角蟾属一新种(两栖纲:锄足蟾科)

采自贵州省水城县凤凰乡的一种大形角蟾,因其外部形态与角蟾属Ｍｅｇｏｐｈｒｙｓ已知种有一些特异之处,尤其是鼓膜显露;上颌内缘无栉齿状突;头后部有由痣粒组成的“Ｖ”形棕褐色斑;背部痣纹呈“＊”形;有犁骨棱;雄性无声囊等特征与大花角蟾Ｍ．ｇｉｇａｎｔｉｃａ明显不同。据此认为该角蟾为一新种,定名水城角蟾Ｍｅｇｏｐｈｒｙｓ ｓｈｕｉｃｈｅｎｇｅｎｓｉｓ Ｔｉａｎ,Ｇｕ ｅｔ Ｓｕｎ,ｓｐ．ｎｏｖ．。     

广东省角蟾科新纪录--莽山角蟾

1999年及2001年先后在广东省始兴县车八岭国家自然保护区采得角蟾科角蟾属标本,经与角蟾属已知种对比,特别是与相似种白颌大角蟾M．lateralis(Anderson)对比,其差异明显,鉴定为广东省新记录——莽山角蟾M．mangshanensis。     

中国角蟾亚科精子形态比较及分类学讨论(两栖纲：锄足蟾科)

应用光镜和电镜对角蟾亚科短腿蟾属,拟角蟾属和角蟾属3属18种精子的形态结构进行观察和比较。并通过计算机对其各部位长度进行了测量和计算,结果表明角蟾亚科精子的共同特征是：精子主要由头和尾两部分组成,头部呈螺旋状,尾部为波状或弯曲状,但精子的量度和头部形状在属间和种间存在明显差别,角蟾亚科的精子可分为3类,该亚科精子形态的差异与成体形态学研究结果基本相吻合,精子形态的差异可为该亚科属,种的划分,亲缘关系研究提供新依据。     

Bony-tailed tadpoles: the development of supernumerary caudal vertebrae in larval megophryids (Anura)

The axial skeleton in most anuran families consists of or=7). Tadpoles from each genus are typically found in streams, where their extended caudal skeleton anchors muscles that facilitate tadpoles wiggling between plant debris and rocks or even burrowing into the stream bed. The extra centra of megophryids ossify differently in each genus. In Leptobrachella and Ophryophryne, the caudal centra ossify around the entire notochord, whereas in Megophrys and Xenophrys each develops from dorsal and ventral pairs of ossifications that expand to meet each other. The evolutionary loss of caudal centra, an apomorphic anuran trait, is reversed in larval megophryids and confirms that the machinery for caudal vertebral development has been retained in some modern anurans. A likely driving force in the reappearance of the trait in megophryids is the selective pressure associated with a riparian lifestyle.     

A New Species of the Genus Xenophrys(Amphibia: Anura: Megophryidae) from Libo County,Guizhou, China

A new species of the genus Xenophrys is described from a karst cave environment of Libo County, Guizhou Province, Southern China. The new species, Xenophrys liboensis sp. nov., is distinguished from its congeners by a combination of the following characters: 1) tympanum distinct; 2) vomerine teeth present; 3) the length of lower arm and hand larger than the half of snout-vent; 4) heels overlapped slightly when the flexed legs are held at right angles to the body axis; 5) toe tips with rudimentary webs and without grooves; 6) dermal fringes moderate; 7) tubercles on the dorsum forming an X-shaped weak ridge; 8) horn-like tubercle at the edge of the upper eyelid distinct; 9) color of the iris in life is brown. In Bayesian phylogenetic analysis of 22 species of Xenophrys, all the individuals of X. liboensis sp. nov. clustered into a monophyletic clade with high posterior probabilities. In addition, the ranges of genetic divergences of X. liboensis sp. nov. with other species were interspecific rather than intraspecific. Based on the above evidences, we consider that X. liboensis sp. nov. is a valid species in Xenophrys.     

基于16S rRNA序列的角蟾科部分属间系统关系

采用最大似然法(ML法)、最大简约法(MP法)、邻接法(NJ法)对来自角蟾科Megophryidae(Anura)8属17种及外群2种共25条400bp左右的线粒体16S rRNA序列进行系统发育关系分析。结果表明,用于分析的所有角蟾科物种形成两大支,第一支包括Megophrys,Brachytarsophrys和Atympanophrys,第二支包括Leptobrachium,Leptolalax,Scutiger,Oreolalax和Vibrissaphora。支持将角蟾科划分为两大类群,即第一支属于Megophryini族．第二支属于Leptobrachiini族。根据分子钟模型初步推测两类群问的分歧时间大致为14．2～18．7百万年前。在Megophryini族中,基因树的拓扑结构不支持Atympanophrys建立后的Megophrys为单系;而在Leptobrachiini族中,Leptolalax为一有效属,其系统发生较早。     

贵州赤水发现峨眉角蟾

2019年5月18和19日,在贵州赤水桫椤国家级自然保护区金沙沟片区(28°26′12″N,105°59′52″E海拔465m)采集到8只两栖动物标本。形态上,这些标本与模式产地的峨眉角蟾(Megophrys omeimontis)相近。基于528 bp的16S rRNA基因片段构建最大似然系统发育树表明,本次采集的8只标本与峨眉角蟾模式产地标本聚在一起,其遗传距离远小于角蟾属其他物种之间的遗传距离。因此,结合分子系统学分析及形态学比较,确认这些标本为无尾目(Anura)角蟾科(Megophryidae)角蟾属的峨眉角蟾,系贵州省两栖动物分布新记录种。     

Morphology,Molecular Genetics,and Bioacoustics Support Two New Sympatric Xenophrys Toads (Amphibia: Anura: Megophryidae) in Southeast China

Given their recent worldwide declines and extinctions, characterization of species-level diversity is of critical importance for large-scale biodiversity assessments and conservation of amphibians. This task is made difficult by the existence of cryptic species complexes, species groups comprising closely related and morphologically analogous species. The combination of morphology, genetic, and bioacoustic analyses permits robust and accurate species identification. Using these methods, we discovered two undescribed Xenophrys species, namely Xenophrys lini sp. nov. and Xenophrys cheni sp. nov. from the middle range of Luoxiao Mountains, southeast China. These two new species can be reliably distinguished from other known congeners by morphological and morphometric differences, distinctness in male advertisement calls, and substantial genetic distances (>3.6%) based on the mitochondrial 16s and 12s rRNA genes. The two new species, together with X. jinggangensis, are sympatric in the middle range of Luoxiao Mountains but may be isolated altitudinally and ecologically. Our study provides a first step to help resolve previously unrecognized cryptic biodiversity and provides insights into the understanding of Xenophrys diversification in the mountain complexes of southeast China.     

贵州省发现短肢角蟾

2012年6月,在梵净山国家级自然保护区附近的松桃县一村庄采到雄性角蟾标本1号,经鉴定为短肢角蟾(Megophrys brachykolos Inger and Romer),系贵州省两栖动物新纪录。     

A New Species of the Asian Toad Genus Megophrys sensu lato(Amphibia: Anura: Megophryidae) from Guizhou Province,China

We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent lineage in Megophrys(Panophrys) clade. The new species is distinguished from its congeners by a combination of the following morphological characteristics:(1) small body size with SVL 38.8 mm in male and SVL 42.3 mm in female;(2) vomerine teeth absent;(3) tongue not notched behind;(4) a small horn-like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two metacarpal tubercles in hand;(7) relative finger lengths: II I V III;(8) toes with rudimentary webbing at bases;(9) heels overlapping when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.     

5种江西省两栖动物新纪录

2010～2012年,在江西省山区开展两栖爬行动物调查,共发现江西省两栖动物新纪录5种:即黄山角蟾(Xenophrys huangshanensis)、莽山角蟾(X.mangshanensis)、崇安湍蛙(Amolops chunganensis、凹耳臭蛙(Odorrana tormota)和宜章臭蛙(O.yizhangensis).