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1.
Morphology of the phosphatic sclerites of the species Mobergella radiolata that come from the Lower Cambrian sections is studied, and the stratigraphic distribution of the species is revised. The sclerite laminated microstructure of this species is described and is shown to be similar to that of some gastropods, bivalves, brachiopods, bryozoans, and corals. The species M. hexactina Skovsted, 2003 and M. sibirica Skovsted, 2003 are shown to be junior synonyms of M. radiolata based on sclerite morphology supported by the results of statistical analysis.  相似文献   

2.
Cambrian bivalves from the Middle East are reported here for the first time. They come from early “Middle Cambrian” and latest “Early Cambrian” limestones of the lower Çal Tepe Formation at the type locality (near Seydi?ehir, western Taurides). The majority of the new findings consists of Pojetaia runnegari Jell, 1980, but a few specimens of Fordilla sp. represent the first report of this genus from “Middle Cambrian” strata. Based on a compilation of the hitherto reported, but mostly revised Cambrian bivalves, the today widely accepted taxa are discussed. The genera Pojetaia Jell, 1980 and Fordilla Barrande, 1881 are critically evaluated, and three valid species are included in Pojetaia: P. runnegari Jell, 1980, P. sarhroensis Geyer and Streng, 1998, and—with limitations—P. ostseensis Hinz-Schallreuter, 1995. Fordilla also includes three species: F. troyensis Barrande, 1881, F. sibirica Krasilova, 1977, and F. germanica Elicki, 1994. The Cambrian genera Tuarangia MacKinnon, 1982, Camya Hinz-Schallreuter, 1995, and Arhouriella Geyer and Streng, 1998 most probably belong to the class Bivalvia. Palaeoecologically, the Cambrian bivalves of the Western Perigondwanan shelf seem to occur in a relatively small window of low-energy, subtidal, open-marine, warm-water conditions on a muddy carbonate ramp or platform with reduced sedimentation rate. The frequently interpreted infaunal mode of life of Pojetaia and Fordilla is questioned by observations of similarly organized modern bivalves. The palaeogeographical distribution of Pojetaia and Fordilla is discussed with respect to their early ontogeny and to differences in the recent state of knowledge on shelly fossils from Cambrian carbonate successions of Perigondwana.  相似文献   

3.
A new species group of the genus Oxyopes Latreille, 1804, including three species (O. heterophthalmus (Latreille, 1804), O. nenilini sp. n., and O. takobius Andreeva et Tystshenko, 1969) is distinguished. The group is characterized by (1) complex lateral apophysis of the palpal tibia of males, (2) absence of modifications of the cymbium and palpal tibia, (3) large chitinized plate of the female epigyna, (4) long copulatory ducts of the female endogyna, involuted around the receptacle. The new species, O. nenilini, is described. The species O. heterophthalmus and O. takobius are redescribed. The new synonyms, O. foliiformis Song, 1991, syn. n. = O. yiliensis Hu et Wu 1989, syn. n. = O. takobius Andreeva et Tystshenko, 1969, are proposed.  相似文献   

4.
The genus Gnezdilovius Meng, Webb et Wang, 2017 is revised. Maculergithus Constant et Pham, 2016, which was described as a subgenus of Gergithus Stål, 1870, is upgraded to a genus. Ishiharanus Hori, 1969 is reinstalled from synonymy with Gergithus and considered a valid name. Two new genera are erected, Ceratogergithus Gnezdilov, gen. n. (type species: Gergithus spinosus Che, Zhang et Wang, 2007) and Ophthalmosphaerius Gnezdilov, gen. n. (type species: Hernisphaerius trilobulus Che, Zhang et Wang, 2006). Hernisphaerius bistriatus Schumacher, 1915, Gergithus carbonarius Melichar, 1906, G. rosticus Chan et Yang, 1994, G. nummarius Chan et Yang, 1994, and G. rotundus Chan et Yang, 1994 are transferred to the genus Epyhemisphaerius Chan et Yang, 1994, Gergithus quinquemaculatus Che, Zhang, Wang, 2007—to the genus Maculergithus, Gergithus chelatus Che, Zhang, Wang, 2007 and G. pseudotessellatus Che, Zhang, Wang, 2007—to the genus Ceratogergithus, Hernisphaerius binocularis Chen, Zhang, Chang, 2014—to the genus Ophthalmosphaerius, and Gergithus robustus hoozanensis Schumacher, 1915—to the genus Gnezdilovius. The male genitalia of Gergithus herbaceus (Kirby, 1891) and Hernisphaerius interclusus Noualhier, 1896 are illustrated for the first time.  相似文献   

5.
Based on Yu.L. Pelman’s lingulid collection and our own material, the Early-Middle Cambrian genus Eoobolus, which was widespread on the Siberian Platform, is revised. The Siberian members of this genus have previously been assigned to Lingulella. Two out of these six members are recognized as valid species: Eoobolus siniellus (Pelman) and E. variabilis (Pelman). Lingulella acuta Pelman and L. linguata Pelman are considered here to be junior synonyms of E. priscus (Poulsen, 1932). The valid species are redescribed and their stratigraphic and geographic ranges are given. A new species, E. pelmani sp. nov., is described. New data on the Eoobolus microornamentation and shell structure are provided.  相似文献   

6.
Terrestrial gastropods occur in many North African localities in Eocene continental deposits. Here we analyse the faunal assemblage from the Hamada de Méridja Formation in southwestern Algeria, dated as Early to Middle Eocene on the basis of charophytes. The assemblage consists of three closely related species that to date have been classified either in the extant Madagascan genus Leucotaenius v. Martens, 1860, or in the SW European Eocene genera Romanella Jodot, 1957 and Vicentinia Jodot, 1957. This is rejected for shell morphological and phylogeographical reasons, and a new classification as Maghrebiola gen. nov. is proposed. Maghrebiola is tentatively placed in the South American family Strophocheilidae, as species from the Early Eocene Itaboraí Basin of Brazil, currently placed in the genus Eoborus Klappenbach and Olazarri, 1970 in the family Strophocheilidae, superfamily Acavoidea, have a very similar shell habitus. This record possibly extends the known geographical range of the Strophocheilidae into the African continent during the Eocene. Immigration of this stock into North Africa during the Cretaceous via a still existing plate connection is assumed. An attribution of Maghrebiola to the African family Achatinidae is unlikely for shell morphological reasons despite certain habitus similarities, although the Priabonian genera Arabicolaria and Pacaudiella from Oman most likely belong into this family, and not to the Vidaliellidae as originally proposed. Possible causes for the very low diversity of the assemblage are mainly unfavourable living conditions, i.e. a relatively dry climate resulting in sparse vegetation and only occasional presence of water bodies, which may have had increased salinities, accounting for the lack of freshwater mollusks. The absence of any competing large gastropods may possibly have facilitated high intraspecific variability leading to sympatric occurrence of three closely related species, due to the animals occupying a wide range of available ecological niches. As the species discussed here have also been attributed to the genera Romanella and Vicentinia in the Vidaliellidae, we provide an appendix with annotated characterisations of most genera of the Vidaliellidae and list the nominal species assigned to them. This family is tentatively placed in the South American superfamily Orthalicoidea; its stock would have similarly immigrated from South America, but have successfully colonized mainly SW Europe, with only one Eocene species [Romanella kantarensis (Jodot, 1936)] recognized in Algeria.  相似文献   

7.
A new genus, Boreomica gen. nov., is established; it comprises small-sized gastropods widespread in the Jurassic of the Russian Plate, the taxonomic position of which was ambiguously treated by previous authors. The new genus is assigned to the family Rissoidae. The species composition and stratigraphical and geographical distribution of the genus and its species are discussed. From the Jurassic of the Russian Plate, Callovian Boreomica exigua (Gerasimov, 1992), the type species of the genus, and Kimmeridgian–Volgian Boreomica undulata (Tullberg, 1881), and members of the genus without species status from the Bathonian and Upper Oxfordian are described. Conchological polymorphism of species connected with their eurybiontic characteristics is discussed. Based on the study of samples of the species B. exigua from different types of facies, two subspecies are recognized, B. exigua exigua and B. exigua arenosa subsp. nov. Finds of gastropods morphologically similar to Boreomica are discussed: Katosira? sp. from Mitta et al., 2004, “Procerithium?” volgense Gerasimov, 1955, “Eulima” pusilla Tullberg, 1881, and “Hudlestonella” caleptra sensu Gerasimov, 1992 are considered. It is concluded that E. pusilla and H. caleptra are unknown zygopleurids, Katosira? sp. is likely a poorly preserved Katosira, and “Procerithium?” volgense is represented by a mixture of several species belonging to different genera: several zygopleurid species, the rissoids Boreomica undulata and Bralitzia. Shells of P. volgense in the P.A. Gerasimov’s collection from the Craspedites nodiger Zone are described as Laevipleura sp.  相似文献   

8.
Hardwood floodplain forests in Slovakia have been traditionally classified within the class Querco-Fagetea, order Fagetalia, alliance Alnion incanae, suballiance Ulmenion. Five main syntaxonomical studies on this topic come from the years 1958–1972 and were published by several authors from different regions. Each author described several new geographically delimited subassociations which were considered to be confined to single lowland region. This resulted in unclear classification scheme of hardwood floodplain forests in Slovakia with numerous floristically poorly differentiated units, especially at the subassociation level. We used 404 relevés ordered to the suballiance Ulmenion in the Slovak national database (http://ibot.sav.sk/cdf/) and analysed the dataset by cluster analysis and detrended correspondence analysis. We distinguished four groups of relevés which represents four subassociations within one association Fraxino pannonicae-Ulmetum: Fraxino pannonicae-Ulmetum caricetosum acutiformis Soó in Aszód 1936 corr. Soó 1964, Fraxino pannonicae-Ulmetum populetosum Jurko 1958 (D?atko 1972), Fraxino pannonicae-Ulmetum carpinetosum (Simon 1957) D?atko 1972 and Fraxino pannonicae-Ulmetum convallarietosum Jurko 1958. Associations Querco pedunculiflorae-Populetum tremuli ?om?ák et Háberová 1979, Arunco-Salicetum capreae Hada? et al. 1969 and Filipendulo-Salicetum capreae Hada? et al. 1969 we propose to exclude from the suballiance Ulmenion.  相似文献   

9.
Re-examination of the late Permian Tunguskagyrus planus Yan, Beutel et Lawrence, 2018 has shown that it does not belong to the family Gyrinidae (Adephaga) but should be placed in the family Triaplidae sensu n. (Archostemata) as a congener to “Triaplussibiricus Volkov, 2013 (Tunguskagyrus sibiricus (Volkov, 2013), comb. n.). Both these Palaeozoic species, in contrast to the Triassic members of Triaplus Ponomarenko, 1977, have no large metacoxal femoral plates and, therefore, would be better placed apart from the Mesozoic representatives of Triaplus (in a different genus). The synonymy of the family names Triaplidae Ponomarenko, 1977 (= Catiniidae Ponomarenko, 1968, syn. n., nom. praeocc., non Catiniidae Bocquet et Stock, 1957 (Crustacaea, Copepoda), = Coleocatiniidae Ponomarenko et Prokin, 2015, syn. n.) is established. Thus, the family now comprises Avocatinus Ponomarenko, 1969, Catinius Ponomarenko, 1968, Catinoides Ponomarenko, 1969, Macrocatinius Ponomarenko, 1969, Triaplus Ponomarenko, 1977, Triassocatinius Ponomarenko, 1969 and Tunguskagyrus Yan, Beutel et Lawrence, 2018.  相似文献   

10.
Data on 15 species of the subgenus Pseudotiorhynchus Magnano, 2004 of the genus Otiorhynchus Germar, 1822 from Kazakhstan, Turkmenistan, and Iran are given. Otiorhynchus lukarevskayae Davidian, sp. n., O. karakalensis Davidian et Savitsky, sp. n., O. konstantini Davidian et Savitsky, sp. n., O. muratovi Savitsky et Davidian, sp. n., O. kopetdagicus Savitsky et Davidian, sp. n., and O. shakhensis Savitsky et Davidian, sp. n. from Turkmenistan, and O. khorasanus Savitsky et Davidian, sp. n. from Iran are described as new to science. A new synonymy is established: Pseudotiorhynchus Magnano, 2004 = Crassorhynchus Magnano, 2004, syn. n. Otiorhynchus iranensis Magnano, 2004 is transferred from the subgenus Protarammichnus Voss, 1960 to the subgenus Pseudotiorhynchus. Lectotype of O. conicirostris Stierlin, 1886 is designated. A key to 15 species of the subgenus Pseudotiorhynchus is given. The new subgenus Microhanibotus Savitsky et Davidian, subgen. n. is established for the new species O. ghilarovi Davidian et Savitsky, sp. n. from the Western Kopet Dagh in Turkmenistan. Microhanibotus subgen. n. is closely related to the subgenera Pseudotiorhynchus, Hanibotus Reitter, 1912 and Nubidanus Reitter, 1912.  相似文献   

11.
The genus Leptodes was erected by Dejean (1834) for a single species, Sepidium boisduvalii Zubkoff, 1833, which is, consequently, the type species by monotypy. Kaszab (1959) established in Leptodes the subgenus Leptodinopsis based on the same type species, Sepidium boisduvalii. Thus the names Leptodes and Leptodinopsis are objective synonyms: Leptodes Dejean, 1834 = Leptodinopsis Kaszab, 1959, syn. n. A new subgenus Mesoleptodes G. Medvedev et Iljina subgen, n. (type species Leptodes semenowi Reitter, 1892) is established for species which Kaszab included in Leptodes s. str. A new species, Leptodes daghestanicus G. Medvedev et Iljina, sp. n., is described from Daghestan.  相似文献   

12.
Ammonites of the genus Spiroceras are described from the Upper Bajocian of the Kyafar River Basin (Karachay-Cherkessia), including macroconchs with preserved apertures and (for the first time in the entire history of the study of Middle Jurassic heteromorphs) microconchs with lateral lappets. The microconchs of S. bispinatum (Baugier et Sauzé), mainly represented by cyrtocones with one ventral row of nodes, correspond to microconchs with a gyroconic shell and a single row of nodes. Macroconchs and microconchs of S. annulatum (Deshayes), the ribs of which lack prominent nodes or spines, are found together. The assemblage also contains small-sized slightly uncoiled shells of Spiroceras aff. S. fourneti Roman et Pétouraud with widely spaced ribs and two prominent rows of large nodes, presumably macro- and microconchs. The ornamentation of this species resembles that of the monomorph Bajocia rarinoda Sturani from the upper part of the Lower Bajocian; perhaps the latter was ancestral to the Middle Jurassic heteromorph. The above species of Spiroceras, as well as S. obliquecostatum (Quenstedt), are figured.  相似文献   

13.
The names of the Cossidae taxa Garuda Yakovlev, 2004 (type species Garuda galina Yakovlev, 2004) and Nirvana Yakovlev, 2004 (type species Nirvana buddhi Yakovlev, 2004) described by the author from various Eurasian regions are substituted by new names due to the former having been previously preoccupied. The name Garuda Yakovlev, 2004: 375 (type species Garuda galina Yakovlev, 2004) is proposed to be substituted for Garrudiella Yakovlev nom. n., since Garuda was used by Scherer (Scherer 1969: 28) while describing a new species in the family Chrysomelidae (Coleoptera) (type species Garuda hindustanica Scherer 1969).  相似文献   

14.
Data on distribution of Lasius neglectus Van Loon et al. in Crimea are reported. The structure of foraging areas of 111 monocalic and polycalic colonies, the daily activity rhythm, and the visiting of 26 species of trees by L. neglectus workers were studied; over a third of the visited tree species were conifers. Most colonies of L. neglectus in Crimea are monocalic. No replacement of the 12 native ant species present in the territories of the monocalic and polycalic colonies of L. neglectus was observed. Invasion of L. neglectus to Crimea probably started in the early 1970s.  相似文献   

15.

Introduction

Chemical industries are constantly in search of an expeditious and environmentally benign method for producing chiral synthons. Ketoreductases have been used as catalysts for enantioselective conversion of desired prochiral ketones to their corresponding alcohol. We chose reported promiscuous ketoreductases belonging to different protein families and expressed them in E. coli to evaluate their ability as whole-cell catalysts for obtaining chiral alcohol intermediates of pharmaceutical importance. Apart from establishing a method to produce high value (S)-specific alcohols that have not been evaluated before, we propose an in silico analysis procedure to predict product chirality.

Results

Six enzymes originating from Sulfolobus sulfotaricus, Zygosaccharomyces rouxii, Hansenula polymorpha, Corynebacterium sp. ST-10, Synechococcus sp. PCC 7942 and Bacillus sp. ECU0013 with reported efficient activity for dissimilar substrates are compared here to arrive at an optimal enzyme for the method. Whole–cell catalysis of ketone intermediates for drugs like Aprepitant, Sitagliptin and Dolastatin using E. coli over-expressing these enzymes yielded (S)-specific chiral alcohols. We explain this chiral specificity for the best-performing enzyme, i.e., Z. rouxii ketoreductase using in silico modelling and MD simulations. This rationale was applied to five additional ketones that are used in the synthesis of Crizotinib, MA-20565 (an antifungal agent), Sulopenem, Rivastigmine, Talampanel and Barnidipine and predicted the yield of (S) enantiomers. Experimental evaluation matched the in silico analysis wherein?~?95% (S)-specific alcohol with a chemical yield of 23–79% was obtained through biotransformation. Further, the cofactor re-cycling was optimized by switching the carbon source from glucose to sorbitol that improved the chemical yield to 85–99%.

Conclusions

Here, we present a strategy to synthesize pharmaceutically relevant chiral alcohols by ketoreductases using a cofactor balanced whole-cell catalysis scheme that is useful for the industry. Based on the results obtained in these trials, Zygosaccharomyces rouxii ketoreductase was identified as a proficient enzyme to obtain (S)-specific alcohols from their respective ketones. The whole–cell catalyst when combined with nutrient modulation of using sorbitol as a carbon source helped obtain high enantiomeric and chemical yield.
  相似文献   

16.
This study investigates changes in body proportions during ontogenesis of the bivalves Astarte arctica and A. borealis from the subtidal zone of northeastern Sakhalin. Marked differences in the shell form of bivalves were found. The shell of A. arctica is convex and compact, shell length and height are comparable, and shell width is more than 50% of shell height. A. borealis has a slightly elongate and flattened shell, its width is less than 50% of its height. Shell proportions can provide a reliable criterion for differentiating the species. Mollusks grow at nearly the same rate but attain different maximum sizes. Linear growth is described by Bertalanffy’s equation: Lt = 48.2[1 ? e ?0.4850(t ? 0.4396)] for A. arctica and Lt = 53.1[1 ? e?0.4106(t ? 0.4253)] for A. borealis. In northeastern Sakhalin, the life span of A. arctica is 7 years and of A. borealis, 8 years. By life span, the two bivalve species from Sakhalin slightly differ from their counterparts in other regions, particularly the arctic seas.  相似文献   

17.
The vulnerability of gastropods to their predators varies with life history traits such as morphology, body size, behavior, and growth rates as well as predator size. A recent study suggested that the invasive apple snail, Pomacea maculata, was considerably more vulnerable to crayfish predators than the native Florida apple snail, P. paludosa. The difference was hypothesized to be caused by the relatively small hatchling size of P. maculata. To test this hypothesis, we conducted a series of feeding assays designed to quantify maximum feeding rates and selective foraging of crayfish on apple snails. The rate at which crayfish killed individual P. maculata (i.e., kill rates) decreased with snail size, and kill rates on both species increased with crayfish size. Kill rates on juvenile P. maculata were higher than kill rates on size-matched hatchling P. paludosa, and crayfish fed selectively on P. maculata when offered mixed groups of size-matched snails. Further analyses revealed that hatchling P. paludosa possess shells 1.8× heavier than size-matched P. maculata suggesting differences in vulnerability to crayfish were consistent with interspecific differences in shell defenses. Differences in hatchling size and defensive traits in combination make crayfish kill rates on hatchling P. maculata approximately 15.4× faster than on hatchling P. paludosa, but the relative contribution of hatchling size to differences in apple snail vulnerability was >3× greater than the contribution of defensive traits.  相似文献   

18.
Gastropods belong to a hyper-diverse clade of molluscs and encompass limpets, slugs and snails. Interestingly, gastropods have effectively colonized land, freshwaters and marine habitats. However, the relationships among and within its constituent taxa remained in flux for decades due to delimitation in their morphological and anatomical features and hence molecular approach has taken a lead. An understanding into the history of Tibetan tectonic terranes is attempted in this article to derive through the phylogeny of Pila. In our study, we have re-evaluated the relationships within Ampullariidae by collecting the species of Pila globosa and Pila virens (India) and analyzed them comparing with 18S rDNA sequences from public domain. Obtained sequences are evaluated through Maximum Likelihood method in MEGA v 5 which clearly established a single cluster for the three individual taxons namely P. globosa with high bootstrap support. Pila virens showed a paraphyletic cluster with Pila ovata. A low bootstrap value of a few species of Pila possibly inferred rapid speciation among them. The novel observation in the present study is that P. virens forming a secondary cluster with the species from Vietnam namely Pila polita, Pila conica and Pila ampullacea has authenticated that the south India and Vietnam are in the same latitude namely 9–20°N, supporting the paleomagnetic data which unravelled that India collided with Asia around 57 mya in the Coenozoic era, whereas ampullariids must have been in co-existence since the Cambrian Period indicating their long evolutionary affinity and zoo-geographical relationship.  相似文献   

19.
This paper continues our revision of Yu.L. Pelman’s collection of the superfamily Acrotheloidea (phosphatic brachiopods) and of our own material from the Early–Middle Cambrian of the Siberian Platform. The following representatives of the superfamily Acrotheloidea (order Lingulida, class Linguliformea) are restudied and revised based on new techniques: the genus Botsfordia (family Botsfordiidae Schindewolf, 1955) and the genera Acrothele, Eothele, and Orbithele (family Acrothelidae), which are widespread on the Siberian Platform. Only one out of the three Acrothele species described by Pelman is recognized as a valid species, and one new species of this genus that comprises some part of the brachiopods that Pelman figured and placed in another taxon is described. All these species are described using data on shell microsculpture and microstructure. In addition, the genera Eothele and Orbithele are described for the first time from the Siberian Platform.  相似文献   

20.
A new opecoelid trematode is reported from fishes of the Lethrinidae, Lutjanidae and Nemipteridae off Lizard Island on the northern Great Barrier Reef, Australia. The new species keys to Neolebouria Gibson, 1976 and shows strong similarity to several species of that genus, but is not consistent with the type-species, N. georgiensis Gibson, 1976, or others known from temperate/polar and/or deep-sea fishes. The new species is also phylogenetically distant from N. lanceolata (Price, 1934) Reimer, 1987, the only representative of the genus for which molecular data are available. A new genus, Trilobovarium n. g., is proposed for the new species, T. parvvatis n. sp. Eight morphologically similar species, previously recognised as belonging to Neolebouria, from shallow-water, mostly tropical/subtropical fishes, are transferred to Trilobovarium: T. diacopae (Nagaty & Abdel Aal, 1962) n. comb.; T. ira (Yamaguti, 1940) n. comb.; T. khalili (Ramadan, 1983) n. comb.; T. krusadaiense (Gupta, 1956) n. comb.; T. lineatum (Aken’Ova & Cribb, 2001) n. comb.; T. moretonense (Aken’Ova & Cribb, 2001) n. comb.; T. palauense (Machida, 2014) n. comb.; and T. truncatum (Linton, 1940) n. comb. Paramanteriella Li, Qiu & Zhang, 1988 is resurrected for five species of Neolebouria with a post-bifurcal genital pore: P. cantherini Li, Qiu & Zhang, 1988; P. capoori (Jaiswal, Upadhyay, Malhotra, Dronen & Malhotra, 2014) n. comb.; P. confusa (Overstreet, 1969) n. comb.; P. leiperi (Gupta, 1956) n. comb.; and P. pallenisca (Shipley & Hornell, 1905) n. comb. Neolebouria georgenascimentoi Bray, 2002, a species with an exceptionally long cirrus-sac, is transferred to Bentholebouria Andres, Pulis & Overstreet, 2004 as B. georgenascimentoi (Bray, 2002) n. comb., and N. maorum (Allison, 1966) Gibson 1976, an unusual species known from cephalopods, is designated a species incertae sedis. Eleven species are retained in a revised concept of Neolebouria.  相似文献   

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