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1.
An intensive study of a collection of arthropods from the Cretaceous of Lebanon, formerly referred to as stomatopod larvae, reveals that these forms belong to the problematical arthropod class Thylacocephala. The species Protozoea hilgendorfi , P. damesi , and Pseuderichthus cretaceus display defining thylacocephalan characters such as a carapace enclosing the entire body bearing a large anterior optic notch; three pairs of large, raptorial appendages; and a posterior battery of small swimming limbs associated with muscle segments. Unique characters of at least the genus Protozoea are the numerous 'pits' covering the entire carapace, elongated anterior rostral and posterior spines, and a dorsal hinge indicative of a truly bivalved carapace. We note several anatomical curiosities that provide some insight into the anatomy, ecology and phylogenetic relationships of these and other thylacocephalan species. Structures on the carapace surface of thylacocephalans may represent sensory organs comparable to the receptors seen on thecostracan crustaceans. The affinities of the three species described are still not entirely clear, but a phylogenetic analysis of the entire group may resolve this.  相似文献   

2.
Until now, only two Psychodoidea were known from Lebanese amber. We describe two new genera and species of Phlebotomidae ( Mesophlebotomites hennigi gen. et sp. nov., Libanophlebotomus lutfallahi gen. et sp. nov.) and four new genera with six new species of Psychodidae ( Paleopsychoda solignaci gen. et sp. nov., Paleopsychoda jacquelinae sp. nov., Protopsychoda nadiae gen. et sp. nov., Protopsychoda hammanaensis sp. nov., Libanopsychoda abillamai gen. et sp. nov., Cretapsychoda inexpectata gen. et sp. nov.) from the Lower Cretaceous amber of Hammana/Mdeirij, Lebanon. These fossils are included in a phylogenetic analysis of the subfamilies of Psychodoidea. This superfamily was probably as diverse in the Early Cretaceous as now.  相似文献   

3.
Ankylosaurian remains from the Transylvanian Basin, Romania, are extremely rare. More than 100 years after the discovery of the first and only better-known assemblage, namely the type material of Struthiosaurus transylvanicus, new ankylosaurian material has been discovered in the Maastrichtian of the Ha?eg Basin, as well as at another locality (Vurp?r), in the Transylvanian Basin, that is described here. The material consists of one tooth in a small jaw fragment (from the Ha?eg Basin) and at least two accummulations of associated, as well as several isolated, postcranial elements (from Vurp?r). No diagnostic elements are preserved that would overlap with the type of Stransylvanicus, so we cannot assign any of the new specimens to this species. The tooth shows marked differences compared to those of other anklyosaurs including S. austriacus and Hungarosaurus in having only six, more or less equally sized, apically pointed cusps separated by deep grooves. The postcranial material from Vurp?r represents at least three different individuals. The humerus is the most diagnostic element among the postcranial remains being most similar both in size and morphology to humeri referred to as Struthiosaurus from different European localities, thus here we refer the humerus and probably associated elements preserved in one assemblage to as cf. Struthiosaurus sp.; the remaining specimens from Vurp?r are retained as Nodosauridae indet. Histological studies have confirmed the adult nature of all sampled bones in the Vurp?r ankylosaur material suggesting that these fully grown animals were of similar size to Struthiosaurus, a small-bodied nodosaurid the ontogenetic status of which, however, has never been investigated histologically. The obviously diminished body size of the Transylvanian ankylosaurs compared to other members of the clade could be explained by insular dwarfism using the same histology-based argument as presented for Magyarosaurus.  相似文献   

4.
Thairia transbaikalica Felker et Vasilenko, gen. et sp. nov. (Odonata, Hemiphlebiidae) from the Mesozoic Chernovskie Kopi locality is described. A short review of known genera of Hemiphlebiidae is provided. Relative age of enclosing rocks is discussed.  相似文献   

5.
Two taxa of cupulate magnoliid fossil flowers, Cronquistiflora and Detrusandra, are described from the Late Cretaceous (Turonian, ∼90 million years before present [MYBP]) Raritan (or lower Magothy) Formation of New Jersey. The fossil taxa are represented by flowers at various stages of development, associated fragments of cup-shaped floral receptacles with attached anthers, and isolated anthers. Both taxa have laminar stamens with adaxial thecae and valvate dehiscence. Pollen is boat-shaped and foveolate in anthers associated with Cronquistiflora and spherical with reticulate ornamentation in Detrusandra. Cup-shaped receptacles are externally bracteose in both taxa. The receptacle of Cronquistiflora is broader than the campanulate one of Detrusandra. Cronquistiflora also has more carpels (∼50 in a spiral vs. ∼5 in a whorl or tight spiral). In Detrusandra the carpels are surrounded by dorsiventrally flattened structures (pistillodes?) that are remote from the attachment of the stamens near the distal rim of the receptacular cupule. Detrusandra stigmas are rounded and bilobed, while those of Cronquistiflora, although bilateral in symmetry, are somewhat peltate. The fossil taxa share prominent characters with extant cupulate magnoliids (e.g., Eupomatia, Calycanthus), but also share characters with other magnoliids including Winteraceae. These fossils represent taxa that are character mosaics relative to currently recognized families. Inclusion of these fossils in existing data matrices and ensuing phylogenetic analyses effect changes in tree topologies consistent with their mosaicism relative to modern taxa. But such analyses do not definitively demonstrate the affinities of the fossils other than illustrating that these fossils are generalized magnoliids. Additional analysis of modern and fossil magnoliids is necessary to fully appreciate the phylogenetic significance and positions of these fossil taxa. However, the results of the phylogenetic analyses do introduce the possibility that extinct taxa of Magnoliales with cupulate floral receptacles were transitional between basal angiosperms and those with tricolpate pollen. The fossils provide insights into the timing of evolution of character complexes now associated with coleopteran pollination.  相似文献   

6.
Hybodont remains from the Early Cretaceous of the Basque-Cantabrian Basin (Cantabric Range) in the North of Spain are described for the first time. This assemblage represents a highly diversified shark fauna adapted to different feeding habits. Isolated remains of six hybodont genera, namely Hybodus, Egertonodus, Planohybodus, Lonchidion, Parvodus, and Lissodus, have been recovered and described from the freshwater Vega de Pas Formation in the locality of Vega de Pas (Cantabria, Northern Spain). Most of these taxa are known from the English Wealden, making the shark fauna of the Vega de Pas 1 site the most similar assemblage to English Wealden shark fauna among any other site known in Europe.  相似文献   

7.
The study of 38 samples of aquatic fauna from Venezuela increased the number of known species here from 28 to 66. Fifteen new species for science are described. A list of Copepoda known from the other regions of South America is presented. From this list, it can be said that only 50% of the inland water Copepoda living actually in Venezuela are known.  相似文献   

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10.
Three New Species of the Genus Clostridium   总被引:3,自引:0,他引:3  
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11.
A median nauplius eye is reported for the first time in a platycopid ostracod, a group hitherto considered to be blind. A new species of the platycopid ostracod genus Keijcyoidea is described from coastal rocky marine habitats on the Pacific coast of Japan. Observations of living specimens in the laboratory show that it is capable of burrowing to a depth of several millimeters in sandy sediment, using the first two head appendages (antennulae and antennae) and the furca. Females brooded a maximum of five eggs in the posterior brood space of the carapace. The homologies and phylogenetic implications of the trunk segmentation and limbs are discussed, paying particular attention to the sexually dimorphic fifth and sixth limbs; the copulatory appendages of both sexes are interpreted as being attached to trunk segments T6–T7 (counting from the posterior; T1 = posteriormost segment).  相似文献   

12.
中国新疆石竹属一新种   总被引:1,自引:0,他引:1  
描述了在位于新疆昌吉州境内的南山马鹿(Cervus elaphus)保护区发现的石竹科(Caryophyllaceae)石竹属(Dianthus)植物一新种—南山石竹(Dianthus nanshanicus C.Y.Yang &; L.X.Dong),并描绘了形态图。该新种与瞿麦(Dianthus superbus L.)相近,区别在于: 本新种花冠白色,喉部无丝毛状鳞片,茎单生,瓣片深裂为细条状。雄蕊伸出至花瓣的1/2。花粉圆球形, 外壁具穴状和刺状纹饰。种皮细胞较小近光滑。报道了该种的采集过程、生境以及该种在新疆南天山居群的大小和保护状况,并简单介绍了Dianthus在世界的分布情况。  相似文献   

13.
A new trace fossil, Foersterichnus rossensis igen. nov. and isp. nov., is described from the Coniacian Hidden Lake Formation, James Ross Island, Antarctica. The trace fossil is a trackway comprising straight, or slightly curving, paired rows of elongate to tear-shaped impressions, parallel or slightly inclined to the long axis of the trackway. Foersterichnus is interpreted to be the trackway of a brachyuran decapod crustacean. It occurs in transgressive shallow marine deposits formed above the storm wave base in a shelf setting. Preservation of the trackway may have been linked to a rapid deoxygenation event during drowning that led to cessation of bioturbation allowing preservation of mixed layer trackways.  相似文献   

14.
Abstract: Two taxa belonging to the Trigonioidoidea (Order Unionoida) are described from the Early Cretaceous of Spain. Nippononaia (Paranippononaia) camerana subgen. et sp. nov. is described from the Aptian of the Cameros Basin of the north‐west Iberian Range. Subnippononaia fordi Barker et al., 1997 is described from new material from the Calizas de la Huérguina Formation (Late Barremian) from Las Hoyas and Buenache de la Sierra, Cuenca Province, and Subnippononaia is raised to generic status. The stratigraphy and palaeoenvironment of the Cornago G exposure of the Enciso Group where Nippononaia (Paranippononaia) camerana originates is interpreted as a fresh to brackish water system.  相似文献   

15.
This is the first study of caprellid amphipods from the coast of Papua New Guinea. Several collections from Madang Lagoon (north) and Bootless Bay (south) have been studied. Seven species in seven genera are recorded, of which Pseudoproto papua sp. nov. is described as new to science. The genus Pseudoproto Mayer, 1903 has consisted, so far, of only one species, Pseudoproto fallax Mayer, 1903. Although only a single male has been found of Pseudoproto papua sp. nov., differences in antennae, mouthparts, gnathopod 2 and pereopods 3 and 4 have revealed that it represents a new species of Pseudoproto. Lateral view figures of all species, together with a key to species level for the Caprellidea from Papua New Guinea are also included. Communicated by H.-D. Franke  相似文献   

16.
Azar D  Nel A 《ZooKeys》2011,(130):153-165
Libanopsyllipsocus alexanderasnitsynigen. et sp. n., of Psyllipsocidae is described and figured from the Lower Cretaceous amber of Lebanon. The position of the new taxon is discussed and the fossil is compared to other psyllipsocids. The species represents the earliest record of the family Psyllipsocidae.  相似文献   

17.
记述了锚首虫科Ancyrocephalidae 单殖吸虫中国一新纪录属,一新纪录种,即寄生在裸顶脂鲤Gymmocorymbus ternetzi 鳃上的异锁虫属Diaphorocleidus领圈异锁虫Diaphorocleidus armillatus Jogunoori,Kritsky & Venkatanarasaiah,2004和寄生在玫瑰鲃Barbus conchonius鳃上的指环虫属一新纪录种,捷克指环虫Dactylogyrus ostraviensis Rehulka,1988,并对新纪录属种作了新的形态描述并给出了特征图.  相似文献   

18.
Journal of Ichthyology - A new species of batfish Halieutaea dromedaria sp. n from the waters of Vietnam is described. It differs from other representatives of the genus by the presence of a...  相似文献   

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