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1.
A fossil pygmy right whale (Cetacea, Mysticeti, Neobalaenidae) with exquisitely preserved baleen is described for the first time in the history of cetacean palaeontology, providing a wealth of information about the evolutionary history and palaeobiogeography of Neobalaenidae. This exquisitely preserved specimen is assigned to a new genus and species, Miocaperea pulchra gen. et sp. nov. , and differs from Caperea marginata Gray, 1846, the only living taxon currently assigned to Neobalaenidae, in details of the temporal fossa and basicranium. A thorough comparative analysis of the skeleton of M. pulchra gen. et sp. nov. and C. marginata is also provided, and forms the basis of an extensive osteology‐based phylogenetic analysis, confirming the placement of M. pulchra gen. et sp. nov. within Neobalaenidae as well as the monophyly of Neobalaenidae and Balaenidae; the phylogenetic results support the validity of the superfamily Balaenoidea. No relationship with Balaenopteroidea was found by the present study, and thus the balaenopterid‐like morphological features observed in C. marginata must have resulted from parallel evolution. The presence of M. pulchra gen. et sp. nov. around 2000 km north from the northernmost sightings of C. marginata suggests that different ecological conditions were able to support pygmy right whale populations in what is now Peru, and that subsequent environmental change caused a southern shift in the distribution of the living neobalaenid whales. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 876–911.  相似文献   

2.
Zygophyseter varolai , a new genus and species of Physeteroidea (Cetacea, Odontoceti), is based on an almost complete skeleton from the Late Miocene (Tortonian) in southern Italy. The extreme elongation of the zygomatic process of the squamosal and the circular supracranial basin (probably for housing the spermaceti organ) delimited by a peculiar anterior projection of the supraorbital process of the right maxilla are the most distinctive features of this bizarre sperm whale. Large body size, large teeth present in both lower and upper jaw, and anteroposteriorly elongated temporal fossa and zygomatic process of the squamosal indicate that this cetacean (for which we suggest the English common name killer sperm whale) was an active predator adapted to feeding on large prey, similarly to the extant killer whale ( Orcinus orca ). A phylogenetic analysis reveals that Zygophyseter belongs to a Middle–Late Miocene clade of basal physeteroids, together with Naganocetus (new genus for the type of ' Scaldicetus ' shigensis ). Moreover, the phylogenetic analysis shows evidence of a wide physeteroid radiation during the Miocene and that the extant Physeter and Kogia belong to two distinct families that form a clade representing the crown-group Physeteroidea.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 103–131.  相似文献   

3.
Abstract:  A new basal balaenopterid genus and species, Archaebalaenoptera castriarquati , is described and compared with all the living and fossil members of the family Balaenopteridae and related fossil rorqual-like taxa. It was found in the Lower Pliocene of northern Italy, and is characterized by a supraoccipital with a transversely compressed anterior process, the zygomatic process of the squamosal diverging from the longitudinal axis of the skull, very long nasal bones, and subtle exposition of the parietal on the dorsal wall of the skull. It is primitive in having a maxilla with a long ascending process that is posteriorly unexpanded and round, and a dentary that is straight and not bowed outward, unlike that of living Balaenopteridae. In particular, the discovery of this new genus suggests that, among the early members of Balaenopteridae, the acquisition of the typical sutural pattern shown by maxilla, frontal, parietal and supraoccipital preceded the acquisition of the feeding-related traits that are characteristic of the family. The primitive morphology of the feeding-related structures of A. castriarquati (i.e. the straight dentary and the flat glenoid fossa of the squamosal) suggests that this whale was unable to undertake the intermittent ram feeding typical of Balaenopteridae as efficiently as living members of the family.  相似文献   

4.
记述了四川省自贡市汇东新区自贡市乳品厂发现的西蜀鳄一新种——周氏西蜀鳄(Hsisosuchus chowi sp.nov.)。新种区别于西蜀鳄已知种的特征是:鼻骨后部沿缝合线有一浅的纵凹,额骨的眶缘向上凸起成嵴,沿额骨缝合线也隆起成一微弱的纵嵴,上颞窝的内侧缘向上凸起呈明显的嵴,顶骨具一前中突,侧视颧骨腹缘呈明显的波曲状,眶后骨前侧角约90°,鳞骨后侧突特别拉长,向侧下后方伸展,使鳞骨侧缘明显向内侧弓曲,左右外枕骨的枕髁部分不相接,翼骨的腹中嵴源于翼骨主体部分,内鼻孔位置比较靠前。此外,齿骨外面和夹板骨腹面具有发达的沟和嵴状雕饰,夹板骨参与下颌联合的部分比较长,肩胛片异常扩展,乌喙骨远端宽于近端,肱骨头增厚并强烈向内侧扩展,三角肌嵴发达,桡侧腕骨具发达的尺骨突,尺侧腕骨远端宽于近端,6列荐前部腹部骨板和3列尾部腹部骨板,也可能是周氏西蜀鳄的衍生特征,但这些性状在大山铺西蜀鳄中情况不明,有待更多的材料来证实。杨钟健、周明镇(1953)在建立西蜀鳄属之初就已注意到西蜀鳄是一种特化的鳄类,认为西蜀鳄不仅将原始特征和进步特征混存于一身,而且还具有一些一般鳄类所没有的独特性质。以此为基础,他们建立了西蜀鳄科。目前西蜀鳄类动物发现并不多,仅有1属2种,即重庆西蜀鳄和大山铺西蜀鳄,而且材料不完整,特别是头后骨骼保存不理想。周氏西蜀鳄的发现不仅扩大了西蜀鳄类的分布范围,而且还增加了我们对这一特化鳄类的认识。  相似文献   

5.
Rorqual whales (Family: Balaenopteridae) are the world's largest predators and sometimes feed near or at the sea surface on small schooling prey. Most rorquals capture prey using a behavioral process known as lunge‐feeding that, when occurring at the surface, often exposes the mouth and head above the water. New technology has recently improved historical misconceptions about the natural variation in rorqual lunge‐feeding behavior yet missing from the literature is a dedicated study of the identification, use, and evolution of these behaviors when used to capture prey at the surface. Here we present results from a long‐term investigation of three rorqual whale species (minke whale, Balaenoptera acutorostrata; fin whale, B. physalus; and blue whale, B. musculus) that helped us develop a standardized classification system of surface lunge‐feeding (SLF) behaviors. We then tested for differences in frequency of these behaviors among the three species and across all rorqual species. Our results: (1) propose a unified classification system of six homologous SLF behaviors used by all living rorqual whale species; (2) demonstrate statistically significant differences in the frequency of each behavior by minke, fin, and blue whales; and (3) provide new information regarding the evolution of lunge‐feeding behaviors among rorqual whales.  相似文献   

6.
A new hadrosaurid dinosaur, Arenysaurus ardevoli gen. et sp. nov., from the Late Maastrichtian of Aren (Huesca, South-central Pyrenees) is described on the basis of a partial, articulated skull, mandibular remains and postcranial elements, including vertebrae, girdle and limb bones. Arenysaurus is characterized by having a very prominent frontal dome; nearly vertical prequadratic (squamosal) and jugal (postorbital) processes, and deltopectoral crest of the humerus oriented anteriorly. Moreover, it possesses a unique combination of characters: short frontal (length/width approximately 0.5); midline ridge of parietal at level of the postorbital-squamosal bar; parietal excluded from the occiput; squamosal low above the cotyloid cavity. A phylogenetical analysis indicates that Arenysaurus is a rather basal member of Lambeosaurinae and the sister-taxon to Amurosaurus and the Corythosaurini-Parasaurolophini clade. The phylogenetic and biogeographical relationships of Arenysaurus and other lambeosaurines suggest a palaeogeographical connection between Asia and Europe during the Late Cretaceous.  相似文献   

7.
Abstract: A rich, diverse Permian ostracod fauna has been recovered from the red and grey, laminated shales and quartz‐rich shales of the Triassic Lercara Formation. Forty‐seven species have been identified, 13 of which are newly described here; they belong to 26 genera of which three are new: Anahuacia lercaraensis sp. nov., Aurigerites siciliaensis sp. nov., Bairdia portellaensis sp. nov., Cristanaria? katyae sp. nov., Fabalicypris gruendeli sp. nov., Lethiersa salomonensis gen. et sp. nov., Lethiersia sinusoventralis gen. et sp. nov., Portella trapezoida gen. et sp. nov., Siciliella elongata gen. et sp. nov., Siciliella infernespinosa gen. et sp. nov., Siciliella prima gen. et sp. nov., Siciliella quadrata gen. et sp. nov., and Siciliella spinorobusta gen. et sp. nov. The assemblages contain or are composed of palaeopsychrospheric forms, which are regarded as index fossils for deep environments. The bathymetry of the different associations in life is evaluated.  相似文献   

8.
We describe the morphology and biology of a previously unknown form of branching annelid, Ramisyllis multicaudata gen. et sp. nov. , an endosymbiont of shallow‐water marine sponges (Petrosia sp., Demospongiae) in northern Australia. It belongs to the polychaete family Syllidae, as does Syllis ramosa McIntosh, 1879, the only other named branching annelid, which was collected from deep‐water hexactinellid sponges during the 1875 Challenger expedition. It differs from S. ramosa in parapodial and chaetal morphology. Ramisyllis multicaudata gen. et sp. nov. has segments of several types, including specialized posterior segments on the emergent portions of the worm, and simplified elongate segments that bridge larger cavities in the sponge interior. Aside from the obvious branching form, the new annelid is similar to Parahaplosyllis, differing from it in lacking pharyngeal armature and in the details of the parapodial chaetae and dorsal cirri. Molecular evidence from 16S and 18S rDNA supports a sister‐group relationship with Parahaplosyllis, with both being sister to Trypanosyllis and Eurysyllis. The phylogenetic position of R. multicaudata gen. et sp. nov. indicates that branching has evolved independently in Ramisyllis gen. nov. and Syllis. This is supported by differences in the branching process between the two taxa: in S. ramosa branching is initiated by segment addition at the parapodium, whereas in R. multicaudata gen. et sp. nov. segments are added from a region between parapodia. A model for branching in R. multicaudata gen. et sp. nov. is proposed and possible developmental processes underlying branching in Annelida, and body symmetry comparisons with other invertebrates, are also discussed. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 481–497.  相似文献   

9.
Abstract:  A new pliosaurid, Gallardosaurus iturraldei gen nov. et sp. nov., was found in the Viñales area, western Cuba, in sediments of the Jagua Formation, middle–late Oxfordian. This new taxon is characterized by: wide participation of the premaxilla in the outer margin of the external naris; frontal not participating in the orbital margin; postorbital in contact with the jugal and squamosal; presence of anterior pterygoid vacuity; cultriform process of parasphenoid convex and exposed in palatal view; pterygoid flanges high; jaw articulation low relative to tooth row; trihedral teeth in cross-section and with smooth ridges at least in the labial face. A phylogenetic analysis suggests that Gallardosaurus forms a clade with Peloneustes , the most common pliosaurid genus occurring in the Oxford Clay. The Caribbean Seaway was, at least since the Oxfordian, a corridor that permitted the interchange for marine biota between Western Tethys and Eastern Pacific realms. Among vertebrates, bony fish and long-necked plesiosaurs prevailed. However, marine pleurodiran turtles, metriorhynchid crocodilians, ophthalmosaurian ichthyosaurs, and pliosaurids ( G. iturraldei gen. nov. et sp. nov.) have also been found, as well as at least two species of pterosaurs, and one camarasaurian dinosaur. Among these reptiles there were off-shore pelagic forms such as the ichthyosaurs and metriorhynchids, together with the pliosaurid G. iturraldei gen. nov. et sp. nov.; other taxa were presumably less pelagic, such as the pleurodiran turtles and the cryptoclidid plesiosauroids. Gallardosaurus iturraldei gen. nov. et sp. nov. would have played the role of an active predator taking advantage of nectonic fish recorded in the area.  相似文献   

10.
The Hippasterinae is a subfamily within the Goniasteridae, consisting of five genera and 26 species, which occur in cold‐water settings ranging from subtidal to abyssal depths. All known genera were included in a cladistic analysis resulting in two most parsimonious trees, supporting the Hippasterinae as monophyletic. Our review supports Sthenaster emmae gen. et sp. nov. as a new genus and species from the tropical Atlantic and two new Evoplosoma species, Evoplosoma claguei sp. nov. and Evoplosoma voratus sp. nov. from seamounts in the North Pacific. Hippasteria caribaea is reassigned to the genus Gilbertaster, which previously contained a single Pacific species. Our analysis supports Evoplosoma as a derived deep water lineage relative to its continental‐shelf, shallow water sister taxa. The genus Hippasteria contains approximately 15 widely distributed, but similar‐looking species, which occur in the northern and southern hemispheres. Except for Gilbertaster, at least one species in each genus has been observed or is inferred to prey on deep‐sea corals, suggesting that this lineage is important to the conservation of deep‐sea coral habitats. The Hippasterinae shares several morphological similarities with Circeaster and Calliaster, suggesting that they may be related. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 266–301.  相似文献   

11.
Abstract: Four new Brachycera fossils were collected from the Daohugou biota, China. Among these, two impressions demonstrating peculiar wing venation can be designated as two new species of a new genus (Mostovskisargus portentosus gen. et sp. nov. and M. signatus sp. nov.) referred to a new subfamily Mostovskisarginae (subfam. nov.) within Archisargidae. The third impression belongs to a new species (Calosargus (Pterosargus) sinicus sp. nov.) referred to the subgenus Pterosargus Mostovski, 1997 of Calosargus Mostovski, 1997 within Archisarginae, Archisargidae. It is only the second member of the subgenus Pterosargus worldwide. The fourth impression is a nearly complete fly, Jurassinemestrinus orientalis gen. et sp. nov. referable to Rhagionemestriidae. It reveals new morphological data about rhagionemestriids and extends the geographical distribution of this group beyond Europe and Central Asia during the Mesozoic. A correlation for the archisargid composition of taxa in Daohugou and Karabastau formations is discussed. The age of the fly‐bearing strata is briefly reassessed and can be more accurately limited to the Callovian–Oxfordian based on both biostratigraphical correlation and radiometric dating.  相似文献   

12.
A new metriorhynchid crocodylomorph from the Lower Kimmeridge Clay Formation (Kimmeridgian, Upper Jurassic) of England is described. This specimen, a three‐dimensionally preserved skull and left mandibular ramus, is referred to a new species: T orvoneustes coryphaeus sp. nov. Within the genus Torvoneustes, T . coryphaeus sp. nov. is unique as it has a long anteromedial process of the frontal, ornamented dermatocranium, and the supraorbital notch forms a strongly acute angle. Our phylogenetic analysis confirms the placement of this specimen in Torvoneustes. The dentition of T . coryphaeus sp. nov. , like that of the type species, has a blunt apex, crown basal–mid regions with numerous tightly packed apicobasally aligned ridges, and apical region with an anastomosed pattern of ridges that interact with the carinae. Within Thalattosuchia these dental characteristics are only found in Torvoneustes and the teleosaurid Machimosaurus. The heavily ornamented dermatocranium of T . coryphaeus sp. nov. is in contrast to the unornamented (nasals and frontal)–lightly ornamented (maxillae and premaxillae) pattern seen in Torvoneustes carpenteri. Curiously, this pattern of reduction and loss of dermatocranium ornamentation is also observed in Metriorhynchus, Dakosaurus, and the subclade Rhacheosaurini. We hypothesize that the ‘smooth’ dermatocranium of Late Jurassic metriorhynchids evolved independently in each subclade (parallel evolution), and would have reduced drag, thereby making locomotion through water more energy efficient. © 2013 The Linnean Society of London  相似文献   

13.
A new family of Laniatores, Gerdesiidae fam. nov., is proposed based on molecular and morphological evidence. Data also indicate that this new family is the sister family of Tricommatidae. Gerdesiidae fam. nov. has a disjunct distribution, occurring in northern South America (Peru, Brazilian Amazon) and at a spot in south‐eastern Brazil (Minas Gerais State). The new family is composed of two genera: Gerdesius Roewer, 1952 (type genus) and G onycranaus gen. nov. (type species G onycranaus androgynus sp. nov. ). We propose the synonymy of Huralvioides H. Soares, 1970 with Gerdesius Roewer, 1952 based on molecular and morphological evidence. Three new species are described: G erdesius mapinguari sp. nov. (type locality: Brazil, Amazonas, Manaus, Reserva Km 41); G onycranaus androgynus sp. nov. (type locality: Brazil, Minas Gerais, Conceição do Mato Dentro); and an obligate cave‐dwelling species, G onycranaus pluto sp. nov. (type locality: Brazil, Minas Gerais, Morro do Pilar). © 2015 The Linnean Society of London  相似文献   

14.
The insects known as thrips are commonly thought of as flower‐living and pestiferous organisms, but we report here a novel interaction between a phlaeothripine thrips species, Mirothrips arbiter gen. et sp. nov. and three species of social paper wasps in Brazil. This thrips species breeds inside the wasp colonies, and larval and adult thrips feed on wasp eggs, which become severely damaged. Infested nests can contain up to 300 M. arbiter gen. et sp. nov. individuals. The closest relatives of M. arbiter are two presumably predaceous species: Mirothrips bicolor sp. nov. , which inhabits abandoned Cecidomyiidae galls, and Mirothrips analis comb. nov. , described from individuals collected in the silken bags of the caterpillars of Psychidae moths. The behaviour exhibited by M. arbiter represents one of the most evolutionarily advanced lifestyles known among Thysanoptera, and we predict that other polistine species serve as hosts for this thrips in Brazil. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 332–341.  相似文献   

15.
16.
Abstract: Chondrichthyans are newly reported from the autochthonous Wordian Khuff Formation (middle Permian), cropping out in well‐exposed, low‐palaeolatitude sections in the interior Haushi‐Huqf area of Oman. The shark remains comprise isolated teeth, dermal denticles and fin spines and have been recovered by processing limestone in buffered acetic acid from bulk rock samples. The fauna consists of mainly ctenacanthiform and hybodontiform taxa, identified as Glikmanius cf. myachkovensis, Glikmanius culmenis sp. nov., Omanoselache hendersoni gen. et sp. nov., Omanoselache angiolinii gen. et sp. nov., cf. Omanoselache sp., Reesodus underwoodi gen et sp. nov., Teresodus amplexus gen. et sp. nov., Gunnellodus bellistriatus, Khuffia lenis gen. et sp. nov., Khuffia prolixa gen. et sp. nov. and Euselachii sp. indet. Additional specimens include rare teeth of the lonchidiid cf. ‘Palaeozoic Genus 1’ sp., of the neoselachian Cooleyella cf. fordi and a further indeterminate neoselachian, of an indeterminate petalodont and of the holocephalan Deltodus aff. mercurei and Solenodus cf. crenulatus. Fin spines add a further two taxa, Nemacanthus sp. and Amelacanthus cf. sulcatus, which have neoselachian affinities and therefore an unclear relationship to the recovered teeth. The occurrence of Nemacanthus within this Wordian fauna represents the oldest record of this taxon and its only known occurrence in the Palaeozoic. Of the remaining genera, Glikmanius has previously been recorded from the Wordian, whereas for all the others, this study represents their youngest known stratigraphic occurrence and first occurrence in Guadalupian (middle Permian) strata. This adds significantly to our knowledge of the global diversity of chondrichthyans preceding the end‐Guadalupian biotic crisis. Palaeogeographically, for all taxa, this study represents the first record from the western fringe of the marine Neotethyan basin, and only Cooleyella was previously known from the southern (Gondwanan) part of the Pangaean continental margin.  相似文献   

17.
A new subfamily of predaceous diving beetles, Liadytiscinae subfam. nov., including two genera and four species, Liadytiscus gen. nov. (L. cretaceus sp. nov., L. longitibialis sp. nov., and L. latus sp. nov.) and Liadroporus gen. nov. (L. elegans sp. nov.), from the Late Tithonian-Berriasian (Huangbanjigou, Yixian Formation) of China is described. Two new genera, Mesoderus gen. nov. with two species, M. magnus sp. nov. and M. ventralis sp. nov., and Sinoporus gen. nov. with one species, S. lineatus sp. nov., are also described; their position in the system of Dytiscidae remains uncertain. Relationships of the taxa described with Recent and fossil taxa of the same rank and some presumable ecological features of the new taxa are discussed.  相似文献   

18.
Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.  相似文献   

19.
Members of Calamyzinae, a clade of free‐living and ectoparasitic chrysopetalids, are mainly associated with deep‐sea chemosynthetic environments. The three currently known free‐living calamyzin species are placed in Vigtorniella. A new free‐living calamyzin species similar to these is described here. Phylogenetic analyses of Calamyzinae using mitochondrial (cytochrome c oxidase subunit I and 16S rDNA) and nuclear (Histone H3 and 18S rDNA) loci showed that Vigtorniella and the new species form a grade with respect to an ectoparasitic clade, requiring two new genera to be erected. All free‐living calamyzins show a similar anterior end and chaetal morphology. Micospina auribohnorum gen. et sp. nov. is described for the small‐bodied new species from deep‐sea whale falls off California and methane seeps off Costa Rica. The maximum‐likelihood and Bayesian analyses show Micospina gen. nov. as sister to the ectoparasitic clade. Boudemos gen. nov. is named for the clade of two larger‐bodied species: Boudemos flokati gen. et comb. nov. and Boudemos ardabilia gen. et comb. nov., which is sister group to all other Calamyzinae. Vigtorniella is retained for the type species, Vigtorniella zaikai (Kiseleva, 1992), with the adults found amongst bacterial mats at the boundary of the hydrogen sulphide zone in the Black Sea. Micospina gen. nov., Boudemos gen. nov., and Vigtorniella form a grade of free‐living taxa that is associated with feeding on organic‐enriched sediments, and the latter two taxa display ontogenetic jaw change. Jaws are absent in Micospina auribohnorum gen. et sp. nov. and most of the calamyzin clade of parasitic forms.  相似文献   

20.
The Anjihaihe Formation in the southern edge of the Junggar Basin was previously considered a series of freshwater lacustrine depositions. However, abundant marine dinoflagellate cysts were recently recovered from the middle to upper part of the middle member of the formation. Two new genera, six new species and one new subspecies among the abundant dinoflagellate cysts are described and illustrated, i.e. Circulodinium? laeve sp. nov., Kaiwaradinium abbreviatum sp. nov., Spiniferites adnatus subsp. latispinus subsp. nov., Oligosphaeropsis accreta gen. et. sp. nov., Oligosphaeropsis complex gen. et. sp. nov., Oligosphaeropsis megaprocessa gen. et. sp. nov. and Tianshandinium biconicum gen. et. sp. nov. They are rare to common constituents of the dinoflagellate assemblage in the Anjihaihe Formation and may prove useful for regional biostratigraphic correlation and palaeoenvironment re-establishment.  相似文献   

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