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1.
A preparation of lysozyme from a freshwater bivalve, Unio pictorum, has been isolated by sorption to chitin, and its physicochemical properties have been studied. An assessment of the sensitivity of 48 strains of rhodococci, belonging to the species Rhodococcus rubber, R. luteus, and R. erythropolis (Specialized Collection of Alkanotrophic Microorganisms of the Institute of Ecology and Genetics of Microorganisms, Ural Division of the Russian Academy of Sciences), which were isolated from diverse natural waters, to lysozyme of the mollusk Unio pictorum demonstrated that the three species differ in their sensitivity to its effects. The high resistance of rhodococci to lysozyme is indicative of their considerable permanence in hydrobiocenoses (and, therefore, ability to maintain self-purification of microbiocenoses from hydrocarbons).  相似文献   

2.
Abstract: The two odontocete taxa Squalodon grateloupii and Patriocetus ehrlichii, both the type species of their respective genera, have been at the centre of a great deal of taxonomic confusion. Originally regarded to be conspecific, these two taxa have been the subject of a bewildering taxonomic debate lasting for more than a century, which recently led to the suggestion to abandon these widely used names and replace S. grateloupii with the similar, yet independently and later proposed name S. gratelupi as the type species of Squalodon. Here, we attempt to summarise the events leading to the current confused situation in the hope of resolving this issue once and for all and argue that the name Squalodon grateloupii, as originally proposed, should be reinstated.  相似文献   

3.
In this nomenclatural-historical account of the genera of the Conocardioidea (Mollusca: Rostroconchia) several inconsistencies and errors in the taxonomy and nomenclature of the Conocardioidea are clarified.Cardium aliforme J. de C.Sowerby, 1827, is recognised as type species of the genusConocardium Bronn, 1835, according to the ICZN 4th edition. Based on subsequent incorrect spelling which is in prevailing use, the spellingC. aliforme takes precedence overC. alaeforme andC. aliformis. Further nomenclatural difficulties concerning the generaHippocardia Brown,Pleurorhynchus Phillips,Lichas Steininger andRhipidocardium Fischer are settled. All genus group names and all higher taxa of the Conocardioidea until 2003 are checked from a nomenclatural point of view. The order name Conocardioida is emended herein into Conocardiida as originally used byNeumayr and because it does not conform with Latin grammar.   相似文献   

4.
The phylogenetic relationships and generic assignments of ‘Ochlerotatus’ and related taxa of uncertain taxonomic position in the classification of Aedini previously proposed by the authors in 2004 and 2006 are explored using 297 characters from eggs, fourth‐instar larvae, pupae, adults and immature habitat coded for 158 exemplar species. The ingroup comprises 54 species and the outgroup includes four non‐aedine species and 100 aedine species, 21 of which were previously classified as incertae sedis. Data are analysed in a total‐evidence approach using implied weighting. The analysis produced 158 most parsimonious cladograms. The strict consensus tree (SCT) corroborates the monophyly of the 30 generic‐level taxa recognized previously that are included in the analysis. Overall, the results show remarkable congruence with those obtained previously despite differences in the taxa and morphological characters analysed in this and the two previous studies. All species of Ochlerotatus s.s., subgenus ‘Ochlerotatussensu auctorum, Geoskusea, Levua, Pseudoskusea and Rhinoskusea included in the analysis fall within a single clade that is treated as genus Ochlerotatus; thus, the last four taxa are restored to their previous subgeneric rank within this genus. Nine additional subgenera, of which four are new, are proposed for monophyletic clades of Ochlerotatus species based on the strength of character support and application of the principle of equivalent rank. Acartomyia stat. nov. , Culicelsa stat. nov. , Gilesia stat. nov. , Protoculex stat. nov. and Chrysoconops stat. nov. are resurrected from synonymy with Ochlerotatus; and Empihals subgen. nov. (type species: Culex vigilax Skuse), Pholeomyia subgen. nov. (type species: Aedes calcariae Marks), Buvirilia subgen. nov. (type species: Aedes edgari Stone & Rosen) and Sallumia subgen. nov. (type species: Aedes hortator Dyar & Knab) are described as new. The sister group of Ochlerotatus includes a number of species that were previously regarded as incertae sedis in ‘Oc. (Finlaya)’ and ‘Oc. (Protomacleaya)’. Based on previous observations, refined relationships and new character support, three additional genera are recognized for species previously included in ‘Finlaya’, i.e. Danielsia stat. nov . (type species: Danielsia albotaeniata Leicester), Luius gen. nov. (type species: Aedes fengi Edwards) and Hopkinsius gen. nov. (type species: Aedes ingrami Edwards). Additionally, Alloeomyia subgen. nov. (type species: Culex pseudotaeniatus Giles) and Yamada subgen. nov. (type species: Aedes seoulensis Yamada) are introduced as subgenera of Collessius and Hopkinsius, respectively. As is usual with generic‐level groups of Aedini, the newly recognized genera and subgenera are polythetic taxa that are diagnosed by unique combinations of characters. The analysis corroborates the previous observation that ‘Oc. (Protomacleaya)’ is a polyphyletic assemblage of species. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 29–114.  相似文献   

5.
Summary Albosynnema with the type species,A. elegans, andSolheimia with the type species,S. costaspora, are described as new synnematous taxa. A species ofNegeriella, N. panamensis, is described as new. All of these new taxa produce phragmospores. In addition, new distribution records forCalostilbella Calostilbe, Stromatographium stromaticum, Vrikshopama swetasakha, andIsaria tenuipes are listed.This study was supported by a grant from the National Science Foundation (GB-2433).  相似文献   

6.
7.
The phylogeny and classification of tribe Aedini are delineated based on a cladistic analysis of 336 characters from eggs, fourth‐instar larvae, pupae, adult females and males, and immature stage habitat coded for 270 exemplar species, including an outgroup of four species from different non‐aedine genera. Analyses of the data set with all multistate characters treated as unordered under implied weights, implemented by TNT version 1.1, with values of the concavity constant K ranging from 7 to 12 each produced a single most parsimonious cladogram (MPC). The MPCs obtained with K values of 7–9 were identical, and that for K = 10 differed only in small changes in the relationships within one subclade. Because values of K < 7 and > 10 produced large changes in the relationships among the taxa, the stability of relationships exemplified by the MPC obtained from the K = 9 analysis is used to interpret the phylogeny and classification of Aedini. Clade support was assessed using parsimony jackknife and symmetric resampling. Overall, the results reinforce the patterns of relationships obtained previously despite differences in the taxa and characters included in the analyses. With two exceptions, all of the groups represented by two or more species were once again recovered as monophyletic taxa. Thus, the monophyly of the following genera and subgenera is corroborated: Aedes, Albuginosus, Armigeres (and its two subgenera), Ayurakitia, Bothaella, Bruceharrisonius, Christophersiomyia, Collessius (and its two subgenera), Dahliana, Danielsia, Dobrotworskyius, Downsiomyia, Edwardsaedes, Finlaya, Georgecraigius (and its two subgenera), Eretmapodites, Geoskusea, Gilesius, Haemagogus (and its two subgenera), Heizmannia (and subgenus Heizmannia), Hopkinsius (and its two subgenera), Howardina, Hulecoeteomyia, Jarnellius, Kenknightia, Lorrainea, Macleaya, Mucidus (and its two subgenera), Neomelaniconion, Ochlerotatus (subgenera Chrysoconops, Culicelsa, Gilesia, Pholeomyia, Protoculex, Rusticoidus and Pseudoskusea), Opifex, Paraedes, Patmarksia, Phagomyia, Pseudarmigeres, Rhinoskusea, Psorophora (and its three subgenera), Rampamyia, Scutomyia, Stegomyia, Tanakaius, Udaya, Vansomerenis, Verrallina (and subgenera Harbachius and Neomacleaya), Zavortinkius and Zeugnomyia. In addition, the monophyly of Tewarius, newly added to the data set, is confirmed. Heizmannia (Mattinglyia) and Verrallina (Verrallina) were found to be paraphyletic with respect to Heizmannia (Heizmannia) and Verrallina (Neomacleaya), respectively. The analyses were repeated with the 14 characters derived from length measurements treated as ordered. Although somewhat different patterns of relationships among the genera and subgenera were found, all were recovered as monophyletic taxa with the sole exception of Dendroskusea stat. nov. Fifteen additional genera, three of which are new, and 12 additional subgenera, 11 of which are new, are proposed for monophyletic clades, and a few lineages represented by a single species, based on tree topology, the principle of equivalent rank, branch support and the number and nature of the characters that support the branches. Acartomyia stat. nov. , Aedimorphus stat. nov. , Cancraedes stat. nov. , Cornetius stat. nov. , Geoskusea stat. nov. , Levua stat. nov. , Lewnielsenius stat. nov. , Rhinoskusea stat. nov. and Sallumia stat. nov., which were previously recognized as subgenera of various genera, are elevated to generic status. Catageiomyia stat. nov. and Polyleptiomyia stat. nov. are resurrected from synonymy with Aedimorphus, and Catatassomyia stat. nov. and Dendroskusea stat. nov. are resurrected from synonymy with Diceromyia. Bifidistylus gen. nov. (type species: Aedes lamborni Edwards) and Elpeytonius gen. nov. (type species: Ochlerotatus apicoannulatus Edwards) are described as new for species previously included in Aedes (Aedimorphus), and Petermattinglyius gen. nov. (type species: Aedes iyengari Edwards) and Pe. (Aglaonotus) subgen. nov. (type species: Aedes whartoni Mattingly) are described as new for species previously included in Aedes (Diceromyia). Four additional subgenera are recognized for species of Ochlerotatus, including Oc. (Culicada) stat. nov. (type species: Culex canadensis Theobald), Oc. (Juppius) subgen. nov. (type species: Grabhamia caballa Theobald), Oc. (Lepidokeneon) subgen. nov. (type species: Aedes spilotus Marks) and Oc. (Woodius) subgen. nov. (type species: Aedes intrudens Dyar), and seven are proposed for species of Stegomyia: St. (Actinothrix) subgen. nov. (type species: Stegomyia edwardsi Barraud), St. (Bohartius) subgen. nov. (type species: Aedes pandani Stone), St. (Heteraspidion) subgen. nov. (type species: Stegomyia annandalei Theobald), St. (Huangmyia) subgen. nov. (type species: Stegomyia mediopunctata Theobald), St. (Mukwaya) subgen. nov. (type species: Stegomyia simpsoni Theobald), St. (Xyele) subgen. nov. (type species: Stegomyia desmotes Giles) and St. (Zoromorphus) subgen. nov. (type species: Aedes futunae Belkin). Due to the unavailability of specimens for study, many species of Stegomyia are without subgeneric placement. As is usual with generic‐level groups of Aedini, the newly recognized genera and subgenera are polythetic taxa that are diagnosed by unique combinations of characters. The analysis corroborates the previous observation that ‘Oc. (Protomacleaya)’ is a polyphyletic assemblage of species.  相似文献   

8.
9.
Abstract Two new genera and eight new species of featherwing beetles (Coleoptera: Ptiliidae) possessing a remarkable horizontal perforation of the mesoventral keel are described: Skidmorella vietnamensis sp.n. (Vietnam), S. memorabilis sp.n. (Indonesia), S. serrata sp.n. (Vietnam), Fenestellidium capensis gen. et sp.n. (South Africa, type species), F. kakamegaensis sp.n. (Kenya), Cissidium okuensis sp.n. (Cameroon), Dacrysoma usambarensis gen. et sp.n. (Tanzania, type species) and D. felis sp.n. (Madagascar). A phylogenetic analysis of 24 taxa and 37 parsimony‐informative characters supports the hypothesis of a single origin of the mesoventral perforation, thus uniting Discheramocephalus, Skidmorella, Africoptilium, Fenestellidium, Cissidium and Dacrysoma into a pantropically distributed clade, for which a new tribe Discheramocephalini (type genus Discheramocephalus) is proposed. Identification keys to Discheramocephalini genera and, in some cases, to species are provided. Each new species is illustrated with scanning electron microscopy images.  相似文献   

10.
The distinctive spores produced byLophosoria, an extant monotypic fern, are examined ultrastructurally and correlated with the sporoderm of fossilCyatheacidites. The morphological and ultrastructural similarity of the two taxa provide additional information that can be used to trace the evolutionary history of this spore type.  相似文献   

11.
Summary Pseudographiella with the type species,P. variaseptata, andPhragmographium with the type species,P. ulmi, are described as new synnematous taxa. Both of these new species produce phragmospores. In addition, a new species ofDendrostilbella, D. bonari, is described as new.  相似文献   

12.
Mediterranean‐type streams are characterized by great seasonal and annual variation in flow. We studied the biology of the freshwater mussel Unio tumidiformis in such a stream, the Vascão River in southern Portugal, during a period of great interannual variation in hydrology. We studied growth patterns of the mussels between 2002–2008, and the reproductive cycle between 2005–2006. Life‐history parameters were calculated and related to environmental variables and fish community patterns. Mark–recapture growth data confirmed that observed annuli were formed annually and are therefore reliable for use in growth studies of U. tumidiformis. The von Bertalanffy growth constant K and the asymptotic length L were negatively correlated. K varied between 0.20 and 0.58 and was positively correlated with factors related to eutrophication. The maximum observed age was 7 years, and the maximum observed length was 52 mm. There was no apparent sexual dimorphism, and sexual maturity was reached at the age of 2 years. Fecundity was low, between 1500–15000 glochidia per female, and positively correlated with body length. Only one annual gametogenic cycle was identified, leading to a short‐term reproductive period in spring (tachyticity). The reproductive cycle was similar in the two years sampled, between which hydrology and water quality differed greatly. The presence of glochidia was synchronized with the period when the proportion of fish hosts (genus Squalius) was higher in the fish community. Unio tumidiformis seems to be well adapted to the natural variability in flow in temporary Mediterranean‐type streams. Modifications of the natural flow regime caused by climate change or increased water exploitation may lead to rapid declines in mussel populations.  相似文献   

13.
14.
In recent years, advances in our understanding of feline relationships have cast light on their evolutionary history. In contrast, there have been no phylogenetic analyses on machairodont felids, making it difficult to develop an evolutionary hypothesis based on the recent surge of studies on their craniomandibular morphology and functional anatomy. In this paper, I provide the first phylogenetic hypothesis of machairodont relationships based on 50 craniomandibular and dental characters from a wide range of sabercats spanning more 11 Myr. Exact searches produced 19 most‐parsimonious trees, and a strict consensus was well resolved. The Machairodontinae comprise a number of basal taxa (Promegantereon, Machairodus, Nimravides, Dinofelis, Metailurus) and a well‐supported clade of primarily Plio‐Pleistocene taxa (Megantereon, Smilodon, Amphimachairodus, Homotherium, Xenosmilus) for which the name Eumachairodontia taxon novum is proposed. Previous phenetic grouping of machairodont taxa into three distinct groups, the Smilodontini, Homotherini and Metailurini, was not supported by cladistic parsimony analysis, and forcing monophyly of these groups was significantly incompatible with character distribution. Machairodonts as a clade are not characterized by saberteeth, i.e. hypertrophied, blade‐like upper canines, but by small lower canines, as well as small M1; and large P3 parastyle. True saberteeth arose later and are a synapomorphy of the Eumachairodontia.  相似文献   

15.
Aim The larval stages of marine taxa are often assumed to have an overriding influence on the phylogeographical structure of a species as well as on rates of speciation. Phylogeographical disjunctions in high‐dispersal marine taxa are generally attributed to historical events or contemporary ecological factors. The lack of genetic structure in low‐dispersal marine taxa is often ascribed to rafting by juveniles, yet few studies discuss the effects of historical conditions. Around peninsular Florida, there are three species of the crown conch, Melongena, which have direct‐developing, crawl‐away larvae. One of these species, M. corona, is subdivided into three subspecies. We refer to these five taxa as the corona complex. We assessed the validity of these taxa and tested for patterns of phylogeographical subdivision. Location Intertidal Florida and eastern Alabama, USA, Mexico and Panama. Methods The mitochondrial DNA cytochrome c oxidase subunit I, and ribosomal DNA 16S genes were sequenced from adult individuals representing all extant taxa of Melongena. Phylogenetic trees were constructed under maximum likelihood analysis (heuristic search with tree bisection–reconnection branch‐swapping) using the program paup *. Results Sequence variability in the complex was low and suggested no systematic or phylogeographical partitioning in the corona complex. The species complex probably consists of a single lineage exhibiting no clear pattern of genetic partitioning over the entire range. Main conclusions The present study supports the designation of only four extant species within the genus: M. corona, M. patula, M. melongena and M. bispinosa. The subspecies M. corona corona, M. c. johnstonei and M. c. altispira, and the species M. sprucecreekensis and M. bicolor, should all be considered to be M. corona. Surprisingly, even with very low larval and adult vagility, no population subdivisions were noted in our genetic analyses. Our analyses also substantiate the paraphyletic status of the family Melongenidae.  相似文献   

16.
Primate shoulder morphology has been linked with locomotor habits, oftentimes irrespective of phylogenetic heritage. Among hominoids, juvenile African apes are known to climb more frequently than adults, while orangutans and gibbons maintain an arboreal lifestyle throughout ontogeny. This study examined if these ontogenetic locomotor differences carry a morphological signal, which should be evident in the scapulae of chimpanzees and gorillas but absent in taxa that do not display ontogenetic behavioral shifts. The scapular morphology of five hominoid primates and one catarrhine outgroup was examined throughout ontogeny to evaluate if scapular traits linked with arboreal activities are modified in response to ontogenetic behavioral shifts away from climbing. Specifically, the following questions were addressed: 1) which scapular characteristics distinguish taxa with different locomotor habits; and 2) do these traits show associated changes during development in taxa known to modify their behavioral patterns? Several traits characterized suspensory taxa from nonsuspensory forms, such as cranially oriented glenohumeral joints, obliquely oriented scapular spines, relatively narrow infraspinous fossae, and inferolaterally expanded subscapularis fossae. The relative shape of the dorsal scapular fossae changed in Pan, Gorilla, and also Macaca in line with predictions based on reported ontogenetic changes in locomotor behavior. These morphological changes were mostly distinct from those seen in Pongo, Hylobates, and Homo and imply a unique developmental pattern, possibly related to ontogenetic locomotor shifts. Accordingly, features that sorted taxa by locomotor habits and changed in concert with ontogenetic behavioral patterns should be particularly useful for reconstructing the locomotor habits of fossil forms. Am J Phys Anthropol 152:239–260, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

17.
18.
A total of 62 species, representing 24 of the 28 supraspecific taxa of skates, was surveyed for the presence, distribution, and structure of alar and malar thorns. The survey revealed that alar thorns are almost universally present in mature male skates, and that malar thorns are of two types that may have separate origins. The location and orientation of alar thorns differed in two major clades of skates (groups I and II). They were either exposed on the disc with the crown oriented obliquely to the long axis of the base or imbedded in slits in the integument and oriented parallel to the long axis of the base. Group I possessed the former type of thorns and, with several exceptions, group II possessed the latter type. Group I either lacked malar thorns or possessed malar thorns that were most likely derived from generalized placoid scales. Group II possessed, with several exceptions, malar thorns derived from enlarged placoid scales. Within group I the supraspecific taxa Atlantoraja and Rioraja possessed unique alar thorns that were reclined laterally and associated with lateral grooves in the integument. Within group II the supraspecific taxa Anacanthobatis, Cruriraja, Dipturus, Okamejei, Raja, the North Pacific Assemblage, and the Amphi-American Assemblage had a large barb on the distal section of the crown of the alar thorn that suggests that these taxa form a clade. The crown of the alar thorns of the latter five supraspecific taxa was undulatory, thus supporting their monophyletic status. Another assemblage within group II had ridges that ran most of the length of the crown of the alar thorns corroborating their monophyletic status. The survey also suggested that variation of integumentary grooves associated with the alar thorns in Bathyraja, and presence or absence of malar thorns in Psammobatis, may be phylogenetically informative. © 1996 Wiley-Liss, Inc.  相似文献   

19.
Most species of freshwater mussels (Unionoida) show a wide variability in shell form and size but an understanding of which factors determine unionoid morphology is poor. We identified ecophenotypic trends in shell and internal characters within three unionoid species from two habitat types (marinas and river) of the River Thames, UK, using traditional and modern morphometric techniques. In marinas, all species grew to larger maximum sizes than in the river, which might be a result of higher temperatures and phytoplankton densities in marinas. Unio pictorum in marinas was more elongated than in the river and Fourier shape analysis revealed a trend from dorsally arched river specimens to straight dorsal and pointed posterior margins in marina individuals. The degree of shell elongation and shape of dorso‐posterior margin were not associated with sediment composition, but were associated with the different hydrological characters of the two habitat types. Relative shell width was a poor indicator of collection site and influenced by allometric growth. Unlike U. pictorum, a difference in shell elongation of marina and river mussels could not be detected in Unio tumidus and Anodonta anatina. However, all three species showed the same trends regarding the shape of the dorso‐posterior shell margin. This shell character may thus have broad ecological significance and could have considerable utility to palaeontologists, taxonomists, and conservation biologists. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 814–825.  相似文献   

20.
We review the evolution of dental zalambdodonty across therian mammals. Among zalambdodonts, there is little or no occlusion between the protocone and talonid basin and one of the central cusps of the upper molars (metacone or paracone) and the talonid basin of the lower molars are lost or reduced. Over two dozen genera of therian mammals show zalambdodont molars, including tenrecids, chrysochlorids, Solenodon, the marsupial mole Notoryctes, the extinct placentals Apternodus, Oligoryctes, Parapternodus, and Koniaryctes, and the extinct marsupials Necrolestes and Yalkaparidon. The chiropteran Harpiocephalus is nearly zalambdodont. Transformation series provided by paleontological or ontogenetic data, plus occlusal relationships, can be used to determine the homology of molar cusps in zalambdodont taxa. Zalambdodont dental specialization does not appear to have led to ecological specialization. With the important exception of golden moles and tenrecs, dentally zalambdodont taxa are less speciose than their nonzalambdodont sister taxa.  相似文献   

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