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During a stay at the Kirstenbosch Research Centre in Cape Town (South Africa), several groups of Asteraceae were studied. One of these was the genus Marasmodes (tribe Anthemideae). After a careful taxonomic study of additional material, including the first species described by A. P. de Candolle, the author has concluded that eight collections should be considered as new species. These new species are described and their relationships with the most similar species of the genus are discussed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 330–342.  相似文献   

3.
The early Miocene sites of Moruorot and Kalodirr (Kenya, 17.5 Myr) have yielded a rich collection of mammals. New listriodont material from these localities, including a complete skull and a partial mandible, provide long awaited information on cranial features of early bunodont Listriodontinae. The evolution and systematics of the group are highly debated, especially regarding its first representatives. The new material described here sheds light on the differentiation of bunodont Listriodontinae in Africa and clarifies the systematics of the group. The first phylogenetic analysis of the Listriodontinae is here performed and supports close relationships between Kubanochoerus and a clade (Eurolistriodon, Listriodon). Lopholistriodon is the most basal representative of the listriodontine clade. These first results stress the role of the African continent in the biogeographical history of the Listriodontinae. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 653–678.  相似文献   

4.
The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South‐West Pacific is a biodiversity hot spot for these squat lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of squat lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 465–493.  相似文献   

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Prior to the present study, seven species of deep‐sea Chirostylidae (‘squat lobsters’), were known from New Zealand: Gastroptychus novaezelandiae, Uroptychodes spinimarginatus, Uroptychus australis, Uroptychus maori, Uroptychus novaezelandiae, Uroptychus politus, and Uroptychus tomentosus. All species are examined from type material and discussed, original illustrations supplemented, and new records provided where available. Uroptychus maori and Uroptychus novaezelandiae are re‐described. The chirostylid fauna of the Kermadec Islands, a remote group of islands north‐east of New Zealand, is studied. Uroptychus alcocki and Uroptychus scambus are reported for the first time from New Zealand, and six new species of the genus Uroptychus are described. Distributional patterns of New Zealand species are discussed and a key to New Zealand Uroptychus species is presented. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 542–582.  相似文献   

7.
In recent years, the Lower Cretaceous (Aptian) Xiagou Formation has yielded approximately 100 avian partial skeletons, many with soft‐tissue traces, from sites in the Changma Basin of Gansu Province, north‐western China. The most abundant taxon amongst these is the ornithuromorph Gansus yumenensis, but enantiornithines have also been identified in the sample. Here we describe two incomplete, semi‐articulated appendicular skeletons, the first consisting of a partial left pelvic girdle and complete pelvic limb, and the second comprised of a nearly complete right pelvic limb. Both specimens bear characteristics diagnostic of Enantiornithes, and are referred to a new taxon, Qiliania graffini gen. et sp. nov. The exceptional, three‐dimensional preservation of these specimens (compared to the crushed, nearly two‐dimensional condition of most other Early Cretaceous avian fossils) reveals new information regarding enantiornithine anatomy, evolution, and diversity. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 201–219.  相似文献   

8.
Taxa missing large amounts of data pose challenges that may hinder the recovery of a well‐resolved, accurate phylogeny and leave questions surrounding their phylogenetic position. Systematists commonly have to contend with one or two species in a group for which there is little or no material available suitable for recovering molecular data. It is unclear whether these taxa can be better placed using analyses based on morphological data only, or should be included in broader analyses based on both morphological and molecular data. The extinct madtom catfish Noturus trautmani is known from few specimens for which molecular data are unavailable. We included this taxon in parsimony and Bayesian analyses of relationships of madtom catfishes based on a combination of morphological and molecular data. Results indicate that using a combination of morphological and molecular data does a better job at providing a phylogenetic placement for N. trautmani than morphology alone, even though it is missing all of its molecular characters. We provide a novel hypothesis of relationships among Noturus species and recommendations for classification within the group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 60–75.  相似文献   

9.
The genus Probactrosaurus was first established for material discovered by a joint Russian/Chinese expedition to the Chinese autonomous region of Neimongol (Inner Mongolia). Fossils were collected at a site named Maorty (= Maortu). Material attributable to ornithopod dinosaurs was considered sufficiently distinct to permit the definition of two species of the new genus: Probactrosaurus gobiensis and P. alashanicus. The former species was based on a considerable quantity of skeletal material, much of which is still to be found in the collections of the Palaeontological Institute (PIN), Moscow. The latter was based on far less well‐preserved specimens, including a holotype (a posterior skull roof) that can no longer be found in the collections of the PIN and which, along with other materials, was reportedly returned to the Institute of Vertebrate Palaeontology and Palaeoanthropology, Beijing. Some remnants of the original material attributed to P. alashanicus have been located in the PIN collections. Both taxa, established by A. K. Rozhdestvensky, are re‐described using all of the available material collected during the early Sino‐Soviet expeditions. Probactrosaurus alashanicus is considered to be a junior subjective synonym of P. gobiensis. Further comparisons are made with the recently described species Probactrosaurus mazongshanensis Lu, 1997. The latter does not appear to be referable to the genus Probactrosaurus. Probactrosaurus is a gracile ornithopod (ranging between 4 and 6 m in length). The skull is unadorned by any form of cranial crest; however, the premaxillary beak is deflected ventrally and the dentition is similar to that seen in more derived hadrosaurid ornithopods. The postcranial skeleton is notable for its gracility, in particular the elongate forearm and manus, and the retention of a small, conical pollex spine. Systematic analysis suggests that P. gobiensis is a derived non‐hadrosaurid iguanodontian ornithopod and the basal sister‐taxon to the clade Hadrosauridae. The phylogeny of currently known iguanodontians is reviewed. © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society, 2002, 136 , 113–144.  相似文献   

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We describe three new species of the genus Gromia from bathyal and abyssal depths in the Weddell Sea. The new species are characterized by a combination of morphological and molecular criteria. All three species possess a distinct oral capsule and a layer of ‘honeycomb membranes’, which form the inner part of the organic test wall. Both these features are typical of gromiids. Their identification as gromiids is confirmed by analyses of partial small subunit ribosomal DNA (SSU rDNA) gene sequences. Gromia marmorea sp. nov. is a rounded species with a prominent oral capsule and a characteristically mottled appearance. In Gromia melinus sp. nov. , the test surface exhibits a polygonal pattern of ridges, with a layer of clay particles coating the surface between the ridges. Gromia winnetoui sp. nov. represents an elongate morphotype in which the organic test is enclosed within an agglutinated case, a feature previously unknown in gromiids. Phylogenetic analysis using the maximum‐likelihood method revealed that all three species form distinct clades, reflecting the morphological differences among Weddell Sea species, as well as between deep‐water Southern Ocean Gromia and previously described gromiids. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 451–469.  相似文献   

12.
As part of a project investigating diversity in early terrestrial vegetation, new specimens of the enigmatic, non‐embryophyte Nematasketum diversiforme have been described from Lower Devonian strata in the Welsh Borderland to elucidate its affinities and role in the ecosystem. Charcoalified fragments were investigated using scanning electron microscopy. They show for the first time that at least part of the organism possessed an axial organization with a peripheral zone forming a rind. The specimens differ from the closely‐allied Prototaxites by the presence of unevenly thickened tubes, both in well‐defined areas (medullary spots), hypothesized as being the sites of hyphal generation, and in the matrix of wide, smooth‐walled and narrow hyphae. Two specimens that show branching but no unequivocal thickened tubes are best assigned to the prototaxalean complex. The fragments, with longitudinally aligned wide tubes in a matrix of much branched, narrower examples, resemble rhizomorphs and cords of extant basidiomycote fungi and are interpreted as exploratory and translocating organs. Postulated affinities of Prototaxites include algae, fungi and hepatics, with the latter interpreting the fossils as rolled‐up liverwort mats. Our studies on a close ally of Prototaxites show no evidence for hepatic affinity, although similarities with fungal linear mycelial structures. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 1–18.  相似文献   

13.
Protozoan epibionts were found on specimens of the mysid Mysis relicta collected in Lake Lü?iai (Lithuania). These protozoans belong to three genera of ciliates: Vorticella, Dendrosoma and Tokophrya, and were located on the antennae, carapace, appendages and abdomen of the basibiont. The ciliates of the genus Vorticella had a bell‐shaped body, with concave‐type striations and a very long contractile stalk. The stalk joined the body via a truncated and overlapping zone. The macronucleus was J‐shaped, and the contractile vacuole was anterolateral. Only one ciliate species of Vorticella has been found on mysids, although on species other than M. relicta, and this is therefore the first record of Vorticella on M. relicta, and the second on the order Mysidacea. The ciliates of the genus Dendrosoma had an irregular body directly attached to the substrate. Finger‐like actinophores arose from the body, with a bundle of tentacles at their ends. The macronucleus ramified into branches that followed the actinophores. These ciliates were included in the species D. astaci. The presence of this ciliate represents the first record of this genus on Mysis relicta. The ciliates of the genus Tokophrya had a pyramidal body, the apical surface of which showed two conspicuous actinophores, with a short, longitudinally striated stalk joining to the body via a narrow unstriated band. The macronucleus was spherical or ovoid, centrally located, and there was an apical contractile vacuole. Only one previous study has referred to the presence of this genus on Mysis relicta, and the data contained in it were compared with those of the present study. The biometrical data and taxonomical position of the ciliate epibionts was considered.  相似文献   

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Two species of the Devonian herbaceous lycopsid Haskinsia Grierson & Banks, H. hastata Berry & Edwards and H. sagittata Edwards & Benedetto, are reported from the Hujiersite Formation (Givetian–Middle Devonian), Xinjiang, north‐west China. Both species were first described from Venezuela. Haskinsia hastata from Xinjiang has hastate leaves with toothed margins, and a pair of basal narrow lateral segments which curve distally. It is assigned to a new subspecies because of the toothed margins which cannot be demonstrated in Venezuelan material. The scar of the sporangium stalk is observed for the first time in specimens of H. sagittata, on the leaves of which a possible ligule structure is also shown. On the basis of our observations on both Xinjiang and Venezuelan specimens, the diagnosis of Haskinsia is enlarged to accommodate plants whose lamina has entire or toothed margins. The palaeophytogeography of the genus, otherwise known from South and North America, is discussed. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 633–644.  相似文献   

16.
A diverse, new lizard assemblage from the early Oligocene of Belgium is described. The Boutersem railway local fauna is the most species‐rich lizard assemblage yet reported from the European early Oligocene. Four lizard taxa are present: Lacertidae, Anguidae, Scincoidea and Platynota. One new species is described, Folisaurus boutersemensis sp. nov . This fauna provides new insight into the profound turnover that took place during the Eocene/Oligocene boundary in Europe. The new fauna confirms a marked decrease in diversity across the Eocene/Oligocene boundary. Two groups encountered in the European late Eocene became extinct (Iguanidae*, Glyptosaurinae). Estimates of species‐level extinctions range up to 80%. These estimates include members of virtually all the families present in the late Eocene. The relative importance of climate change and biotic interactions in controlling this pattern is discussed, and negative interactions between lizards and new carnivorous mammals are favoured. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 148–170.  相似文献   

17.
Recent revision of the fern diversity of the French Caribbean island of Guadeloupe and its dependencies (Marie Galante, Les Saintes and La Désirade) resulted in the listing of 292 native ferns and club mosses in 28 families and 88 genera, of which eight ferns are endemic to Guadeloupe and 20 taxa are only recorded from the Lesser Antilles. Additionally, 21 species have recently been found to be naturalized. Nineteen new combinations are made and a new hybrid is described. Many types from the Fée collection have been reassessed and a number of names are lecto‐ or neotypified. Studied specimens are cited and localities are provided. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161 , 213–277.  相似文献   

18.
Potwarmus is recorded for the first time in Saudi Arabia. The material comes from the Middle Miocene of the Hofuf Formation at Al‐Jadidah. This species, Potwarmus flynni sp. nov. , is described and compared with all species currently placed in the genera Potwarmus, Dakkamys, Paradakkamys, Vallaris, and some species of ‘Myocricetodon’ (i.e. the so‐called ‘primitive dendromurids’) as well as with two of the most primitive definitive murines (namely Antemus chinjiensis and Progonomys debruijni). Potwarmus flynni sp. nov. differs from the above‐mentioned species in having the anterior part of the m1 strongly reduced. A cladistic analysis provides evidence that this new Arabian taxon is close to Potwarmus primitivus and Potwarmus sp. nov. from Jebel Zelten (Libya), and also that this genus is unlikely to be the sister taxon to Antemus. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 664–679.  相似文献   

19.
New species assignable to the formerly monotypic genus Echinopsyllus (Copepoda, Harpacticoida, Ancorabolidae) are described from the continental slope of Campos Basin off Brazil in the south‐western Atlantic. Echinopsyllus brasiliensis sp. nov. , Echinopsyllus nogueirae sp. nov. , and Echinopsyllus grohmannae sp. nov. differ from Echinopsyllus normani Sars, 1909 in the cephalothorax having two instead of three pairs of lateral processes, first pair of dorsal cephalothoracic processes being smaller than second pair, second pair of dorsal cephalothoracic processes branched, and segmentation and setation of the swimming legs. The discovery of new species of Echinopsyllus extends the distributional range of the genus to the southern hemisphere and is further evidence for the formerly unexpected wide genus‐level distribution of Ancorabolidae in the world's oceans. The phylogenetic position of Echinopsyllus within Ancorabolinae is discussed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 52–78.  相似文献   

20.
The Tertiary anatid fossils (Aves: Anatidae) from Oligocene and Miocene deposits in Australia are described. Most fossils derive from the Late Oligocene – Early Miocene (26–24 Mya) Etadunna and Namba Formations, respectively, in the Lake Eyre and Lake Frome Basins of South Australia. The local faunas from these two formations contain the same suite of anatid species. Two new genera, the oxyurine Pinpanetta, with three new species (Pi. tedfordi, 18 specimens; Pi. vickersrichae, 15 specimens; Pi. fromensis, 20 specimens), and the tadornine Australotadorna, for a large new species known from eight specimens, are established. Three anatid bones from the Waite Formation (c. 8 Mya) at Alcoota, Northern Territory reveal the presence of a tadornine that is neither Australotadorna nor an extant Tadorna species, and an indeterminate duck about the size of Malacorhynchus. Phylogenetic analyses establish Pinpanetta as a basal member of an oxyurine (stiff‐tailed duck) radiation. Oxyurines are found to include the Recent Stictonetta and Malacorhynchus as basal members, along with the fossil taxa Mionetta, Manuherikia, and Dunstanetta, and the traditionally included Recent Oxyura, Biziura, Thalassornis, and Nomonyx. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 411–454.  相似文献   

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