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1.
Five cruises to the Faroe Bank in the northeast Atlantic revealed a rich loriciferan fauna inhabiting shell gravel to fine carbonate sand. This paper describes two new species of Pliciloricus found at depths of 120-260 m. Currently, only six species of this genus have been described from various localities around the world, but several new species are currently being described. The diagnosis of the genus Pliciloricus is emended to include the two new taxa. The first of the two new species Pliciloricus leocaudatus sp. n. is characterized by having four new kinds of scalids in the second row and an additional row of alternating plates in the eighth row. The second species Pliciloricus shukeri sp. n. is characterized in having a secondary double organ in the third row. The morphology of the two species, including the new structures, has been investigated using LM and scanning electron microscopy. Conclusively, the scalid pattern of the introvert of Pliciloricus has been re-evaluated, due to the finding of the new structures. Additionally, a discussion of the life cycle of the genus Pliciloricus is given, since the postlarval stage is reduced in both new species. 相似文献
2.
《Lichenologist (London, England)》2001,33(1):47-62
Abstract:Three species of the Buellia epigaea -group, Buellia dijiana Trinkaus,Buellia georgei Trinkaus, Mayrhofer & Elix, and Buellia lobata Trinkaus & Elix, are described as new from Australia. The taxonomy, morphology, anatomy, chemistry, biogeography, and ecology of the three taxa are discussed. Characters which distinguish these species from the corresponding taxa in the northern hemisphere include secondary compounds (presence of xanthones) and filiform conidia. An extended key is provided for the whole Buellia epigaea group as well as other terricolous species of the genus. 相似文献
3.
Seyed Akbar Khodaparast Susumu Takamatsu Mamoru Harada Mehrdad Abbasi Sahar Samadi 《Mycological Progress》2012,11(3):741-752
Taxonomy of the genus Leveillula has long been considered as a challenge in powdery mildew systematics. The rDNA diversity has recently been used for phylogenetic analysis of several specimens of the genus Leveillula. In the present study, additional rDNA ITS sequences are provided and a new phylogenetic analysis is carried out aiming at a better understanding of the genetic diversity in the genus Leveillula. New analyses confirmed that L. taurica is unique in the genus, as it exhibits an intraspecific gene sequence diversity considerably higher than in other species. In several cases L. taurica s. lat. on a certain host plant species has a sequence different from L. taurica on other host plants. Moreover, DNA data indicated different lineages among L. taurica specimens which were hardly distinguishable by morphology. More than one genotype occurring on a single host is sometimes possible. According to these results, several races such as Leveillula on Artemisia, Acroptilon, Onobrychis, are molecularly well characterized. While there is enough molecular evidence to delimit such races as independent taxa, clear morphological delimitations between these new and already published taxa are very difficult or even impossible. However, ecological features, and above all, host specificity for biotrophic fungi such as powdery mildew, would be a good criterion to discriminate cryptic taxa along with rDNA sequences. In fact, many collections of Leveillula strains on different hosts show their own type of conidial morphology, which is usually consistent for a strain on a single host species. Hence, we have proposed to describe new species for Leveillula on some host plants such as Artemisia, Acroptilon, Echinops and Onobrychis. 相似文献
4.
W. R. Nickle 《Journal of nematology》1972,4(2):113-146
The genera of the insect parasitic nematode family Mermithidae axe reviewed, and 16 of them axe redescribed and illustrated. Information is given on methods of rearing adult mermithid specimens and on host specificity. The four types of merrnithid life cycles axe described in detail. One figure shows the variety of insects parasitized by merrnithids and the location and size of the nematode within the insect. Several mermithid eggs are illustrated, and their usefulness in identification is discussed.Taxonomically, the primary emphasis is on the adult stages of the merrnithJds with larval and egg characteristics supplementaxy. An emended family diagnosis is given. Merrnis subnigrescens is considered a synonym of M. nigrescens, and M. tahitiensis is synonymized with M. mirabilis. Hydromermis contorta is accepted, leaving the genus Paramermis in an uncertain position. Study of the Steiner collections of Limnornermis bathybia indicates that Limnornerrnis is accepted as a valid genus. The adults of Agamermis decaudata are descried and illustrated for the first time. The genus Gastromermis is limited to the long single-spiculed forms, as it is now apparent that five or more genera have ventrally shifted mouth orifices. Amphirnermis tinyi n. sp. is described from damselflies from Louisiana. The genus Lanceimermis is accepted, and three species in this genus are illustrated. The taxon Reesimermis nielseni has been accepted for this important parasite of more than 20 mosquito species. This nematode previously has been referred to as Romanomermis sp. Romanomermis iyengari is transferred to the genus Reesirnermis. Diximermis peterseni n. gen., n. sp., from anopheline mosquitoes, is described and iUustrated. The adults of Agamomermis culicis which parasitize Aedes sollicitans, are described for the first time, and the species placed in a new genus, Perutilimermis. The new genus Neornesornermis is proposed for Mesomermis flumenalis Welch, 1962. Several problems on mermithid morphology and taxonomy are discussed. Type material is established for some of the taxa. 相似文献
5.
《Lichenologist (London, England)》1998,30(6):551-562
The new species,Polysporina terricolaKantvilas from south-eastern Tasmania, is described and compared to other species in the genus. It is well-characterized by a range of morphological, anatomical and ecological characters, especially by the presence of oil paraphyses and oil droplets in the hymenium, features unknown in other members of the genus. Species ofPolysporinaare best separated by the following characters: size and morphology of the apothecia, size of ascospores, thickness of paraphyses and height of the hymenium. The combinationsP. ferruginea(Lettau) M. Steiner andP. pusilla(Anzi) M. Steiner are validated. A key to the taxa studied is provided. 相似文献
6.
Knud Andreas J?nsson Martin Irestedt Les Christidis Sonya M. Clegg Ben G. Holt Jon Fjelds? 《Proceedings. Biological sciences / The Royal Society》2014,281(1777)
Many insular taxa possess extraordinary abilities to disperse but may differ in their abilities to diversify and compete. While some taxa are widespread across archipelagos, others have disjunct (relictual) populations. These types of taxa, exemplified in the literature by selections of unrelated taxa, have been interpreted as representing a continuum of expansions and contractions (i.e. taxon cycles). Here, we use molecular data of 35 out of 40 species of the avian genus Pachycephala (including 54 out of 66 taxa in Pachycephala pectoralis (sensu lato), to assess the spatio-temporal evolution of the group. We also include data on species distributions, morphology, habitat and elevational ranges to test a number of predictions associated with the taxon-cycle hypothesis. We demonstrate that relictual species persist on the largest and highest islands across the Indo-Pacific, whereas recent archipelago expansions resulted in colonization of all islands in a region. For co-occurring island taxa, the earliest colonists generally inhabit the interior and highest parts of an island, with little spatial overlap with later colonists. Collectively, our data support the idea that taxa continuously pass through phases of expansions and contractions (i.e. taxon cycles). 相似文献
7.
Steven D. Johnson Craig I. Peter Allan G. Ellis Elin Boberg Christo Botes Timothe��s van der Niet 《Plant Systematics and Evolution》2011,292(1-2):95-103
The large terrestrial orchid genus Satyrium underwent evolutionary radiations in the Cape floral region and the grasslands of southern and eastern Africa. These radiations were accompanied by tremendous diversification of the unusual twin-spurred flowers that characterize the genus, but pollination data required to interpret these patterns of floral evolution have been lacking for grassland species in the genus. Here we document pollinators, nectar properties, and levels of pollination success for 11 grassland Satyrium species in southern and south-central Africa. Pollinators of these species include bees, beetles, butterflies, hawkmoths, noctuid moths, long-proboscid flies, and sunbirds. Most species appear to be specialized for pollination by one functional pollinator group. Long-proboscid fly pollination systems are reported for the first time in Satyrium (in S. macrophyllum and a high-altitude form of S. neglectum). Floral morphology, especially spur length and rostellum structure, differs markedly among plants with different pollinators, while nectar volume, concentration, and sugar composition are fairly uniform across species. Most taxa exhibited high levels of pollination success (>50% of flowers pollinated), a trend that can be attributed to the presence of nectar in the twin spurs. 相似文献
8.
Donald H. Pfister Carlo Agnello Angela Lantieri Katherine F. LoBuglio 《Mycological Progress》2013,12(4):667-674
The family Caloscyphaceae with a single genus, Caloscypha, has been considered to include a single species, C. fulgens. Study of an overlooked second species, Caloscypha incarnata from North Africa and Italy, using SSU, LSU rDNA, and morphology allows placement of this species in a new genus, Kallistoskypha, in the Caloscyphaceae. This fungus is found in association with Eucalyptus species. The species was recently redescribed from Spain under the name Marcelleina parvispora. Caloscypha fulgens, the type species of the genus Caloscypha, shows sequence variation from across its range. 相似文献
9.
Melanophryniscus is a genus of small toads inhabiting the southern portion of South America. This genus is considered basal within the family Bufonidae. Data on larval chondrocranial morphology do not exist for the genus and larval internal oral anatomy has only been described for a single species. Here, we describe chondrocranial and internal oral morphology in Melanophryniscus montevidensis , M. orejasmirandai and M. sanmartini . Chondrocranial morphology is similar among the species examined. Comparisons with other bufonids and with outgroup taxa suggest that the following chondrocranial characters may represent synapomorphies for the Bufonidae: free (or absent) ceratobranchial IV, a reduced or absent larval crista parotica, the lack of a larval otic process, and late development of thin, poorly chondrified orbital cartilages. The presence of an elongated processus anterior dorsalis of the suprarostral alae and the absence of a chondrified commissura quadratoorbitalis appear to be unique in Melanophryniscus among bufonids. Internal oral anatomy is conserved in Melanophryniscus , and among bufonids in general. 相似文献
10.
Nana Gratiashvili Abel Bernadou Masaki Suefuji Bernhard Seifert Jürgen Heinze 《Organisms Diversity & Evolution》2014,14(3):259-267
A small minority of the presently recognized ~12,500 species of ants are slave-makers, which permanently depend on the help of “slave workers,” that is workers of other ant species, which they pillage as brood from their nests in well-organized slave raids. The genus Myrmoxenus is one of the most species-rich taxa of slave-making ants, but individual species are often not well-delimited. Here, we compare behavior, morphometry, and nuclear and mtDNA sequences between two taxa of Myrmoxenus: Myrmoxenus tamarae (Arnoldi, 1968), known only from its type locality in Georgia, and the wide-spread M. ravouxi (André, 1896) to determine if the former might simply represent a Caucasian variant of the latter. Workers of the two taxa differed clearly in locomotor activity and slightly also in morphometry, while genetic investigations with nuclear and mitochondrial genes revealed only a weak differentiation. Given that Myrmoxenus appears to be a genus with a relatively recent radiation, we suggest to conservatively keep the present taxonomic situation with M. ravouxi and M. tamarae as separate species. The latter would then include specimens from Eastern Turkey and probably also Ukraine. Further studies, in particular in Greece and Turkey, might help to clarify the status of these endangered ants. 相似文献
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12.
《L'Anthropologie》2022,126(4):103055
Almost three-quarters of a century ago, Ernst Mayr (1950) shocked paleoanthropologists into an exceptionalist taxonomic minimalism that lingers today. As a result, a constant stream of new fossil discoveries has been shoehorned wherever possible into existing taxa, almost irrespective of morphology. This compression has been especially true at the level of the genus, where virtually all except very early hominins have over the last couple of decades been classified and named according to the unconscious algorithm, “if it isn’t Australopithecus, it is Homo” (and vice versa). This has led to a vastly overstuffed genus Homo, which has lost any phylogenetic or morphological coherence. Genera are monophyletic clusters of species; and although their boundaries in terms of species content are arbitrary, they do contain phylogenetic structure that ultimately needs to be expressed. Homininae is a large and diverse taxon; and this essay is a plea to paleoanthropologists not only to reflect the phylogenetic structure within it by employing an adequate number of generic and species names, but at the same time to acknowledge the internationally agreed rules (especially of priority) that govern the naming of zoological taxa. 相似文献
13.
Paulo José Fernandes Guimarães Marcus Felippe Oliveira da Silva Maria José Reis da Rocha 《Brittonia》2017,69(2):231-240
Acisanthera is a genus of annual or perennial herbs or subshrubs that inhabit seasonal environments of the Neotropics. It is divided into four sections which include 22 accepted species and 17 varieties. Here, the nomenclatural history of the genus is reviewed since a species name was not assigned to the genus when it was first described. The collection of Patrick Browne later received three replacement names, which has generated different interpretations. The type collection and currently accepted names for all taxa of Acisanthera are provided. 相似文献
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15.
Morphological revision of Fulvifomes robiniae, as well as phylogenetic inferences based on nITS and nLSU markers, indicated that the species has a narrower concept in its morphology and distribution. Other morphologically related taxa arise from this taxonomic approach. Fulvifomes cedrelae is not accepted as a synonym of F. robiniae, and Fulvifomes squamosus sp. nov. is described as new based on Peruvian specimens. Based on morphology, phylogenetic relationships and host distributions, the taxonomic implication for the genus and other related taxa are discussed. 相似文献
16.
《Mycological Research》2006,110(6):646-656
Bremia graminicola (Chromista, Peronosporales) is a common downy mildew pathogen of Arthraxon spp. (Poaceae) in Central to East Asia and the only species of Bremia parasitic on grasses. Despite its widespread occurrence and apparent differences in host range and morphology compared with other species of the genus, its placement in Bremia has not been challenged for the past 90 y. Its current taxonomic position is revised based on sporangiophore morphology and ultrastructure, haustorium morphology, and nu-rDNA sequence analysis. Haustorium morphology and sporangiophore ultrastructure indicate that B. graminicola is not a member of the genus Bremia, which shows affinities to Plasmopara and Paraperonospora. Based on haustorium morphology, B. graminicola appears to be more closely related to Viennotia oplismeni, although the sporangiophore morphology is strikingly different between these two taxa. This is supported by molecular analyses based on a near-representative sample of nuLSU rDNA sequences of downy mildew genera, whereby B. graminicola is revealed as the sister taxon of V. oplismeni with 100 % BS support under all phylogenetic optimality criteria applied. Relationships of this clade to other groups are less clear. However, network and reduced-consensus analyses show that this lack of resolution is mainly due to the ambiguous molecular affinities of Sclerospora graminicola. Omitting this highly divergent taxon results in considerable support for a clade comprised of taxa with globose to pyriform haustoria, including B. lactucae, and for the sister-group relationship of B. graminicola and V. oplismeni with Hyaloperonospora. Consequently, a new genus, Graminivora, is described to accommodate B. graminicola. 相似文献
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18.
Gary C. Williams 《ZooKeys》2013,(283):15-42
A taxonomic assessment of four species of octocorals from the northeastern Pacific Ocean (British Columbia to California) is provided. Included here are a new species of clavulariid stolonifieran Cryptophyton, a new species of the nephtheid soft coral Gersemia, an undetermined species of soft coral in the genus Alcyonium that has been referred in the literature by several other names, and a new genus is named for a plexaurid sea fan originally described in the Indo-Pacific genus Euplexaura. Discussions are included that compare the species to related taxa, or provide revisionary assessments. 相似文献
19.
《Journal of Asia》2021,24(4):1301-1312
The hoverfly genus Merodon Meigen, 1803 (Diptera, Syrphidae), which comprises more than 200 species is distributed in the Palaearctic and Afrotropical Region, but one species, Merodon equestris, is a pest of flower bulbs and has been invasive into New Zealand and North America. In this work, the Merodon aurifer species group, a member of the M. avidus-nigritarsis lineage, is revised. The diagnostic characters of the M. aurifer species group, and the morphological differences between M. aurifer Loew, 1862 and M. nudicorpus sp. n. are explained and illustrated, as well as their distribution map. A detailed study of the type material resulted in three new synonyms: M. distinctus Palma, 1863 is a junior synonym of M. aurifer; M. manicatus (Sack, 1938) and M. testacoides Hurkmans, 1993 are junior synonyms of M. testaceus.Lectotypes are designated for two taxa M. aurifer and M. manicatus instead of the erroneously designated types for these species in Hurkmans (1993). 相似文献
20.
《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1997,320(8):615-620
The abaxial and adaxial epidermis of young and mature leaves of the South American species of Chenopodium L. (Chenopodiaceae) have mucilage secreting glandular structures that have not been reported in previous studies, either for the Chenopodiaceae or other Phanerogamic taxa. Their morphology and function have been studied and all stages of their ontogenic pathway have been described and illustrated. The name ‘glandular mucilagene surface’ is proposed. Their adaptative value is discussed and differences from other leaf epidermal differentiations are noted. These structures have been discovered in Chenopodium species living in Patagonia, their presence in all South American species — native and exotic ones — of the genus has been investigated and proved. The possibility that it could be a generic feature is suggested. 相似文献