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1.
The loricate choanoflagellate genera Pleurasiga and Parvicorbicula are taxonomically ambiguous. Pleurasiga because of the uncertainty that relates to the true identity of the type species, and Parvicorbicula because too many newly described species over time have been dumped here in lack of better options. While all species currently allocated to the genus Pleurasiga (with the exception of the type species) are observed in our samples from the global warm water belt, the genus Parvicorbicula is represented by just a few and mostly infrequently recorded taxa. Two new species, viz. Pl. quadrangiella sp. nov. and Pl. minutissima sp. nov., are described here. While the former is closely related to Pl. echinocostata, the latter is reminiscent of Pl. minima. Core species of Pleurasiga and Parvicorbicula deviate from the vast majority of loricate choanoflagellates in having both the anterior and the mid-lorica transverse costae located exterior to the longitudinal costae. In Pl. quadrangiella there is no mid-lorica transverse costa but rather a small posterior transverse costa located inside the longitudinal costae. In Pl. minutissima the mid-lorica transverse costa has extensive costal strip overlaps which reveal patterns of costal strip junctions that deviate from the norm.  相似文献   

2.
The ambition to generate an overview of warm water loricate choanoflagellate biodiversity, based on a classic morphometric approach, is here completed by analyses of a range of tiny forms with anterior spines or projections and in most cases also a posterior pedicel. The warm water study complements previously obtained results from the more extensively studied temperate and polar regions of the world’s oceans. It thus contributes to a significantly more balanced approach to global diversity patterns for these organisms. The current survey includes taxa such as Polyfibula elatensis, Parvicorbicula pedicellata, as well as a range of primarily undescribed and taxonomically challenging species, that are in an interim approach allocated to Coronoeca gen. nov. (C. kosmaniae sp. nov., C. conicella sp. nov., C. superpositus (Booth) comb. nov., C. marchantii sp. nov., C. tongiae sp. nov., and C. patongiensis sp. nov.). The analysis of warm water acanthoecid biodiversity has revealed in total 80 species from the six geographic regions sampled, corresponding to approximately 50% of all loricate species described. Nineteen species are previously undescribed forms. The Andaman Sea, Thailand, and West Australia are in a global context the most species-rich regions with 62 and 64 species respectively.  相似文献   

3.
Three species of loricate choanoflagellates (Choanoflagdlida,Acanthoecidae), collected from the Andaman Sea near Phuket Island(SW Thailand), have been described and referred to Apheloeciongen.nov. (holotype: A. quadrispinum sp.nov.). All species possessa single-chambered lorica composed of one transverse costs overlaidby a limited number of longitudinal costae which converge posteriorly.Anteriorly the longitudinal costae protrude above the transversecosta as sharp pointed spines. In A. quadrispinum sp.nov. andA. pentacanthum sp.nov. the lorica is terminated by a shortposterior spine, whereas in A. articulatum sp.nov. the pedicelis much more prominent, consisting of several costal stripswhich are joined end-to-end. The species of Apheloecion appearto be most closely related to species of Calliacantha and Monocosta.None of the species described are so far known from localitiesoutside the Andaman Sea.  相似文献   

4.
The tectiform loricate choanoflagellate genera Calotheca, Stephanacantha and Syndetophyllum have all been first described from warm water habitats and share the presence of flattened and often elaborate costal strips in the lorica. The current reinvestigation does confirm both the widespread occurrence of these taxa within the global warm water belt, and largely corroborates the established genus and species matrix. We describe here Stephanacantha oceanica sp. nov. which closely resembles S. campaniformis, and transfer Parvicorbicula zigzag to the genus Stephanacantha, despite differences in costal strip morphology, but based on a complete agreement in lorica constructional details.  相似文献   

5.
6.
A new species of the fungus weevil genus Glaesotropis is described from the Late Eocene Rovno amber. G. diadiasashai sp. nov. differs from G. weitschati and G. minor described from Baltic amber in having a longer rostrum and in the structure of its antennae, with the third and fourth antennomeres being longer than the first and second ones. Additionally, the new species differs from G. weitschati in being smaller, in having unswollen frons, and weakly and smoothly concave elytral margin near hind coxae. The new species also differs from G. minor in having an uninterrupted posterior transverse carina on the pronotum, elytra less convex longitudinally, and a slightly broadened rostrum at the attachment of antennae.  相似文献   

7.
Chiara Angelone  Lorenzo Rook 《Geobios》2011,44(2-3):151-156
Alilepus meini nov. sp., a new leporid known only from the Early Messinian of central-western Italy (Baccinello-Cinigiano basin, V3 faunal assemblage; Tuscany), is described here. A. meini nov. sp. is an endemic taxon – not inherited from the older Tusco-Sardinian assemblages – of the continental and balanced BCB V3 fauna. The peculiarities of A. meini nov. sp. mainly reside in the occlusal surface of p3 (very large anteroconid, extremely short talonid, deep and crenulated posterior flexids, extremely thin protoisthmus) and P3 (wide hypoflexus). A. meini nov. sp. seems closely related to Alilepus turolensis, as testified by shared morphological characters (globous anteroconid and deep protoflexid, very thin protoisthmus). Palaeobiogeographical evidences support morphological data as A. meini nov. sp. and A. turolensis are the only two species of the genus present in western Europe.  相似文献   

8.
New fossil species, Puncticulata versiformis sp. nov. and Cyclotella kathmanduensis sp. nov., are described from lacustrine sediments in the Kathmandu Basin on the southern slope of the Nepal Himalaya. They were dominant in the Middle Pleistocene. Both LM and SEM observations reveal their unique morphological features. Puncticulata versiformis is characterized by (1) various valve outlines (circular, elliptical, or oval), (2) a tangentially undulate central area, (3) a complex alveolar structure composed of three kinds of costae (thick costae, thin costae, and thin and short costae), (4) well‐developed spines (Y‐shaped and tapering) located on one side of the valve face/mantle area junction, and (5) a valvocopula with an extremely undulate margin. The species‐specific feature of C. kathmanduensis is the presence of two kinds of alveolate zones in a single valve: type‐1 zone composed only of normal costae, and type‐2 zone composed of both normal costae and recessed costae bearing fultoportulae. Changes in valve ornamentation occur in these two species from initial valves to vegetative valves. In P. versiformis, the arrangement of areolae with internal domed cribra and fultoportulae in the central area changes from radial rows in the initial valve to groups in the vegetative valve. In the initial valve of C. kathmanduensis, the type‐1 alveolate zone is generally absent.  相似文献   

9.
This study presents the new fossil material of bovids from the recently discovered upper Miocene locality of Platania, Drama (Greece). The material was excavated from 2012 to 2016 and yielded approximately 760 specimens attributed to hipparions, rhinos, cervids, giraffids, suids, proboscideans, hyaenids, and turtles. The bovid material described here includes six taxa of Antilopinae and one of Bovinae. Antilopines are represented by Gazella sp., Gazella cf. ancyrensis, Prostrepsiceros aff. syridisi, cf. Palaeoreas, Palaeoryx minor nov. sp., and Tragoreas? aff. oryxoides. Bovines are recorded by a single boselaphine attributed to Miotragocerus sp. Departing from other Palaeoryx species, the new species P. minor has rather straight and weakly divergent horn-cores tilted backwards, obtuse facial and occipito-parietal angles, and smaller cranial and horn-core size, though associated with a proportionally large toothrow. Miotragocerus sp. from Platania seems to be conspecific to the Miotragocerus sp. from the end-Vallesian Nikiti-1 fauna (Greece). The bovid assemblage of Platania shows a mix of both Vallesian and Turolian taxa indicating a likely late Vallesian-early Turolian age.  相似文献   

10.
A new genus and species of loricate choanoflagellate, Kakoeca aniarctica Buck & Marchant gen. et sp.n. grown in rough culture from an Antarctic sea ice innoculum is described. This organism has a distinctive lorica morphology consisting of more than 200 costal strips arranged in transverse and longitudinal costae that arc perpendicular to one another in the posterior portion of the lorica. The transverse costae show declination with respect to the lorica axis in the anterior part of the lorica. The cell is suspended in the lorica by a robust protoplast suspensory membrane. This membrane blocks water flow from the posterior of the lorica necessitating water entry through the side of the lorica, an area where the maximum sized apertures in the lorica are found. Terminology (lorica lining and protoplast suspensory) is suggested for the two types of lorica membranes which have been found associated with loricas.  相似文献   

11.
12.
Three new acanthoecidaean species collected from the coastal waters of Taiwan and Japan are described: Acanthocorbis camarensis n. sp. resembles Acanthocorbis unguiculata in lorica morphology, but differs in having regularly arranged longitudinal and transverse costae at the anterior lorica chamber, and in lacking a nail at the apical end of anterior spine; Diaphanoeca spiralifurca n. sp. is characterized by the spiral arrangement of the costal strips in the posterior half of the lorica chamber and is closely related to Diaphanoeca grandis; Stephanoeca supracostata n. sp. is closely related to Stephanoeca elegans, but differs in having an additional transverse costa at the anterior lorica chamber.  相似文献   

13.
The choanoflagellate genus Cosmoeca gen.n. is characterized by a very regular arrangement of rod-shaped costal strips, forming 9–12 longitudinal costae (each composed of 34 costal strips) and 2–3 transverse costae. Anteriorly the longitudinal costae attach the transverse costae at the joints between neighbouring transverse costal strips. Five species of Cosmoeca are described: norvegica sp.n. (type species; previously referred to as sp. "N"), C. ventricosa sp.n., (C. phuketensis sp.n., C. subulata sp.n. and C. ceratophora sp.n. Cosmoece ventricosa sp.n. is obviously part of from complex, the extent of which has not yet been fully explained. In this paper, three groups of specimens clearly related to C. ventricosa sp.n. are illustrated and briefly described ( C. ventricosa forms A. B, C). Form A appears to be identical to Pleurasiga orculaeformis Schiller, 1925, sensu Leadbeater.  相似文献   

14.
Microfacies analyses performed on the latest Permian Wujiaping Formation at Laren (Guangxi Province, South China) show that the bioclastic-rich limestones of Late Permian age contain a rich and well-diversified foraminiferal fauna. This fauna is here revised in order to be compared with time-equivalent levels of southern Iran and southern Turkey. Some new and unexpected phylogenetic trends are highlighted among the biseriamminoids. The new or poorly known genera Retroseptellina, Septoglobivalvulina, Paraglobivalvulinoides, Dagmarita?, Bidagmarita nov. gen., Louisettita, Paradagmaritopsis nov. gen. and Paradagmarita? are concerned. Nevertheless, these newly appeared biseriamminoids are subordinate to abundant Tetrataxis and Climacammina, ultimate survivors of the families Palaeotextulariidae and Tetrataxidae, appeared as old as the Early Carboniferous (“Mississippian”). Algae, miliolids, and nodosarioids are poorly represented. Two genera and four species are here newly described: Globivalvulina curiosa nov. sp., Louisettita ultima nov. sp., Bidagmarita nov. gen., Bidagmarita sinica nov. gen. nov. sp., Paradagmaritopsis nov. gen., Paradagmaritopsis kobayashii nov. gen. nov. sp. The palaeogeographic distribution of these foraminifers is interpreted to be typically of Neo-Tethyan regions, ranging from southern Turkey (Hazro) to South China (Laren) and up to Japan for some species (i.e., Paradagmaritopsis). At Laren, Late Permian strata are generally characterized by Reichelina ex gr. simplex Sheng. Isolated samples of packstones, collected in Tsoteng region (Guangxi Province, South China), contain Sphaerulina sp. together with various smaller foraminifers and numerous representatives of the new species G. curiosa nov. sp. In this study we demonstrate that the regions of Zagros (Iran), Taurus (Turkey), South China and even Japan shared similar foraminiferal assemblages and represented intermittently connected palaeobiogeographic provinces during Late Permian times.  相似文献   

15.
Until recently acanthoecid choanoflagellates have been described only from marine and brackish waters. Here I describe a distinct, strictly freshwater acanthoecid species from Samoa based on its morphology, ecology and molecular biological data (partial Small Subunit rDNA). The lorica of the species is characterised by two extensions at the posterior chamber which are used for attachment to the substratum. The posterior chamber is constructed of irregularly arranged costae. The anterior chamber consists of four transverse costal rings and 14–18 longitudinal costae. Despite its sturdy appearance, the lorica was extremely sensitive to water turbulence and movements of the water. The species showed a salinity tolerance of 0.5 practical salinity units with reduced growth rates and a temperature tolerance range of 20–34 °C. According to the morphology, phylogenetic analysis, and autecology of the species it was classified as a member of the genus Stephanoeca.  相似文献   

16.
Well-preserved palynomorph assemblages are recovered from the Devonian Jauf and Jubah formations in five shallow boreholes in the northern part of Saudi Arabia. These fully cored boreholes overlap stratigraphically to form a 1640 ft composite sequence. Miospores dominate the palynological assemblages of most samples. The assemblages are mainly composed of trilete spores but also contain cryptospores and monolete spores. One new genus, sixteen new species and two new varieties of miospores are described from the studied assemblages: Artemopyrainconspicua nov. sp., Artemopyrarecticosta nov. sp., Camarozonotriletesfilatoffii nov. sp., Camarozonotriletesrugulosus nov. sp., Cymbohilatesbaqaensis nov. sp., Cymbohilatescomptulus nov. sp., Cymbohilatesheteroverrucosus nov. sp., Cymbosporitesasymmetricus nov. sp., Dibolisporitespilatus nov. sp., Dictyotriletesbiornatus nov. sp., Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. divellomedia, Gneudnasporadivellomedia (Chibrikova) Balme, 1988 var. minor nov. var., Latosporitesovalis nov. sp., Scylasporacostulosa nov. sp., Squamisporaarabica nov. gen. and sp., Stellatisporamulticostata nov. sp., Zonotriletesarmillatus nov. sp. and Zonotriletessimplicissimus nov. sp. Their stratigraphic distribution is compared to the well-established Devonian West European zonation of Streel et al. (1987) (Streel, M., Higgs, K.T., Loboziak, S., Riegel, W., Steemans, P., 1987. Spore stratigraphy and correlation with faunas and floras in the type marine Devonian of the Ardenne-Rhenish region. Review of Palaeobotany and Palynology 50, 211-219). A late Pragian-Givetian age is suggested for this sequence. No characteristic Eifelian taxa are recorded, but this could be explained by a gap in palyniferous samples.  相似文献   

17.
A palynofloral assemblage is described from the Upper Triassic Dockum Group of Texas. Forty palynomorph species are recorded and these are correlated with European Upper Triassic assemblages. The Dockum Group assemblage is considered to be of late Karnian age.Two new genera, Tulesporites gen. nov., type species T. briscoensis sp. nov., and Daughertyspora gen. nov., type species D. chinleanus (Daugherty) comb. nov. have been erected; new species are Converrucosisporites matsenii sp. nov., Pyramidosporites traversei sp. nov., Callialasporites triassicus sp. nov., Plicatipollenites minutotriletus sp. nov., Triadispora dockumensis sp. nov., Bhardwajispora jansonii sp. nov., Protodiploxypinus americus sp. nov., P. ujhelyi sp. nov., Klausipollenites gouldii sp. nov., Pityosporites old-hamensis sp. nov., Abietineaepollenites bujakii sp. nov., Falcisporites oviformis sp. nov. and F. tecovasensis sp. nov.  相似文献   

18.
Pelliales is a basal lineage of the simple thalloid liverworts. Here, we describe a simple thalloid liverwort from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region in northwestern China. The thalloid fossil liverwort is described as a new species: Pellites hamiensis (Pelliaceae, Pelliales). Pellites hamiensis nov. sp. resembles the extant species of Pelliaceae in having ribbon-like segments, conspicuous costae that appear as ridges on the ventral surface, rectangular cells with thickened walls adjacent to the margin, and elongated cells in the middle part of the thallus. The occurrence of P. hamiensis nov. sp. extends the fossil records of Pellites back to the Aalenian-Bajocian or Bajocian (ca. 170 Ma) and suggests that the divergence time of the Pelliaceae is no later than the Middle Jurassic.  相似文献   

19.
《Journal of Asia》2006,9(4):327-337
As the first part of the taxonomic review for the Lecithoceridae in the northern part of Vietnam, 14 species belonging to the subfamily Torodorinae are recognized, including five new species. We describe three species of the genus Torodora Meyrick (T. phamae sp. nov., T. bachmaensis sp. nov., T. nabiella sp. nov.), two species of Antiochtha Meyrick and Thubana Walker (A. angustivalva sp. nov. and T. circularis sp. nov.) respectively. A taxonomic review for all known species of the subfamily in Vietnam is provided, with illustrations of the imago and genitalia for the species.  相似文献   

20.
《Comptes Rendus Palevol》2007,6(5):311-319
One new foraminiferal genus, Rectoformata gen. nov., with two new species, has been described from a Permian limestone block in the Karakaya Complex in the South of the Balya district (Balikesir, northwestern Turkey). The type species of Rectoformata, Rectoformata tekini sp. nov., is characterized by a quadrangular transverse section having a calcareous microgranular wall with fine alveolar structures, whereas Rectoformata acari sp. nov. is recognized by a pentagonal transverse section having a calcareous microgranular wall with fine alveolar structures. The age of the described taxa is assigned as Midian ( = Capitanian) based on the association with small foraminifers and fusulinids. These new taxa are included in the family Chitralinidae, which is emended herein.  相似文献   

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