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1.
The evolution of the coleopteran suborder Adephaga is discussed based on a robust phylogenetic background. Analyses of morphological characters yield results nearly identical to recent molecular phylogenies, with the highly specialized Gyrinidae placed as sister to the remaining families, which form two large, reciprocally monophyletic subunits, the aquatic Haliplidae + Dytiscoidea (Meruidae, Noteridae, Aspidytidae, Amphizoidae, Hygrobiidae, Dytiscidae) on one hand, and the terrestrial Geadephaga (Trachypachidae + Carabidae) on the other. The ancestral habitat of Adephaga, either terrestrial or aquatic, remains ambiguous. The former option would imply two or three independent invasions of aquatic habitats, with very different structural adaptations in larvae of Gyrinidae, Haliplidae and Dytiscoidea.  相似文献   

2.
A supertree for Adephaga was reconstructed based on 43 independent source trees – including cladograms based on Hennigian and numerical cladistic analyses of morphological and molecular data – and on a backbone taxonomy. To overcome problems associated with both the size of the group and the comparative paucity of available information, our analysis was made at the genus level (requiring synonymizing taxa at different levels across the trees) and used Safe Taxonomic Reduction to remove especially poorly known species. The final supertree contained 401 genera, making it the most comprehensive phylogenetic estimate yet published for the group. Interrelationships among the families are well resolved. Gyrinidae constitute the basal sister group, Haliplidae appear as the sister taxon of Geadephaga+Dytiscoidea, Noteridae are the sister group of the remaining Dytiscoidea, Amphizoidae and Aspidytidae are sister groups, and Hygrobiidae forms a clade with Dytiscidae. Resolution within the species-rich Dytiscidae is generally high, but some relations remain unclear. Trachypachidae are the sister group of Carabidae (including Rhysodidae), in contrast to a proposed sister-group relationship between Trachypachidae and Dytiscoidea. Carabidae are only monophyletic with the inclusion of a non-monophyletic Rhysodidae, but resolution within this megadiverse group is generally low. Non-monophyly of Rhysodidae is extremely unlikely from a morphological point of view, and this group remains the greatest enigma in adephagan systematics. Despite the insights gained, our findings highlight that a combined and coordinated effort of morphologists and molecular systematists is still required to expand the phylogenetic database to enable a solid and comprehensive reconstruction of adephagan phylogeny. See also Supplementary material in the online edition at doi:10.1016/j.ode.2006.05.003  相似文献   

3.
A phylogenetic analysis of Adephaga is presented. It is based on 148 morphological characters of adults and larvae and focussed on a placement of the recently described Meruidae, and the genus‐level phylogeny of the smaller aquatic families Gyrinidae, Haliplidae and Noteridae. We found a sister group relationship between Gyrinidae and the remaining adephagan families, as was found in previous studies using morphology. Haliplidae are either the sister group of Dytiscoidea or the sister group of a clade comprising Geadephaga and the dytiscoid families. Trachypachidae was placed as the sister group of the rhysodid‐carabid clade or of Dytiscoidea. The monophyly of Dytiscoidea including Meru is well supported. Autapomorphies are the extensive metathoracic intercoxal septum, the origin of the metafurca from this structure, the loss of Mm. furcacoxalis anterior and posterior, and possibly the presence of an elongated subcubital setal binding patch. Meruidae was placed as sister group of the Noteridae. Synapomorphies are the absence of the transverse ridge of the metaventrite, the fusion of abdominal segments III and IV, the shape of the strongly asymmetric parameres, and the enlargement of antennomeres 5, 7 and 9. The Meru‐noterid clade is the sister group of the remaining Dytiscoidea. The exact position of Aspidytes within this clade remains ambiguous: it is either the sister group of Amphizoidae or the sister group of a clade comprising this family and Hygrobiidae + Dytiscidae. The sister group relationship between Spanglerogyrinae and Gyrininae was strongly supported. The two included genera of Gyrinini form a clade, and Enhydrini are the sister group of a monophylum comprising the remaining Enhydrini and Orectochilini. A branching pattern (Peltodytes + (Brychius + Haliplus)) within Haliplidae was confirmed. Algophilus, Apteraliplus and the Haliplus‐subgenus Liaphlus form a clade. The generic status of the two former taxa is unjustified. The Phreatodytinae are the sister group of Noterinae, and Notomicrus (+ Speonoterus), Hydrocoptus, and Pronoterus branch off successively within this subfamily. The search for the larvae of Meru and a combined analysis of morphological and molecular data should have high priority. © The Willi Hennig Society 2006.  相似文献   

4.
5.
Daohugounectes primitivus, a new genus and species of coptoclavid beetles, is described from 67 fossil larvae from the Jurassic locality of Daohugou, northeastern China. It differs from other coptoclavids in the combination of the following characters: lateral lobes of nasale present; legs relatively short, with tarsi flat and slightly dilated; abdominal tergite VIII almost circular; derivative of abdominal segment IX present; urogomphi short; and helical thickening of tracheae weak. Most of these features are plesiomorphic for the family Coptoclavidae and the superfamily Dytiscoidea. Among dytiscoids, a derivative of abdominal segment IX is present only in the larvae of the recently discovered relic family Aspidytidae.  相似文献   

6.
Abstract:  A partial skull recovered from conglomerates of the Permo-Triassic Buena Vista Formation in Uruguay belongs to a new species, Uruyiella liminea gen. et sp. nov. This species is characterized by a broadly triangular skull with laterally projecting posterior corners, rhytidosteid-like dermal sculpturing, and orbits positioned close to the skull margin. Uruyiella liminea is distinguished from other temnospondyls by a combination of primitive and derived character states, such as the anterior extent of the palatine ramus of the pterygoid, which excludes the ectopterygoid and most of the palatine from the lateral border of the interpterygoid vacuity, and the absence of both tabular horns and otic notches. A phylogenetic analysis places Uruyiella and the enigmatic Early Triassic Laidleria in a clade to which we attach the family name Laidleriidae. The Plagiosauridae and the Laidleriidae form a clade at the base of Dvinosauria, which is the sister group of a clade that includes Stereospondyli and Archegosauroidea. This result is unexpected because Laidleria and Plagiosauridae are nested deeply within Stereospondyli in most phylogenies. The sister-group relationship of Uruyiella and Laidleria suggests that a ghost lineage for the latter genus extends down into the earliest Triassic and perhaps even into the Late Permian, which in turn would suggest survivorship of the Laidleriidae through the Permo-Triassic extinction event.  相似文献   

7.
Nicolas, M. & Rubidge, B.S. 2010: Changes in Permo-Triassic terrestrial tetrapod ecological representation in the Beaufort Group (Karoo Supergroup) of South Africa. Lethaia, Vol. 43, pp. 45–59.
For more than a century, large collections of fossils from the Beaufort Group have been built up at various museums in South Africa and have been handled as separate databases in the individual museums. Because of the unique time-extensive record of continental vertebrate biodiversity represented by the fossils of the Beaufort Group, a single standardized database has been compiled for the fossils collected from the Beaufort Group housed in South African museums. This unique data set has enabled the determination of terrestrial tetrapod ecological representation from the Middle Permian to Middle Triassic Beaufort Group of South Africa. □ Beaufort Group , biodiversity , ecology , Permo-Triassic .  相似文献   

8.
The fossil record of vertebrates in the late Paleozoic and early Mesozoic is investigated in an attemp to evaluate their participation in the Permo-Triassic faunal crisis. On the whole the record of the marine fishes is similar to that of marine invertebrates with a pronounced diversity minimum at the end of the Permian. On the other hand, the fresh-water and euryhaline fishes, together with the amphibians, seem to have experienced minimal diversity somewhat earlier in the Permian and apparently were on the increase at the Permo-Triassic boundary. The major peculiarity in the reptilian record is a great burst of both first appearances and apparent extinctions in the Dzhulfian Stage in Africa; local causes are suspected. Seemingly the Permo-Triassic faunal crisis was mainly a marine event for which a marine cause or causes should be sought.  相似文献   

9.
Abstract. Characters of the head of adephagan larvae were examined and analysed phylogenetically. A labrum which is completely fused to the clypeofrons and the presence of a closed prepharyngeal tube are autapomorphies of Adephaga. Partial reduction of the fossa maxillaris, cardo and stipes forming a functional unit, the immobilization of the lacinia, attachment of M. craniolacinialis to the lateral stipital wall, and loss of one stipitopalpal muscle, are considered autapomorphies of Adephaga excluding Gyrinidae. Complete reduction of the fossa maxillaris and the presence of M. craniostipitalis medialis are possible autapomorphies of Adephaga excluding Gyrinidae and Haliplidae. The presence of caudal tentorial arms, insertion of the galea on the mesal side of palpomere I, and absence of the lacinia are considered synapomorphies of Trachypachidae and Dytiscoidea (Noteridae, Amphizoidae, Hygrobiidae, Dytiscidae). The presence of a slender, elongated process of the head capsule, which articulates with a corresponding socket of the cardo, is a possible autapomorphy of Dytiscoidea. The sinuate frontal sutures, distinctly protruding prementum, shortened M. craniostipitalis medialis, and absence of M. submentopraementalis are considered autapomorphies of Geadephaga excluding Trachypachidae. The presence of a regular row of hairs along the anterior hypopharyngeal margin is a possible autapomorphy of Geadephaga excluding Trachypachidae and Rhysodidae. Improvement of the hypopharyngeal filter apparatus suggests the monophyly of Anisochaeta. Presence of a penicillum and partial reduction of the lacinia are possible autapomorphies of Anisochaeta excluding Omophronini. Larvae of Cychrini, Carabini, Nebriini and Notiophilini are characterized by a strongly developed, cone-shaped hypodon. Postocular and cervical ridges, crosswise arrangement of antennal muscles, and a completely flattened hypopharynx are considered autapomorphies of Caraboidea Limbata.  相似文献   

10.
11.
The superfamily Dytiscoidea contains six families with an aquatic lifestyle, with most of its extant diversity in two families: the burrowing water beetles (Noteridae) and the diving beetles (Dytiscidae). The other families have few species (up to six) and generally highly disjunct extant distributions. Aspidytidae currently contains one genus with two species, one in China and one in South Africa. Here we provide the first molecular data for the Chinese species, allowing us to explore the phylogenetic relationships and position of both species of this small family for the first time. Based on a matrix of 11 genes we inferred a phylogenetic hypothesis for Dytiscoidea including all extant families. Unexpectedly, Aspidytidae were consistently recovered as paraphyletic relative to Amphizoidae, despite being well characterized by apparently synapomorphic adult features. A re‐examination of larval characters in the two aspidytid species revealed that the larva of the Chinese species is strikingly similar to that of Amphizoidae. Both share a series of plesiomorphic features but also some potential synapomorphies, including a dense vestiture of short setae on the head capsule, anteriorly shifted posterior tentorial grooves and widely separated labial palps. Arguably these features may belong to the groundplan of the clade Aspidytidae + Amphizoidae, with far‐reaching secondary modifications (including reversals) in the South African Aspidytes niobe. At present we retain the family Aspidytidae, however, due to the strong adult morphological synapomorphies of the two extant species, and the fact that the molecular paraphyly of the family may result from the highly divergent nature of the two extant species. This long evolutionary separation and strong divergence, in terms of gene sequences and larval features, is undeniable, substantial levels of saturation in third codon positions of protein‐coding genes being present between the two taxa. We address this issue taxonomically by introducing the new genus S inaspidytes gen. nov. for the Chinese Aspidytes wrasei. The continued contentious relationships amongst Dytiscidae, Hygrobiidae, Aspidytidae and Amphizoidae highlight the need for more data to address dytiscoid phylogenetics, possibly involving a genomic approach. © 2016 The Linnean Society of London  相似文献   

12.
田天  袁缓  陈斌 《昆虫学报》1950,63(8):1016-1027
【目的】明确肉食亚目(Adephaga)水生类群线粒体基因组的基本特征,并基于线粒体基因组序列分析肉食亚目水生类群的系统发育关系。【方法】基于Illumina HiSeq X Ten测序技术测定了圆鞘隐盾豉甲Dineutus mellyi和齿缘龙虱Eretes sticticus的线粒体全基因组序列,对其进行了基因注释,并对其tRNA基因二级结构进行了预测分析。加上已公布的鞘翅目(Coleoptera)肉食亚目水生类群17个种的线粒体基因组序列,对该类群共19个种线粒体的蛋白质编码基因(protein-coding genes, PCGs)开展了比较基因组学分析,包括AT含量、密码子偏好性、选择压力等。基于13个PCGs的氨基酸序列和核苷酸序列,利用最大似然法(ML)和贝叶斯法(BI)分别构建鞘翅目肉食亚目水生类群的系统发育关系,并通过FcLM分析进一步评估伪龙虱科(Noteridae)和瀑甲科(Meruidae)的系统发育位置。【结果】圆鞘隐盾豉甲和齿缘龙虱的线粒体基因组全长分别为16 123 bp(GenBank登录号: MN781126)和16 196 bp(GenBank登录号: MN781132),都包含13个PCGs、22个tRNA基因、2个rRNA基因和1个D-loop区(控制区)。19个肉食亚目水生类群线粒体基因组PCGs的碱基组成都呈现A+T偏好性,在密码子使用上也都偏向于使用富含A+T的密码子;在进化过程中13个PCGs的进化模式相同,都受到纯化选择。基于线粒体基因组13个PCGs的氨基酸序列的肉食亚目水生类群的系统发育关系为(豉甲科Gyrinidae+(沼梭甲科Haliplidae+((壁甲科Aspidytidae+(两栖甲科Amphizoidae+龙虱科Dytiscidae))+(水甲科Hygrobiidae+(瀑甲科Meruidae+伪龙虱科Noteridae)))))。【结论】研究结果表明,豉甲科是肉食亚目水生类群的基部类群,接下来是沼梭甲科和龙虱总科;伪龙虱科和瀑甲科互为姐妹群,并一起作为龙虱总科内部的一个分支;两栖甲科与龙虱科具有更近的亲缘关系。  相似文献   

13.
14.
Prokaryotic diversity in Alpine salt sediments was investigated by polymerase chain reaction (PCR) amplification of 16S rRNA genes, sequencing of cloned products, and comparisons with culturable strains. DNA was extracted from the residue following filtration of dissolved Permo-Triassic rock salt. Fifty-four haloarchaeal sequences were obtained, which could be grouped into at least five distinct clusters. Similarity values of three clusters to known 16S rRNA genes were less than 90%-95%, suggesting the presence of uncultured novel taxa; two clusters were 98% and 99% similar to isolates from Permo-Triassic or Miocene salt from England and Poland, and to Halobacterium salinarum, respectively. Some rock salt samples, including drilling cores, yielded no amplifiable DNA and no cells or only a few culturable cells. This result suggested a variable distribution of haloarchaea within different strata, probably consistent with the known geologic heterogeneity of Alpine salt deposits. We recently reported identical culturable Halococcus salifodinae strains in Permo-Triassic salt sediments from England, Germany, and Austria; together with the data presented here, those results suggest one plausible scenario to be an ancient continuous hypersaline ocean (Zechstein sea) populated by haloarchaea, whose descendants are found today in the salt sediments. The novelty of the sequences also suggested avoidance of haloarchaeal contaminants during our isolation of strains, preparation of DNA, and PCR reactions.  相似文献   

15.
Adephaga is the second largest suborder of beetles (Coleoptera) and they serve as important arthropod predators in both aquatic and terrestrial ecosystems. The suborder is divided into Geadephaga comprising terrestrial families and Hydradephaga for aquatic lineages. Despite numerous studies, phylogenetic relationships among the adephagan families and monophyly of the Hydradephaga itself remain in question. Here we conduct a comprehensive phylogenomic analysis of the suborder using ultraconserved elements (UCEs). This study presents the first in vitro test of a newly developed UCE probe set customized for use within Adephaga that includes both probes tailored specifically for the suborder, alongside generalized Coleoptera probes previously found to work in adephagan taxa. We assess the utility of the entire probe set, as well as comparing the tailored and generalized probes alone for reconstructing evolutionary relationships. Our analyses recovered strong support for the paraphyly of Hydradephaga with whirligig beetles (Gyrinidae) placed as sister to all other adephagan families. Geadephaga was strongly supported as monophyletic and placed sister to a clade composed of Haliplidae + Dytiscoidea. Monophyly of Dytiscoidea was strongly supported with relationships among the dytiscoid families resolved and strongly supported. Relationships among the subfamilies of Dytiscidae were strongly supported but largely incongruent with prior phylogenetic estimates for the family. The results of our UCE probe comparison showed that tailored probes alone outperformed generalized probes alone, as well as the full combined probe set (containing both types of probes), under decreased taxon sampling. When taxon sampling was increased, the full combined probe set outperformed both tailored probes and generalized probes alone. This study provides further evidence that UCE probe sets customized for a focal group result in a greater number of recovered loci and substantially improve phylogenomic analysis.  相似文献   

16.
An initial accent on the investigation of megafossils by some well-known Austrian paleobotanists (like Ettinghausen, Stur, Unger) changed with time to a higher degree of research on the histology and anatomy of fossil plants, especially of wood and cuticles by the late E. Hofmann. Due to the large quantity of spores and pollen grains in peat, brown coal, salt rocks, phosphorites, clay and shales in Austria, the major topic of investigation at the present time is clearly devoted to palynology. Quaternary, Neogene and Permo-Triassic microfloras occupy the first place in research. Concerning the determination of pollen and morphologic studies of a selection of modern comparison species by all kinds of light and electron microscopy have been initiated to find out whether biospecific determination could be carried out in the Quaternary and Neogene. An example of pollen-morphological features within the genus Pinus is presented.The microflora of Upper Permian and Triassic sediments of the east Alpine salt rocks, their environment and inclusions receive comprehensive microphotographic documentation and will be backed from a stratigraphic point of view by sulphur-isotope investigations, which promise to be of great value in dating the Permo-Triassic boundary.  相似文献   

17.
The karyotypes of ten species of Holcoglossum (Orchidaceae), a highly endangered and diversified genus from China, were investigated to study the infrageneric relationships, biogeography, and speciation patterns in the Hengduan Mountains. The karyotype formulae of the studied species are as follows: 2 n  = 38 = 20m + 18sm in H. subulifolium , 2 n  = 38 = 22m + 16sm in H. amesianum , 2 n  = 38 = 26m + 12sm (6 SAT) in H. lingulatum , 2 n  = 38 = 26m + 12sm in H. wangii , 2 n  = 38 = 10m + 28sm in H. kimballianum , 2 n  = 38 = 14m + 22sm + 2st in H. flavescens , 2 n  = 38 = 24m + 12sm + 2st in H. rupestre , 2 n  = 38 = 14m + 20sm + 4st in H. sinicum , 2 n  = 38 = 16m + 14sm + 8st in H. weixiense , and 2 n  = 76 in H. tsii . The karyotypes of two tropical species, H. amesianum and H. subulifolium , are the most primitive in the genus, whereas those of four temperate alpine species, H. sinicum , H. rupestre , H. weixiense , and H. flavescens , are more advanced. H. tsii is a tetraploid and H. rupestr e may be one of its ancestors. The low frequency of polyploidy in Holcoglossum in the Hengduan Mountains region supports the conclusion that chromosome stasis during rapid speciation is common there.  © 2007 The Linnean Society of London. Botanical Journal of the Linnean Society , 2007, 154 , 283–288.  相似文献   

18.
Egg, larval, protonymphal and deutonymphal stages of Amblyseius longispinosus (Evans) that fed on Eotetranychus cendanai , required 2.02 ± 0.13, 0.57 ± 0.17, 1.07 ± 0.31 and 1.16 ± 0.53 days, respectively. The total developmental time was 4.79 ± 0.61 days. Female longevity averaged 14.61 ± 2.88 days in which 19.54 ± 6.36 eggs/female or 1.33 ± 0.29 eggs/female per day were laid. The highest predation rate was detected at a prey density of 40–50. Amblyseius longispinosus could be employed as the biological control agent of E. cendanai both in laboratory and greenhouse conditions at the predator : prey ratio of 1 : 30 to 1 : 50.  相似文献   

19.
重新研究了甘肃玉门含大山口动物群的地层,讨论了北祁连区二叠和三叠系划分,指出西大沟组存在误用,建议将上三叠统的西大沟组更名,将中二叠统产大山口动物群的西大沟组更名为青头山组,并将青头山剖面指定为青头山组命名剖面.  相似文献   

20.
Salema Sarpa salpa (Linnaeus, 1758), were caught in the middle-eastern Adriatic Sea from August to November 2004. Length range of the samples was between 10.3 and 43.9 cm, with mean values of 25.5 cm in males, 32.6 cm in females, and 11.4 and 20.2cm in immature and hermaphrodite specimens, respectively. Sex ratio (males : females) was 3.1 : 1. Males were observed up to 37 cm length. Hermaphrodites showed lengths between 18 and 21 cm. The species was characterized by protandric hermaphroditism. Size at sexual maturity was 20.6 cm (2 years old) for males. Total length-total weight relationship for the entire population is described by the parameters a  = 0.00893, and b  = 3.1055. Otolith age readings showed that the population consisted of 15 age groups (1–15 years), including a very high proportion of individuals 1–7 years old. The von Bertalanffy growth parameters were L  = 33.11cm, k  = 0.514, and t 0 = −0.392 years for males and L  = 40.85cm, k  = 0.179, and t 0 = −2.606 years for females. Survival rate of females ( S  = 0.870) was much greater than for males ( S  = 0.769).  相似文献   

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