倭蛙属(无尾目∶蛙科)肩带研究

对倭蛙属(Nanorana)已知3种:高山倭蛙(Nanorana parkeri)、倭蛙(N.pleskei)和腹斑倭蛙(N.ventripunctata)的肩带作了连续切片后进行Masson染色,发现其上喙骨(epicoracoid)的融合与重叠的状况与虎纹蛙(Rana rugulosa)较相似,而与无尾目中其它物种已知的肩带形态存在较大的差异。倭蛙属和虎纹蛙等与已知肩带类型的蛙亚科其它的物种在系统进化中可能来源于不同的最近共同祖先。     

西藏色季拉山高山倭蛙的产卵地选择

高山倭蛙(Nanorana parkeri)是青藏高原的特有种和广布种.2011 ～2012年,在西藏色季拉山高山倭蛙的繁殖期内对其产卵地选择进行了调查.测量分析了产卵地及对照样方的10个环境变量后,发现高山倭蛙的产卵地与对照样方在底质、pH、水温、水深、植被盖度和有无鱼方面有显著差异,回归分析表明底质特点和pH是影响高山倭蛙产卵地选择的最主要因素.今后在该物种的保护工作中,应加强对湿地中底质为泥、pH偏中性水体的保护.     

从12S rRNA基因序列研究中国蛙科24种的进化关系

测定了中国蛙科动物24种和蟾蜍科的中华大蟾蜍线粒体12S rRNA基因长约400bp片段的序列。采用邻接法,对其数据的系统发生分析表明24种可分成3个支系：第一个支系包括棘腹蛙、合江棘蛙、棘胸蛙、大头蛙、虎纹蛙、倭蛙、泽陆蛙共７种,其中３种棘蛙组成一个单系;第二个支系由３种湍蛙,即戴云湍蛙、华南湍蛙和武夷湍蛙组成,应属于湍蛙亚科;第三支系包含余下的１４种蛙,其中５种林蛙和４种臭蛙分别组成一个单系;２种侧褶蛙先聚合后,再与弹琴水蛙聚合,２种粗上先聚合在一起,再与由林蛙组成的单系群聚合。第三支系首先与第二支系相聚,然后它们与第一支系形成姐妹群,即由蛙亚科的７个物种组成的第一支系,不与蛙亚科另１４个物种组成的第三支系直接聚合,表明第一支系的物种可能不属于蛙亚科。此外,分子证据提示把陆蛙属、大头蛙属、虎纹蛙属、棘棘属、臭蛙属、粗皮蛙属和侧褶蛙属从原来的蛙属分出有其合理性。、     

西藏两栖纲新纪录2种及缅甸树蛙描述

本文报道西藏两栖纲叉舌蛙科Dicroglossidae新纪录2种,即采于喜马拉雅山中段吉隆沟内的罗斯坦棘蛙Nanorana rostandi(Dubois,1974)和西藏东部昌都地区江达县的倭蛙Nanorana pleskei Güther,1896,前者是中国新纪录,后者是西藏自治区新纪录。首次描述了采自西藏东南部墨脱县的树蛙科缅甸树蛙Rhacophorus burmanus(Andersson,1939)。     

湍蛙亚科一新属--拟湍蛙属，兼论与近缘属的关系(两栖纲：蛙科)

对台湾产Ｒ．ｓａｕｔｅｒｉ（＝Ｐｓｅｕｄｏｒａｎａ ｓａｕｔｅｒｉ）和Ｒ．ｍｕｌｔｉｄｅｎｔｉｃｕｌａｔａ两个种和产于大陆的趾沟蛙属及其它近缘属物种进行了对比研究。由于台湾两个种的蝌蚪体腹面有吸盘,既不同于林蛙属Ｒａｎａ,也不同于趾沟蛙属Ｐｓｅｕｄｏｒａｎａ和水蛙属Ｈｙｌａｒａｎａ,而类似于湍蛙属Ａｍｏｌｏｐｓ的蝌蚪,但与后者的成体和蝌蚪又明显不同。因此,将上述台湾两个种从Ｒａｎａ中分出,建议定为     

贵州威宁发现景东臭蛙

2020年8月6日在贵州省威宁县雪山镇（27°04′09″N,104°04′44″E,海拔2 218 m）采集到6号两栖动物标本,经形态特征比较,与景东臭蛙（Odorrana jingdongensis）相似;基于线粒体16S rRNA构建臭蛙属（Odorrana）部分物种系统发育树,此次采集的臭蛙标本与景东臭蛙聚为一支,且具有较高的支持率（0.97/92,贝叶斯法/最大似然法）;基于Kimura双参数模型估算本次采集的臭蛙标本与景东模式产地标本间的遗传距离为0%,远小于臭蛙属物种间的遗传距离（1.3%～9.5%）。综合形态特征和分子系统发育比较,确定此次采集到的臭蛙标本为无尾目（Anura）蛙科（Ranidae）臭蛙属的景东臭蛙,系贵州省两栖动物分布新记录种。     

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。     

高山倭蛙消化道结构初步观察

高山倭蛙食道粘膜上皮为复层柱状上皮,且固有膜中有丰富的复泡状腺;胃贲门部粘膜上皮无杯状细胞,PAS反应显示固有膜中有深红色颗粒分布,胃体中胃腺丰富;肠分为小肠、大肠、直肠3部分.小肠和直肠上皮中杯状细胞数量多.无尾类消化道结构与海拔高度无明显相关关系.     

福建省花臭蛙复合体组成及 天目臭蛙分布新记录记述

由于没有明显的地理阻隔,闽浙丘陵地带花臭蛙复合体（Odorrana schmackeri species complex）的物种组成、分布界限、分布格局存在争议。2016年9月至10月对闽浙交界地带福建省宁德市屏南县和南平市浦城县进行野外考察、样本收集,通过扩增样本线粒体12S rRNA和16S rRNA基因并与黄岗臭蛙（O. huanggangensis）、天目臭蛙（O. tianmuii）和花臭蛙（O. schmackeri）的序列进行比对,构建系统发生关系、计算遗传距离,结合形态学鉴定和形态量度分析,对福建省花臭蛙复合体组成进行了研究。结果显示,福建省花臭蛙复合体包括黄岗臭蛙和天目臭蛙,其中黄岗臭蛙分布于武夷山山区、闽江和九龙江流域,天目臭蛙仅分布于衢江（钱塘江主要支流）的次源地——浦城县管厝乡东北部,为福建省臭蛙类分布新记录种。本研究增添了福建省两栖动物多样性并细化了黄岗臭蛙和天目臭蛙在该省分布范围的认识,但是浦城县西北端长江流域的花臭蛙复合体的物种组成仍需进一步确认。水系和流域是否影响花臭蛙复合体物种分化和分布格局以及这些近缘物种的物种形成机制有待进一步研究。     

中国无尾两栖类新记录种——朝鲜侧褶蛙北大核心CSCD

2021年9月在沈阳市蒲河湿地公园(41°41′54″N,122°52′19″E,海拔35 m)采集到3号无尾两栖类动物,经形态特征比较确认为侧褶蛙属(Pelophylax)金线侧褶蛙种组(P.plancyi species complex)的物种。基于线粒体12S rRNA和16S rRNA基因联合构建的侧褶蛙属部分物种最大似然系统发育树显示,采集到的侧褶蛙标本与朝鲜侧褶蛙(P.chosenicus)聚为一支,且具有较高的支持率(0.95)。综合形态和系统发育比较,确定采集到的标本为无尾目(Anura)蛙科(Ranidae)侧褶蛙属的朝鲜侧褶蛙,系中国两栖动物分布新记录种。     

Comparative anatomy and development of pectoral and pelvic girdles in hylid anurans

The development of the tetrapod pectoral and pelvic girdles is intimately linked to the proximal segments of the fore‐ and hindlimbs. Most studies on girdles are osteological and provide little information about soft elements such as muscles and tendons. Moreover, there are few comparative developmental studies. Comparative data gleaned from cleared‐and‐stained whole mounts and serial histological sections of 10 species of hylid frogs are presented here. Adult skeletal morphology, along with bones, muscles, and connective tissue of both girdles and their association with the proximal portions of the anuran fore‐ and hindlimbs are described. The data suggest that any similarity could be attributable to the constraints of their ball‐and‐socket joints, including incorporation of the girdle and stylopodium into a single developmental module. An ancestral state reconstruction of key structures and developmental episodes reveals that several development events occur at similar stages in different species, thereby preventing heterochronic changes. The medial contact of the halves of the pectoral girdle coincides with the emergence of the forelimbs from the branchial chamber and with the total differentiation of the linkage between the axial skeleton and the girdles. The data suggest that morphogenic activity in the anterior dorsal body region is greater than in the posterior one, reflecting the evolutionary sequence of the development of the two girdles in ancient tetrapods. The data also document the profound differences in the anatomy and development of the pectoral and pelvic girdles, supporting the proposal that the pectoral and pelvic girdles are not serially homologous, as was long presumed.     

Functional analysis of frog pectoral girdles. The epicoracoid cartilages

Two types of pectoral girdles occur among frogs. Arciferal girdles have overlapping epicoracoid cartilages; in firmisternal girdles the epicoracoid cartilages are fused along the ventral midline. Cineradiographic experiments of jumping frogs show that the epicoracoid cartilages of arciferal girdles move relative to each other at the time of landing. Recordings of landings on a force platform reveal that the pectoral girdle of frogs is loaded compressively through the glenoid. This loading regime coupled with differential mobility between firmisternal and arciferal girdles results in differences in stress distribution in the two girdles during landing. The patterns of stress distribution suggest that variation seen among frogs in other aspects of pectoral morphology in addition to the condition of the epicoracoid cartilages may be best understood when analysed from a biomechanical perspective.     

How can ontogeny help us to understand the morphology of anuran pectoral girdle?

The ontogenetic development of the pectoral girdle in seven anuran species (Xenopus laevis, Discoglossus pictus, Bombina bombina, Bombina variegata, Pelobates fuscus, Bufo bufo and Rana dalmatina) was studied using cleared and stained specimens. The epicoracoid cartilage was found to develop in two different ways resulting in an arciferal or firmisternal type of the pectoral girdle. In the arciferal one, the epicoracoid originates from a medial prolongation of the procoracoid cartilage and broadly overlaps its counter part during further development. In the firmisternal pectoral girdle, the epicoracoids are formed by the widened cartilaginous medial edges of the coracoids that fuse together along the midline. Polarization of ontogenetic characters shows, that omosternum evolves inside Anura, and the type of sternum occurring in basal Anura seems to be an apomorphy of all Batrachia. The sternal elements have a single or paired rudiment, their development is connected with M. rectus abdominis or a zonal area and they remain cartilaginous or ossify during postmetamorphic development. An occurrence of omosternum in Barbourula busuangensis was described for the first time.     

On the serial homology of the pectoral and pelvic girdles of tetrapods

While fore‐ and hindlimbs are commonly assumed to be serially homologous, the serial homology of the pectoral and pelvic girdles is more ambiguous. We investigate the degree to which a common history, developmental program, and gene network are shared between the girdles relative to the rest of the appendicular skeleton. Paleontological data indicate that pectoral appendages arose millions of years before pelvic appendages. Recent embryological and genetic data suggest that the anatomical similarity between the fore‐ and hindlimbs arose through the sequential, derived deployment of similar developmental programs and gene networks, and is therefore not due to ancestral serial homology. Much less developmental work has however been published about the girdles. Here, we provide the first detailed review of the developmental programs and gene networks of the pectoral and pelvic girdles. Our review shows that, with respect to these programs and networks, there are fewer similarities between pelvic and pectoral girdles than there are between the limbs. The available data therefore support recent hypotheses that the anatomical similarities between the fore‐ and hindlimbs arose during the fin‐to‐limb transition through the derived co‐option of similar developmental mechanisms, while the phylogenetically older pectoral and pelvic girdles have remained more distinct since their evolutionary origin.     

The evolution of paired fins

Summary The Archipterygium is Gegenbaur’s most lasting contribution to the study of vertebrate limb evolution. This transformational hypothesis of gill arches to limb girdles, rays to fins, and proposal of a vertebrate fin-limb groundplan, is generally treated as a flawed alternative to the more widely accepted lateral fin-fold hypothesis of vertebrate limb evolution. When compared to the phylogenetic distribution and diversity of fins and limbs, both hypotheses fail. Dermal skeletal lateral folds, spines and keels originate repeatedly in vertebrate evolution, but paired fins with girdles originate at pectoral level and are anteroposteriorly restricted. Pelvic fins emerge later in phylogeny; pectoral and pelvic appendages primitively differ. Endoskeletal girdles never exhibit characteristics of gill arches. The emergent sequence of paired fin evolution depends upon phylogenetic hypotheses within which extant agnathan interrelationships are uncertain; positions of jawless fossil fish along the gnathostome stem are insecure; the fossil data set is patchy. However, certain features of the data set are robust. This has prompted a reconsideration of Gegenbaur’s hypothesized arch-girdle relationship, and an iterative homology between scapulocoracoid and extrabranchial cartilages is suggested. No transformation of arch to girdle is necessarily implied, but some signal of developmental relatedness is predicted.     

广西早泥盆世一新型胴甲鱼化石并初步探讨其系统分类位置

本文描述的胴甲鱼化石标本,采自广西象州大乐早泥盆世地层.化石系内、外模,但保存非常完整,包括自然连接的头部、躯干、胸鳍及躯甲后的尾部.头甲、躯甲的特征较为接近星鳞鱼 (Asterolepis) 的特征,而某些特征又与云南鱼 (Yunnanolepis) 类似.胸鳍分为近节和远节,鳍片排列近似欧洲的翼甲鱼 (Pterichthyodes) 型的胸鳍.根据头甲、躯甲及胸鳍的特征,笔者建立了一新属、新种——Liujiangolepis suni gen. et sp. nov.,代表胴甲鱼类中—新科——Liujiangolepidae fam. nov..文中对新属种的胸鳍结构和新属种在胴甲鱼类中的分类位置做了初步探讨.     

A new oligotrich (Ciliophora,Oligotrichia) from Argentina,with redefinition of Novistrombidium Song and Bradbury

A new oligotrich similar to Novistrombidium was discovered in plankton samples from an artificial tributary of the Salado River, Buenos Aires province, Argentina, in summer 2010. Propecingulum fistoleramalliei sp. n. has an obovate and anteriorly truncated body, with a conspicuous ventral furrow, is flattened ventrally, and has a prominent right apical protrusion. It temporarily attaches to the substratum by a posterior mucous thread. Rod-shaped extrusomes arranged equidistantly and insert directly above the girdle kinety. The macronucleus is globular to ellipsoidal. The contractile vacuole is located in the left, anterior quarter of the cell and the adoral zone is composed of 30–35 collar, 9–14 buccal, and two thigmotactic membranelles. The girdle kinety is dextrally spiraled and ventrally open; the ventral kinety is posterior to anterior end of the girdle kinety. The oral primordium develops posterior to the right thigmotactic membranelle and anterior the stripe of extrusomes above left, lateral portion of the girdle kinety. The SSUrDNA phylogeny confirms one more time that Novistrombidium is not monophyletic; consequently, we elevate the subgenus Propecingulum up to genus rank and redefine the genus Novistrombidium.     

Chondrogenesis and ossification of the lissamphibian pectoral girdle

Knowledge of amphibian shoulder development is requisite for further understanding of gnathostome pectoral girdle evolution. Fish and amniotes share few pectoral girdle elements, but modern amphibians exhibit a unique combination of traits that bridge the morphological gap between these two groups. I analyzed patterns of chondrogenesis, ossification, and bone histology of the pectoral girdles of two anuran species (Xenopus laevis and Bombina orientalis) and two urodele species (Ambystoma mexicanum and Desmognathus aeneus) to provide new insight into the evolution of the tetrapod pectoral girdle. Comparisons reveal the following: 1) variation in the pattern of chondrogenesis among the anuran species analyzed correlates to variation in adult pectoral girdle morphology; 2) morphologically similar pectoral skeletons do not necessarily have similar patterns of bone histology; and 3) the urodele and anuran pectoral girdles included herein share a common morphology despite differences in patterns of chondrogenesis.     

Fossil fishes from china provide first evidence of dermal pelvic girdles in osteichthyans

Background

The pectoral and pelvic girdles support paired fins and limbs, and have transformed significantly in the diversification of gnathostomes or jawed vertebrates (including osteichthyans, chondrichthyans, acanthodians and placoderms). For instance, changes in the pectoral and pelvic girdles accompanied the transition of fins to limbs as some osteichthyans (a clade that contains the vast majority of vertebrates – bony fishes and tetrapods) ventured from aquatic to terrestrial environments. The fossil record shows that the pectoral girdles of early osteichthyans (e.g., Lophosteus, Andreolepis, Psarolepis and Guiyu) retained part of the primitive gnathostome pectoral girdle condition with spines and/or other dermal components. However, very little is known about the condition of the pelvic girdle in the earliest osteichthyans. Living osteichthyans, like chondrichthyans (cartilaginous fishes), have exclusively endoskeletal pelvic girdles, while dermal pelvic girdle components (plates and/or spines) have so far been found only in some extinct placoderms and acanthodians. Consequently, whether the pectoral and pelvic girdles are primitively similar in osteichthyans cannot be adequately evaluated, and phylogeny-based inferences regarding the primitive pelvic girdle condition in osteichthyans cannot be tested against available fossil evidence.

Methodology/Principal Findings

Here we report the first discovery of spine-bearing dermal pelvic girdles in early osteichthyans, based on a new articulated specimen of Guiyu oneiros from the Late Ludlow (Silurian) Kuanti Formation, Yunnan, as well as a re-examination of the previously described holotype. We also describe disarticulated pelvic girdles of Psarolepis romeri from the Lochkovian (Early Devonian) Xitun Formation, Yunnan, which resemble the previously reported pectoral girdles in having integrated dermal and endoskeletal components with polybasal fin articulation.

Conclusions/Significance

The new findings reveal hitherto unknown similarity in pectoral and pelvic girdles among early osteichthyans, and provide critical information for studying the evolution of pelvic girdles in osteichthyans and other gnathostomes.