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A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus  +  Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472.  相似文献   

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The Xenarthra, particularly the Tardigrada, are with the Notoungulata and Marsupialia among the most diversified South American mammals. Lujanian South American Land Mammal Age localities from the coastal Piedra Escrita site and Andean Casa del Diablo Cave, Peru, have yielded three specimens of the Megalonychidae Diabolotherium nordenskioldi gen. nov. This singular fossil sloth exhibits a peculiar mosaic of cranial and postcranial characters. Some are considered convergent with those of other sloths (e.g. 5/4 quadrangular teeth, characteristic of Megatheriidae), whereas others clearly indicate climbing capabilities distinct from the suspensory mode of extant sloths. The arboreal mode of life of D. nordenskioldi is suggested by considerable mobility of the elbow, hip, and ankle joints, a posteriorly convex ulna with an olecranon shorter than in fossorial taxa, a radial notch that faces more anteriorly than in other fossil sloths and forms an obtuse angle with the coronoid process (which increases the range of pronation–supination), a proximodistally compressed scaphoid, and a wide range of digital flexion. D. nordenskioldi underscores the great adaptability of Tardigrada: an arboreally adapted form is now added to the already known terrestrial, subarboreal, and aquatic (marine and freshwater) fossil sloths. A preliminary phylogenetic analysis of the Tardigrada confirmed the monophyly of Megatherioidea, Nothrotheriidae, Megatheriidae, and Megalonychidae, in which Diabolotherium is strongly nested.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 179–235.  相似文献   

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Nemerteans of the Great Barrier Reef 3. Anopla Heteronemertea (Lineidae)   总被引:3,自引:0,他引:3  
Nine species of lineid heteronemerteans are recorded from the Great Barrier Reef province of Australia. Six of these are new species, including four new genera, and are fully described and illustrated. These are Aetheorhynchus actites gen. et sp. nov. , Bennettiainsularis gen. et sp. nov., Cerebratulus magnetkus sp. nov., Colemania albulus gen. et sp. nov., Mkrura tridacnae sp. nov. and Quasilineus pulcherrimus gen. ct sp. nov. Lineus tricuspidatus (Quoy & Gaimard) is re-established, illustrated and described. Gorgonorhynchus repens Dakin & Fordham and Parborlasia hutchingsi Gibson have been fully described elsewhere, but a full list of known locations is provided.  相似文献   

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Two new genera and species of reptantic polystiliferous hoplonemerteans from the Great Barrier Reef province of Australia are described and illustrated. Urichonemertes pilorhynchus gen. et sp. nov. and Xenonemertes rhamphocephalus gen. et sp. nov. are both placed in the family Drepanophoridae (Polystilifera: Eureptantia: Aequifurcata).  相似文献   

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云南省蚱科一新属新种(直翅目:蚱科)   总被引:4,自引:0,他引:4  
本文报道蚱科一新属一新种。新属,微翅蚱属Alulatettix gen nov.的主要特征是前胸背板强烈隆起呈屋脊形,前胸背板侧片后缘具二凹陷,前、后翅甚微小。其模式种为云南微翅蚱Alulatettix yunnanensis sp.nov.  相似文献   

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记述龙蝎蛉新科Drakonochoristidae fam. nov.和1新亚科及其2新属、种和1个老亚科。2新属种的化石标本采自中国陕西铜川中三叠统铜川组下段上部的灰绿色泥岩和页岩。新科性质及其分类位置在文中进行讨论。新科的建立填补这个类群在中国的空白,同时对于小蝎蛉科Nannochoristidae和二叠蝎蛉科Permochoristidae的演化关系的研究有一定的意义。这些新属、种系陕西昆虫群(陕西生物群的一个类别)铜川昆虫组合的新成员。铜川组的时代相当于欧洲拉丁尼期(Ladinian Stage)。  相似文献   

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Five Ceramiaceae (Rhodophyta) are reported from the offshore waters of the southeastern, warm temperate coast of the United States. These include two new monotypic genera, Calliclavula trifurcate Schneider in the Griffithsieae and Nwynea grandispora Searles in the Sphondylothamnieae, and three new species, Callithamniella silvae Searles, Ptilothamnion occidentale Searles, and Lejolisia exposita Schneider et Searles.  相似文献   

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A new ceramiaceous alga, Sciurothamnion stegengae De Clerck et Kraft, gen. et sp. nov., is described from the western Indian Ocean and the Philippines. Sciurothamnion appears related to the tribe Callithamnieae on the basis of the position and composition of its procarps and by the majority of post‐fertilization events. It differs, however, from all current members of the tribe by the presence of two periaxial cells bearing determinate laterals per axial cell. Additionally, unlike any present representative of the subfamily Callithamnioideae, no intercalary foot cell is formed after diploidization of the paired auxiliary cells. The genus is characterized by a terminal foot cell (“disposal cell”), which segregates the haploid nuclei of the diploidized auxiliary cell from the diploid zygote nucleus. The nature of three types of foot cells reported in the Ceramiaceae (intercalary foot cells containing only haploid nuclei, intercalary foot cells containing haploid nuclei and a diploid nucleus, and terminal foot cells containing only haploid nuclei) is discussed.  相似文献   

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Sphaerodactyl geckos comprise five genera distributed across Central and South America and the Caribbean. We estimated phylogenetic relationships among sphaerodactyl genera using both separate and combined analyses of seven nuclear genes. Relationships among genera were incongruent at different loci and phylogenies were characterized by short, in some cases zero length, internal branches and poor phylogenetic support at most nodes. We recovered a polyphyletic Coleodactylus, with Coleodactylus amazonicus being deeply divergent from the remaining Coleodactylus species sampled. The C. amazonicus lineage possessed unique codon deletions in the genes PTPN12 and RBMX while the remaining Coleodactylus species had unique codon deletions in RAG1. Topology tests could not reject a monophyletic Coleodactylus, but we show that short internal branch lengths decreased the accuracy of topology tests because there were not enough data along short branches to support one phylogenetic hypothesis over another. Morphological data corroborated results of the molecular phylogeny, with Coleodactylus exhibiting substantial morphological heterogeneity. We identified a suite of unique craniofacial features that differentiate C. amazonicus not only from other Coleodactylus species, but also from all other geckos. We describe this novel sphaerodactyl lineage as a new genus, Chatogekko gen. nov. We present a detailed osteology of Chatogekko, characterizing osteological correlates of miniaturization that provide a framework for future studies in sphaerodactyl systematics and biology.  相似文献   

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云南省厉螨科一新属新种(蜱螨亚纲:革螨股)   总被引:4,自引:0,他引:4  
在云南陇川县的蟋蟀Gryllus sp.体上采得一种革螨,系厉螨科Ltelapidae Berlese中未曾描述过的种类,并为之建立新属,订名为滇厉螨属Dianolaelaps gen.nov.,属模标本为蟋蟀滇厉螨Dianolaelaps gryllus sp.nov.。新属的主要鉴别特征是:雌螨螯钳动趾端部分三叉;颚角内侧有沟漕并具齿突;口下片末端,在颚角与下咽间有长圆形结构,其内缘并具透明的尖齿列;涎针有膜状结构包绕;足Ⅰ—Ⅲ基节各具一棘,各基节远端侧具细小毛列。  相似文献   

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The only member of the red algal family Solieriaceae known from New Zealand is the endemic Sarcodiotheca colensoi (Hook. & Harv.) Kylin. This study shows that it differs in several respects from the type S. furcata (Setch. & Gard.) Kylin; thus a new genus Placentophora is created for the New Zealand alga. Although P. colensoi nov. comb. is retained in the Solieriaceae on the basis of vegetative, spermatangial, tetrasporangial, carpogonial-branch and early gonimoblast features, it differs from typical members of that family in its pattern of later carposporophyte development. After a single gonimoblast initial is cut off from the auxiliary cell towards the center of the thallus, further gonimoblasts develop from the initial as ramifying, radiating filaments. These filaments enter an extensive “nutritive-cell” region surrounding the auxiliary cell, form, numerous connections to the “nutritive” cells, and incorporate most of them into a central placenta of interconnected, and variously-fused vegetative and gonimoblast cells. Carpo-sporangia then form in short chains around the periphery of the placenta. The cystocarp lacks both a central fusion cell and a sterile-celled investment, or “Faserhülle.” The distinctive carposporophyte of Placentophora is compared to patterns of gonimoblast development, known in other members of the Solieriaceae.  相似文献   

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A new genus, Augophyllum Lin, Fredericq et Hommersand gen. nov. related to Nitophyllum, tribe Nitophylleae, subfam. Nitophylloideae of the Delesseriaceae, is established to contain the type species Augophyllum wysorii Lin, Fredericq et Hommersand sp. nov. from Caribbean Panama; Augophyllum kentingii Lin, Fredericq et Hommersand sp. nov. from Taiwan; Augophyllum marginifructum (R. E. Norris et Wynne) Lin, Fredericq et Hommersand comb. nov. (Myriogramme marginifructa R. E. Norris et Wynne 1987) from South Africa, Tanzania, and the Sultanate of Oman; and Augophyllum delicatum (Millar) Lin, Fredericq et Hommersand comb. nov. (Nitophyllum delicatum Millar 1990 ) from southeastern Australia. Like Nitophyllum, Augophyllum is characterized by a diffuse meristematic region, the absence of macro‐ and microscopic veins, procarps consisting of a supporting cell bearing a slightly curved four‐celled carpogonial branch flanked laterally by a cover cell and a sterile cell, a branched multicellular sterile group after fertilization, absence of cell fusions between gonimoblast cells, and tetrasporangia transformed from multinucleate surface cells. Augophyllum differs from Nitophyllum by the blades becoming polystromatic inside the margins, often with a stipitate cylindrical base, the possession of aggregated discoid plastids neither linked by fine strands nor forming bead‐like branched chains, spermatangia and procarps initiated at the margins of blades, not diffuse, and a cystocarp composed of densely branched gonimoblast filaments borne on a conspicuous persistent auxiliary cell with an enlarged nucleus. Analyses of the rbcL gene support the separation of Augophyllum from Nitophyllum. An investigation of species attributed to Nitophyllum around the world is expected to reveal other taxa referable to Augophyllum.  相似文献   

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在贵阳市土马陆Julus terrestris 体上采得一种革螨,系未曾描述过的新种,并为其建立新科、新属,以其背板周围具细毛这一特征而命名为:毛盾螨科Trichoaspididae和毛盾螨属Trichoaspis。模式种:马陆毛盾螨,新种Trichoaspis julus sp.nov.  相似文献   

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叶刺瘿螨亚科一新属三新种:真螨目:瘿螨科   总被引:1,自引:0,他引:1  
新属为新诺尔瘿螨属Neoknorella Kuang et Feng,gen.nov.三新种是竹新诺尔瘿螨Neoknorella bambusae sp.nov.,竹裂柄瘿螨 Dichopelmus bambusae sp.nov.和樟无伪足瘿Anothopoda cinnamomi sp.nov.,它们均营自由生活。  相似文献   

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革螨一新属新种及一新科的建立(蜱螨亚纲:革螨股)   总被引:3,自引:0,他引:3  
在云南陇川县的蜣螂体上采得一种革螨系未曾描述过的新种,并为之建立新科与新属,用其颚角呈球形膨大及躯体角化较深的特征命名。球革螨科新科Bulbogamasidae fam.nov.的主要特征:叉毛三叉,其侧具一拇指状薄膜;颚角呈球形膨大,角化弱;头盖前缘光滑;雄螨足11具强大的距状表皮突。球革螨属新属Bulbogamasus gen.nov.的主要特征:背板整块;背毛26对,板周围的长大,中部的细小;胸叉叉丝末端具刺状突,小分支端部有的分叉;雌螨具腹肛板与肛前毛;雄螨导精趾粗长,超过螯钳长的2倍以上。模式种为中华球革螨新种Bulbogamasus sinicus sp.nov.  相似文献   

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