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1.
《Palaeoworld》2023,32(2):333-353
A new late Katian (Late Ordovician) trilobite association is documented from the Daduhe Formation in Zhenxiong, northeastern Yunnan, including 17 species of 15 genera, among which four species (Malongullia sinensis, M. zhenxiongensis, Taklamakania paucisegmentatus and Amphitryon constrictus) are new. Lithologic and faunal evidence enables the recognition of a new association with medium diversity, named the Taklamakania Association. It is a typical representative of the Raphiophorid Community that lived in a deep subtidal environment close to the anoxic basin. A total of five trilobite ecological associations were found to occur in South China during the late Katian, in relation to the environmental gradients ranging from shallow subtidal zone, deep subtidal zone, slope to dysoxic shaly basin.  相似文献   

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三叶虫是寒武纪演化动物群中最引人注目的成员之一,其内部解剖结构一直以来受到广泛关注.与其他非生物矿化软体结构相比,三叶虫的消化系统更容易留下化石记录,为探索其内部结构提供了难得的机会.本文描述了来自山东省潍坊市寒武系馒头组的Proasaphiscus,Lioparia,Deiradonyx和Iranoleesia,以及...  相似文献   

3.
A new lichid trilobite belonging to the subgenusMephiarges is described from delicately silicified fragments present in a massive Middle Devonian limestone in South-eastern Australia. Previously this subgenus was limited to one species of which only the cephalon is known.  相似文献   

4.
A moderately diverse Early Devonian (Lochkovian) trilobite and brachiopod association has been recovered from the lower part of the volcano-sedimentary Shakshagaily Formation, exposed on the western side of Lake Balkhash in central Kazakhstan. Its discovery demonstrates the presence of Lower Devonian marine deposits in the region. The trilobite assemblage includes representatives of six genera: the dalmanitid Kasachstania alperovichi nov. sp. is the dominant taxon, with other components being Ananaspis?, Leonaspis?, Maurotarion, Trimerus (Edgillia), and Warburgella. Associated brachiopods include species of Glossoleptaena, Leptaena, Protolepstostrophia, Pseudostrophochonetes, and Resserella. Whilst a significant proportion of these taxa show distinct links with the contemporaneous trilobite and brachiopod faunas of the north Balkhash Region, the occurrence of Trimerus (Edgillia) aff. kinglakensis Gill, 1949 suggests a possible link with the Lochkovian trilobite fauna of the Australasian sector of Gondwana. The west Balkhash Region preserves an extensive record of late Silurian to Early Devonian island arc volcanism, slope-rise sedimentation and olistostrome formation, which has invariably been ignored in models favouring early amalgamation of the Kazakhstanian terranes into a single continent by the end of the Ordovician.  相似文献   

5.
During the larval development of the subantarctic king crab, Lithodes santolla, and stone crab, Paralomis granulosa, we compared changes in the carbon, fatty acid and protein contents of larvae reared under constant conditions from hatching to metamorphosis, either in presence or absence of food (Artemia spp. nauplii). In both species the feeding condition had no influence on any of the chemical parameters studied, indicating a fully lecithotrophic (i.e. non-feeding) mode of development from hatching of the first zoea to metamorphosis of the late megalopa. Dry mass and carbon contents at hatching were similar in the larvae of both species, but L. santolla contained initially higher total amounts of fatty acids and protein than P. granulosa. Both species utilized considerable portions of their total fatty acid pool which decreased logarithmically throughout the time of development. At metamorphosis, it was almost exhausted in P. granulosa, while L. santolla had consumed only about 60%. Protein utilization, in contrast, was higher in L. santolla (40%) than in P. granulosa (20%). Triacylglycerol was the principal storage lipid in both species, accounting initially for about 75% of the lipid fraction; it was strongly utilized during larval development. Phospholipid constituted the second largest lipid class; it also decreased in P. granulosa, but to a lesser extent in L. santolla. The major fatty acids of both species were 18:1(n−9), 20:5(n−3) and 16:0 as well as, in lower proportions, 18:1(n−7), 22:6(n−3), 16:1(n−7) and 18:0. Monounsaturated fatty acids represented the dominant group in L. santolla, whereas P. granulosa contained similar amounts of mono- and polyunsaturated fatty acids. In L. santolla, monounsaturated fatty acids, especially 16:1(n−7), were preferentially utilized as compared to polyunsaturates. Due to a particularly strong lipid utilization in P. granulosa, all individual fatty acids were largely depleted at metamorphosis, showing similar extents of consumption. L. santolla had higher initial lipid and protein stores that seem to be used more economically as compared to P. granulosa.  相似文献   

6.
《Palaeoworld》2014,23(3-4):336-356
Lauraceae is among the largest and floristically most important woody plant families in subtropical and tropical zones. However, the Cenozoic fossil records of Lauraceae are mostly from mid-latitude regions. Here we described eight lauraceous species from the Oligocene of Ningming, Guangxi, South China on the basis of leaf compressions with cuticular structure, providing new evidence for high diversity of Lauraceae in the low latitude region of the northern hemisphere during the late Paleogene. The extant genera to which the Ningming Oligocene fossils are possibly closely related include Cinnamomum, Neolitsea, Litsea, Alseodaphne, Laurus, and Beilschmiedia. All of these extant genera except Laurus still exist in Guangxi today, whereas Laurus is currently distributed in the Mediterranean and adjacent regions. A cladistic analysis based on leaf architectural and leaf cuticular characters for Paleogene Lauraceae species in the world indicated a possible relationship between European and East Asian Paleogene species.  相似文献   

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Several species of Orchidaceae, one of the largest plant families, are considered endangered throughout South America and legal protection policies are needed so they can be preserved. Inter simple sequence repeats (ISSRs) markers are a potential tool to be used in the phylogenetic reconstruction of closely related species. In this study, we evaluate the polymorphic information content (PIC) and optimum number of ISSR markers (ONM) for five Laeliinae orchids in order to assess genetic diversity. The phylogenetic relationships between Cattleya granulosa, an endangered Brazilian orchid, and four other native Brazilian species (Brassavola tuberculata, Cattleya bicolor, Cattleya labiata and Cattleya schofieldiana) were analyzed for genetic diversity and differentiation. The 11 selected primers generated 166 unambiguous loci (PIC = 0.354; ONM = 156). Of the five studied species, C. bicolor exhibited the highest level of genetic diversity (H E  = 0.219), while C. labiata exhibited the lowest level (H E  = 0.132). The percentage of genetic variation among species (analysis of molecular variance) was 23.26 %. The principal component analysis (PCA) of ISSR data showed that unifoliate and bifoliolate species are genetically divergent. Additionally, PCA indicated a close relation between C. granulosa and C. schofieldiana, a species considered to be a variety of C. granulosa by many researchers. Thus, we conclude that ISSR genetic markers are effective in detecting genetic differentiation among orchid species.  相似文献   

10.
Esteve, J., Zamora, S., Gozalo, R. & Liñán, E. 2010: Sphaeroidal enrolment in middle Cambrian solenopleuropsine trilobites. Lethaia, 10.1111/j.1502‐3931.2009.00205.x Fifty specimens belonging to species of Solenopleuropsis and Pardailhania from Spain and France demonstrate sphaeroidal enrolment in Cambrian trilobites for the first time. These solenopleuropsines show novel coaptative structures in different regions of the exoskeleton: in the cephalon there are vincular furrows and notches; in the thorax an articulating facet is developed at the pleural margins, with a ball and socket connection on the adaxial most portion, and an articulating half‐ring axially; the pygidium possesses an articulating facet. The interaction of these coaptative structures resulted in a sphaeroidal enrolment that was a progressive act from the first articulation between the occipital ring and the first segment to the pygidial articulating facet. A similar type of sphaeroidal enrolment is observed in the Devonian trilobite Phacops. Both Cambrian and Devonian trilobites developed a vincular furrow in the ventral surface of the cephalon to close their bodies tightly. In both cases, this is probably a convergent adaptation to protect against predators and obrution. Indeed, the enrolled trilobites are very common in obrution deposits restricted to shallow and soft muddy substrates. □Coaptative structures, convergence, Murero Formation, Pardailhania, Solenopleuropsinae, Solenopleuropsis.  相似文献   

11.
In this study, the findings of three water mite species of the family Hygrobatidae collected from different streams in Turkey were evaluated. Hygrobates (s. str.) anatolicus Esen & Pešić, sp. n. is described as new for science. Hygrobates (Rivobates) diversiporus Sokolow, 1927 and Atractides (s. str.) nikooae Pešić, 2004, which were illustrated and thoroughly discussed, are new records for the Turkish fauna.  相似文献   

12.
A new species of Hispanotherium from the Early Miocene of Spain is named. Its phylogenetic relationships within Elasmotheriina are discussed owing to a cladistic analysis. H. grimmi Heissig, 1974 and H. beonense Antoine, 1997 are consequently integrated in the genus Hispanotherium, together with the type species H. matritense and the new species, which differs from other ones by several dental and postcranial features. The westward dispersal of the Elasmotheriina from Asia toward Western Europe during the Early Miocene is hypothesized. To cite this article: P.-O. Antoine et al., C. R. Palevol 1 (2002) 19–26.  相似文献   

13.
The Furongian trilobite family Tsinaniidae is characterized by a highly effaced surface and forms an important constituent of the Furongian trilobite faunas of east Gondwana. However, the origin of the characteristic morphology of this family has remained unclear. Only recently has the tsinaniid trilobite Lonchopygella megaspina been suggested to represent an intermediate stage in the evolutionary transition to other tsinaniids on the basis of the trunk segmentation. Here, we report successive occurrences of four species of the kaolishaniid genus Mansuyia and a tsinaniid trilobite Tsinania canens from the Furongian (late Cambrian) Chaomidian Formation in Shandong Province, China. A cladistic analysis including these taxa reveals that the four species of Mansuyia constitute stem‐group taxa to the family Tsinaniidae, rendering Mansuyia and the Kaolishaniidae paraphyletic. The youngest species of Mansuyia, M. taianfuensis, turns out to be the immediate sister taxon of the Tsinaniidae, displaying a closely similar morphology to the tsinaniid trilobite, Shergoldia laevigata. The generic and familial boundary therefore situated between M. taianfuensis and S. laevigata.  相似文献   

14.
Ether extracts of Colubrina granulosa heartwood yield the polyphenolic coumaranone maesopsin and 3 pentacyclic triterpene acids of the lup-20(29)-en-28-oic acid group, alphitolic, betulinic and ceanothic acids. Two new compounds, granulosic and colubrinic acids, which belong to a very small class of A ring contracted triterpenes were also isolated. The co-occurrence of maesopsin, alphitolic, betulinic and ceanothic acids suggests that C. granulosa (from Panama) may be closely related or identical to the Australian species, Alphitonia whitei, in which these relatively rare compounds also occur.  相似文献   

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Being an endemic and endangered fish species in Anatolia, P. anatolicus restricted to Lakes Akgöl, Bey?ehir, Çavu?cu, Akkaya Dam and Ere?li marshes as well as some other small marshes in Central Anatolia region, Turkey. Current population of P. anatolicus tends to decrease in the habitats. A detailed study of current population status, biology, ecology and life history of P. anatolicus is required. It should also be included into national threatened fish category.  相似文献   

17.
Didier Merle 《Geobios》2005,38(4):505
Jsowerbya, nov. gen. (Gastropoda: Muricidae) includes three species from the Eocene of the Paris and Hampshire basins. It increases the number of extinct muricid genera, which curiously represent a very small fraction of the described genera. The species of Jsowerbya, often mistaken for the muricopsine genus Muricopsis, possess a unique combination of characters shared with the subfamilies Ocenebrinae and Ergalataxinae. A cladistic analysis, based on structural homologies of the spiral sculpture, however, suggests that Jsowerbya is closely related to the Ocenebrinae. Thus, Jsowerbya is here regarded as one the most basal Ocenebrinae.  相似文献   

18.
Three hundred protaspid and meraspid specimens of the trilobite species Alueva undulata Sdzuy, 1961 from the uppermost Bilbilian limestones of the Valdemiedes Formation (Iberian Chains, NE Spain) have been released by the action of acid. A pædomorphocline is proposed embracing the different species of Alueva, based on the comparison of the ontogenic patterns of the species Alueva undulata Sdzuy, 1961, and the adult morphologies of Alueva moratrix (Sdzuy, 1958). This analysis suggests that the species Alueva? hastata (Sdzuy, 1958) is not related to the pædomorphocline, and provides an approach for evaluating the phylogenetic relationships between the species A. undulata and A. moratrix, which occur across the Lower-Middle Cambrian transition in the Iberian Chains, directly linked with the Valdemiedes event.  相似文献   

19.
In order to determine the phenotypic associations of four morphologically similar species of Microtus occurring in Turkey, we applied landmark-based shape analysis. The skulls of Microtus anatolicus, M. dogramacii, M. guentheri and M. levis (= M. rossiaemeridionalis) were found to differ significantly in terms of both size and shape. M. guentheri had the biggest skull, while M. levis had the smallest. Sexual dimorphism was found in the shape of the skull in M. dogramacii and M. levis. The tympanic bulla area is enlarged in M. anatolicus compared to the other species. Mahalanobis distances (the distance between a point and the group mean, taking into account the within-group covariance-variance matrix) confirm the distinction of the arvalis group (M. levis) and socialis group (Microtus anatolicus, M. dogramacii, M. guentheri).  相似文献   

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