温度和盐度对中华多刺鱼胚胎发育过程的影响

2006年3-5月,在北京怀柔水库入库河流怀九河的西四渡河河段,采集性成熟的中华多刺鱼(Pungitius sinensis),人工干法授精获取受精卵,观察并记录受精卵的胚胎发育历程;设置温度和盐度梯度,观察温度和盐度对中华多刺鱼胚胎发育过程的影响。结果表明:北京地区的中华多刺鱼胚胎发育的起始温度(生物学零度)为4.7℃,适宜的发育水温为14.0℃-16.0℃,与中华多刺鱼繁殖盛期(4月中下旬)自然水体的水温相近;平均水温14.0℃时,中华多刺鱼完成胚胎发育约需183h;水温升至22.5℃时,胚胎的孵化率仅为22.2%;水温升至25.0℃时,受精卵不能孵化,此温度应是中华多刺鱼胚胎发育温度的上限。实验表明,北京地区中华多刺鱼的胚胎对盐度的耐受力较为有限,在与自然水体相同的盐度下(0‰)其孵化率接近100%;随着盐度的升高,孵化率降低,8‰盐度时,仅有56%的受精卵孵化;至20‰时,受精卵全部死亡,此盐度应为中华多刺鱼胚胎发育的盐度上限。     

基于多来源数据分析河南省刺鱼目新纪录种——中华多刺鱼

2015年10月,河南省鱼类资源调查队在河南省林州市进行鱼类资源普查时,采集到30尾刺鱼目Gasterosteiformes鱼类,综合采用形态学和分子系统学的方法确定其为中华多刺鱼Pungitius sinensis,为河南省新纪录种,标本保存于河南师范大学水产学院鱼类标本室。本文对该鱼的主要鉴定特征、分布区域、可能的来源、生存环境等做了初步分析。该鱼在我国北方(辽宁、黑龙江、吉林、天津、河北等省市)及韩国、日本北方均有分布,记录最南分布区域为北京市,为北京市二级保护鱼类。此次报道进一步扩大了该鱼最南端分布界限,为进一步开展该鱼的基础研究提供了重要参考资料。     

中国柳莺属分类现状

柳莺属Phylloscopus一直是中国鸟类分类学中问题最多,研究最不完善的类群。在上世纪末的10年中,新增加了12种柳莺,包括新发现的3种和亚种被提升到种地位的9种。本文回顾和介绍了我国柳莺属分类研究概况,包括四川柳莺P.sichuanensis,海南柳莺P.hainanus和峨眉柳莺P.emeiensis3个新发现种。黄腰柳莺青藏亚种P.proregulus chloronotus和甘肃亚种P.p.kansuensis,黄腹柳莺P.affinis subaffinis亚种。黄腰柳莺青藏亚种P.proregulus chloronotus和甘肃亚种和P.c.sindianus亚种,黄眉柳莺P.inormatus humei亚种等的分类地位已由亚种升为种,但黑眉柳莺P.ricketti goodsoni亚种分类地位仍存在着争议,最后提出了目前我国柳莺属分类上尚存在的一些问题。     

链蛇属的分类分布现状

对链蛇属Dinodon的分类、分布现状进行了讨论,其中草绿链蛇Dinodon gammiei和南方链蛇D. meridionale为国内新纪录,粉链蛇D. rosozonatum为越南新纪录,黄链蛇D. flavozonatum为重庆市新纪录.     

中国双皮菌属黏菌的物种及分布

双皮菌属是黏菌纲中最重要的属之一,通过标本的鉴定和复核以及文献考证等分类学研究,重新整理和报道了中国双皮菌属黏菌的物种资料,计有24种,探讨了它们的分布特征和与基质的联系,增补了一些种在中国的分布省区,对过去报道的某些种的学名和分类地位进行了更正.     

桃曲坡牙形刺属（Taoqupognathus）在澳大利亚及中国晚奥陶世的分布

Taoqupognathus为潘德尔刺类的一多分子器官属。其特征明显：单维,片状,具有不同发育程度的后缘隆起。该属仅在澳大利亚东部和中国上奥陶统分布,已知有4种,而且具有较精确的区域对比价值。形态特征的支序分析显示：在晚奥陶世中期（Eastonian),T.philipi-T.blandus-T.tumidus谱系代表了该属的主要演化趋向。Taoqupognathus属的分布表明,澳大利亚东部和中国在当时有着密切的生物地理联系。该属可能在Eastonian早期起源于新南威尔世中部地区,在中－晚Eastonian期时达到发展高潮,并已扩展到中国各板块。继而可能在Eastonian末期和Bolindian早期全部绝灭。     

中国石头花属的分类和分布

本文报道我国石头花属植物有18种(其中2新种)1变种,分隶于5组。大多分布西北、华北和东北地区,新疆是我国本属植物的分布和分化中心,种数往东递减。河北石头花、华山石头花、刺序石头花和细叶石头花为我国特有种。     

中国绒泡菌属黏菌的物种及分布

绒泡菌属是黏菌纲最大的一个属,通过标本的鉴定和复核以及文献考证等分类学研究,重新整理和报道了中国绒泡菌属黏菌的物种资料,计有93种,探讨了它们的分布特征和地理成分,一些种在中国的分布省区被增补。     

中国兔属动物的分类现状和分布

兔属 (Lepus)动物是一类广泛分布、彼此差异较小的哺乳动物 ,属于兔形目 (Lagomorpha)、兔科(Leporidae)。本文根据目前的分类现状 ,列出中国兔属种、亚种名录和分布区 ;对中国兔属动物的研究历史进行了综述 ;并针对蒙古兔、华南兔、云南兔、中亚兔和东北黑兔分类地位存在的争议进行了讨论     

近期引入三刺鱼种群的骨板和体型的现时进化

近期引入到新环境中的种群给我们提供了一个推论种群过去微进化变化的难得的机会,而这些变化曾导致了种群在历史上对新栖息地拓殖的适应。自从1967年三刺鱼(GasterosteusaculeatusL.)被有意引入到不列颠哥伦比亚的Heisholt湖后,就隔离的淡水对其完全骨板化(CP)变体的相对适合度的影响已经做过多种多样的测定。CP变体的个体在早期的样本中比较常见(占20.3%-31.7%),而在现代的样本中比较稀少(占0%-5.0%)。后者样本中骨板弱化的变体占优势,这是绝大多数淡水种群的典型情形。我估测Heisholt湖的一个流域中三刺鱼体侧骨板数目从1974年到1997年的进化速率是-0.029海尔登,这比大多数对近期引入的或隔离的三刺鱼种群的现时进化的估测要低。最后,来自于Heisholt湖的CP个体比那些作为引入源溪流中的个体明显要小。总之,对应于已建群的自然淡水种群的文献资料,在引入种群中所观察到的个体大小和体侧骨板数目的变化,意味着三刺鱼对与淡水环境中生活相关的多种挑战的适应可以快速发生。     

Phylogenetic placement of Geastrum melanocephalum and polyphyly of Geastrum triplex

Geastrum melanocephalum, originally described as Trichaster melanocephalus, is characterized by large basidiomata and an evanescent endoperidium. Although Trichaster was recently treated as a synonym of Geastrum and the specific name G. melanocephalum has often been used, it is still controversial whether Trichaster is an independent genus. Although a close affinity of G. melanocephalum and G. triplex has been suggested based on some morphological similarities, it is highly likely that G. triplex is polyphyletic because of its high morphological variability. To clarify the phylogenetic position of G. melanocephalum, it is therefore critical to evaluate the monophyly of G. triplex. This study sampled ITS, LSU, and atp6 genes from 144 specimens of Geastrales including G. melanocephalum and G. triplex from several continents. Results of phylogenetic analyses demonstrated G. melanocephalum is nested within Geastrum and is most closely related to the European and North American group of G. triplex. Morphological similarities of G. melanocephalum and European and North American G. triplex are also suggested. Based on phylogenetic and morphological evidence, we confirm Trichaster is a synonym of Geastrum, and the scientific name Geastrum melanocephalum should be accepted. Moreover, the present study revealed that taxa tentatively identified as “G. triplex” are highly polyphyletic, and a taxonomic revision of “G. triplex” is therefore needed.     

Taxonomic status and evolutionary history of the Saxicola torquata complex

We explored variation in mitochondrial ND2 gene sequences from 171 stonechats (Saxicola torquata complex) collected from 27 Eurasian and 3 African localities. We found that two widespread neighboring Eurasian subspecies of Siberian stonechat, Saxicola maura maura and S. m. stejnegeri, although very similar in appearance, are not each other’s closest relatives. Eastern Asian S. m. stejnegeri appears to have split from other Palearctic, African, and island stonechats well before differentiation occurred among the latter taxa. Our data indicate that European (S. t. rubicola), central Palearctic (S. m. maura) and eastern Palearctic (S. m. stejnegeri) are independently evolving, and could each warrant separate species status, as assumed earlier for S. rubicola, S. maura and S. torquata. However, we found three localities at which individuals from different major groups occurred. Thus, although these are likely phylogenetic species it is unclear whether they are biological species. There was little phylogeographic structure within the three major Palearctic clades, although samples from Spain might be showing incipient divergence. We maintain that the topology of a mtDNA gene tree is a valid means to discern taxonomic limits.     

FBIS: A regional DNA barcode archival & analysis system for Indian fishes

DNA barcode is a new tool for taxon recognition and classification of biological organisms based on sequence of a fragment of mitochondrial gene, cytochrome c oxidase I (COI). In view of the growing importance of the fish DNA barcoding for species identification, molecular taxonomy and fish diversity conservation, we developed a Fish Barcode Information System (FBIS) for Indian fishes, which will serve as a regional DNA barcode archival and analysis system. The database presently contains 2334 sequence records of COI gene for 472 aquatic species belonging to 39 orders and 136 families, collected from available published data sources. Additionally, it contains information on phenotype, distribution and IUCN Red List status of fishes. The web version of FBIS was designed using MySQL, Perl and PHP under Linux operating platform to (a) store and manage the acquisition (b) analyze and explore DNA barcode records (c) identify species and estimate genetic divergence. FBIS has also been integrated with appropriate tools for retrieving and viewing information about the database statistics and taxonomy. It is expected that FBIS would be useful as a potent information system in fish molecular taxonomy, phylogeny and genomics. AVAILABILITY: The database is available for free at http://mail.nbfgr.res.in/fbis/     

Cranial morphometrics and mitochondrial DNA sequences distinguish cryptic species of the longface emperor (Lethrinus olivaceus), an emblematic fish of Indo-West Pacific coral reefs

Range-wide morphometric variability (cranial measurements) and genetic variability (nucleotide sequences of the cytochrome b gene) were investigated in the longface emperor, Lethrinus olivaceus (Lethrinidae), an emblematic large predatory fish of Indo-West Pacific coral reefs. Two cranial morphotypes were observed, one present from the Indian Ocean to the Coral Triangle and the other one, from the Coral Triangle to the western Central Pacific. The two morphotypes are concordant with reciprocally monophyletic mitochondrial lineages separated by 9.5% net nucleotide distance. These results suggest an old evolutionary history for L. olivaceus, which consists of two distinct species (Lethrinus sp. A in the Indian Ocean and Coral Triangle, Lethrinus sp. B in the western Pacific Ocean), whose distribution ranges meet or overlap in the eastern part of the Coral Triangle, in Taiwan and in West Papua. Lethrinus sp. A comprises two distinct mitochondrial lineages separated by 1.7% net nucleotide distance, one exclusive to the populations from the Indian Ocean, the other exclusive to Coral Triangle populations. The latter observation might be explained by vicariance, whereby the two lineages have been isolated from one another on either side of the Sunda Shelf because of low sea level in the Pleistocene. To clarify the nomenclature of this species complex, we recommend sequencing a fragment of the cytochrome b gene of the holotypes of L. olivaceus and of its first junior synonyms L. rostratus and L. waigiensis.     

Javan mongoose or small Indian mongoose–who is where?

The Javan mongoose Urva javanica and the small Indian mongoose Urva auropunctata have been recently shown not to be conspecific. However, the limits of their respective distribution ranges have not been fully defined. In particular, Chinese populations were not attributed to either species using molecular data. Furthermore, the small mongooses found on Hong Kong Island (discovered at the end of the 1980s) were not clearly attributed to U. auropunctata or U. javanica, nor their status (native or introduced) established. The main aims of this study were to: (1) investigate the intraspecific genetic diversity and structure within these two species; and (2) clarify the distribution limits of U. auropunctata and U. javanica, and in particular, to identify Chinese populations, and determine which species occurs on Hong Kong Island (and whether they are native or introduced). The analyses of one nuclear and three mitochondrial genes confirmed the separation of U. javanica and U. auropunctata, and showed that the populations from southern China and Hong Kong Island belong to U. javanica. The intraspecific geographical structure of the two species is clarified, and the taxonomic implications are discussed. In particular, we found a strong divergence of Javan individuals of U. javanica, which should be considered a separate subspecies.