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1.
Vasseuromys is a species‐rich genus of small‐ to medium‐sized glirids spanning the latest Oligocene to late Miocene of Europe and western Asia. Despite extensive discoveries over the past 50 years, little phylogenetic work has been done on Vasseuromys. This study presents the first phylogenetic analysis of the genus that includes all the described species and a new taxon Vasseuromys tectus sp. nov. from the late Miocene of eastern Europe, providing the first insights into the evolutionary relationships within the clade. Results suggest that the genus is clearly paraphyletic. Two strongly supported genus‐level clades are recognized within ‘Vasseuromys’: a restricted Vasseuromys clade (containing the three species, V. pannonicus, V. rugosus and V. tectus) and the Glirulus clade that includes ‘Vasseuromysduplex. The remaining ‘Vasseuromys’ species are found to constitute a set of paraphyletic taxa, with the polyphyletic ‘Ramys’ nested within it. The genus Gliruloides is synonymized with Glirulus. Vasseuromys tectus sp. nov. is the most derived member of the genus in having a greater number of cheek teeth ridges including constantly present anterotrope, centrotrope, second prototrope on M1–2, third metatrope on M2, two to three posterotropids on p4 and strong ectolophids on lower molars. The results of the study confirm a European origin for Vasseuromys while suggesting that the late Miocene species of the genus dispersed from the east in the early Turolian.  相似文献   

2.
The diatom genus Chaetoceros is one of the most abundant and diverse phytoplankton in marine and brackish waters worldwide. Within this genus, Chaetoceros socialis has been cited as one of the most common species. However, recent studies from different geographic areas have shown the presence of pseudo‐cryptic diversity within the C. socialis complex. Members of this complex are characterized by curved chains (primary colonies) aggregating into globular clusters, where one of the four setae of each cell curves toward the center of the cluster and the other three orient outwards. New light and electron microscopy observations as well as molecular data on marine planktonic diatoms from the coastal waters off Chile revealed the presence of two new species, Chaetoceros sporotruncatus sp. nov. and C. dichatoensis. sp. nov. belonging to the C. socialis complex. The two new species are similar to other members of the complex (i.e., C. socialis and C. gelidus) in the primary and secondary structure of the colony, the orientation pattern of the setae, and the valve ultrastructure. The only morphological characters that can be used to differentiate the species of this complex are aspects related to resting spore morphology. The two newly described species are closely related to each other and form a sister clade to C. gelidus in molecular phylogenies. We also provide a phylogenetic status along with the morphological characterization of C. radicans and C. cintus, which are genetically related to the C. socialis complex.  相似文献   

3.
A multigene phylogeny using COI‐5P (mitochondrial cytochrome c oxidase subunit 1), psbA (PSII reaction center protein D1), and EF2 (elongation factor 2) sequence data for members of the tribe Corallineae was constructed to assess generic boundaries. We determined that traditional reliance on conceptacle position as an indicator of generic affinities in the Corallineae is not supported and taxonomic changes are required. We found that species currently assigned to Pseudolithophyllum muricatum resolved within the Corallineae in all analyses. This is the first record of crustose members in the subfamily Corallinoideae. Further‐more, the genus Serraticardia was polyphyletic; we propose to synonomize Serraticardia with Corallina, transfer the type species Smaxima to Corallina (Cmaxima (Yendo) comb. nov.), and describe the new genus Johansenia for Smacmillanii (Jmacmillanii (Yendo) comb. nov.). Our molecular data also indicate that species in the genus Marginisporum have evolutionary affinities among species of Corallina and these genera should also be synonymized. This necessitates the combinations Caberrans (Yendo) comb. nov. for Maberrans (Yendo) Johansen & Chihara, Ccrassissima (Yendo) comb. nov. for M. crassissimum (Yendo) Ganesan, and C. declinata (Yendo) comb. nov. for M. declinata (Yendo) Ganesan. Corallina elongata was divergent from all other members of Corallina and is transferred to a new genus, Ellisolandia (E. elongata (J. Ellis & Solander) comb. nov). In addition, COI‐5P and internal transcribed spacer (ITS) data combined with morphological characters were used to establish that rather than the four Corallina species recognized in Canada, there are nine.  相似文献   

4.
The diversity of the bladed species of the red algal order Bangiales from the Iberian Mediterranean shores has been reassessed after a detailed study of this region. Prior to this study, 11 bladed species of Bangiales had been reported from Mediterranean waters: Porphyra atropurpurea, P. cordata, P. coriacea, P. dioica, P. linearis, P. purpurea, P. umbilicalis, Pyropia leucosticta, Pyropia koreana (as P. olivii), Py. elongata (as P. rosengurttii) and Py. suborbiculata. A combined analysis of the nuclear nSSU and the plastid rbcL genes together with detailed morphological studies has confirmed the presence of species within the genera Porphyra and Pyropia and also revealed a third, undescribed genus, Themis gen. nov. Porphyra linearis, Pyropia elongata and the introduced Pyropia koreana had been previously listed for the Mediterranean and were recorded in this study. An additional four species, including the introduced Pyropia suborbiculata and three new species: Pyropia parva sp. nov., Themis ballesterosii sp. nov., and Themis iberica sp. nov. were also observed. Hence, most of the Porphyra species traditionally reported along these shores were not reported in this survey. This new floristic Bangiales composition confirms the importance of the Mediterranean basin as a hotspot for biodiversity, possible endemics of ancient origin and high proportion of introductions. Our data also continue to confirm the extent of Bangiales diversity at regional and worldwide levels.  相似文献   

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8.
The current study focuses on four species from the primarily marine diatom genus Craspedostauros that were observed growing attached to numerous sea turtles and sea turtle‐associated barnacles from Croatia and South Africa. Three of the examined taxa, C. danayanus sp. nov., C. legouvelloanus sp. nov., and C. macewanii sp. nov., are described based on morphological and, whenever possible, molecular characteristics. The new taxa exhibit characters not previously observed in other members of the genus, such as the presence of more than two rows of cribrate areolae on the girdle bands, shallow perforated septa, and a complete reduction of the stauros. The fourth species, C. alatus, itself recently described from museum sea turtle specimens, is reported for the first time from loggerhead sea turtles rescued in Europe. A 3‐gene phylogenetic analysis including DNA sequence data for three sea turtle‐associated Craspedostauros species and other marine and epizoic diatom taxa indicated that Craspedostauros is monophyletic and sister to Achnanthes. This study, being based on a large number of samples and animal specimens analyzed and using different preservation and processing methods, provides new insights into the ecology and biogeography of the genus and sheds light on the level of intimacy and permanency in the host–epibiont interaction within the epizoic Craspedostauros species.  相似文献   

9.
The genus Balechina (=subgenus Pachydinium) was established for heterotrophic gymnodinioid dinoflagellates with a thick cell covering. The type species, B. pachydermata (=Gymnodinium pachyderm‐atum), showed numerous fine longitudinal striae, whereas B. coerulea (=G. coeruleum) showed ~24 prominent longitudinal surface ridges or furrows and a distinctive blue pigmentation. We have investigated the morphology and molecular phylogeny of these taxa and the species Gymnodinium cucumis, G. lira and G. amphora from the western Mediterranean, Brazil and Japan. Sudden contractions at the cingulum level were seen in B. pachydermata, which also showed a high morphological variability which included morphotypes that have been described as Amphidinium vasculum, G. amphora, G. dogielii and G. gracile sensu Kofoid and Swezy. Molecular phylogeny based on small subunit rRNA gene sequences revealed that Balechina coerulea, G. cucumis and G. lira formed a clade distantly related to the clade of the type species, B. pachydermata, and G. amphora. We propose the new genus Cucumeridinium for the species with longitudinal ridges and a circular apical groove (Cucumeridinium coeruleum comb. nov., C. lira comb. nov. and C. cucumis comb. nov.), and Gymnodinium canus and G. costatum are considered synonyms of C. coeruleum. The genus Balechina remains for the species with a double‐layer cell covering, bossed surface with fine striae, and an elongated elliptical apical groove. At present, the genus is monotypic containing only B. pachydermata.  相似文献   

10.
Proctonotidae and Madrellidae are families that belong to the suborder Cladobranchia. Historically, both have been the subjects of taxonomic confusion. Thus, Proctonotidae Gray, 1853, was subsequently named as Zephyrinidae Iredale and O'Donoghue, 1923 and Janolidae Pruvot‐Fol, 1933, but currently both are considered as synonyms of Proctonotidae. On the other hand, Alder and Hancock (1864) erected the genus Madrella in Proctonotidae. Here, we completed a detailed morphological and molecular study of four apparently undescribed species of Madrellidae and Proctonotidae from the Indo‐Pacific. We performed a maximum likelihood and Bayesian inference phylogenetic analyses using two mitochondrial and one nuclear genes to improve the understanding of the families. Prompted by our results, Janolidae is removed from synonymy with Proctonotidae. Within Janolidae, there are two well‐supported clades. One includes species with smooth cerata that are found in the Atlantic and eastern Pacific Oceans. The taxa in this clade include the type species of Antiopella and several other species. We resurrect Antiopella as the valid name for this clade. The sister clade to Antiopella includes a variety of taxa with species that have been traditionally included in Janolus Bergh, 1884 and Bonisa Gosliner, 1981. Further systematic revision requires more comprehensive taxon sampling. The new species discovered have clear morphological differences and strong molecular support. They include Madrella amphora Pola and Gosliner sp. nov. , Janolus tricellariodes Pola and Gosliner sp. nov. , Janolus flavoanulatus Pola and Gosliner sp. nov., and Janolus incrustans Pola and Gosliner sp. nov.  相似文献   

11.
The complete life cycle and developmental stages of the fluke, Metorchis ussuriensis sp. nov. (Trematoda, Platyhelminthes), are herein described. The results of the present experiments showed that, for flukes from the Primorsky Region in the Russian southern Far East, the first intermediate hosts are the snails Parafossarulus spiridonovi and Boreoelona ussuriensis, and the second intermediate hosts are freshwater fish, tadpoles, and snails. The definitive host in this experiment was Anas platyrhynchos dom. Morphometric parameters of M. ussuriensis sp. nov. demonstrate similarities with Metorchis taiwanensis, but the two species differ in the sizes of their bodies, sizes of suckers of adult worms, and sizes of cercariae, as well as respective positions of the finfold in cercariae. Phylogenetic reconstructions and genetic distances using the cox1 gene sequences support the conclusion that M. ussuriensis sp. nov. is well distinguished from all other species of the genus Metorchis, while sequences of internal transcribed spacers (ITS1 and ITS2) failed to separate Mussuriensis sp. nov., Metorchis bilis, and Metorchis xanthosomus. In addition, we sequenced 1,402 bp of the 28SrRNA gene of Mussuriensis sp. nov. being the first 28S sequences in the genus Metorchis. Comparison to other trematodes suggests that 28SrRNA could proof suitable for the differentiation of trematode species.  相似文献   

12.
Chlamydomonas (Cd.) is one of the largest but most polyphyletic genera of freshwater unicellular green algae. It consists of 400–600 morphological species and requires taxonomic revision. Toward reclassification, each morphologically defined classical subgenus (or subgroup) should be examined using culture strains. Chlamydomonas subg. Amphichloris is characterized by a central nucleus between two axial pyrenoids, however, the phylogenetic structure of this subgenus has yet to be examined using molecular data. Here, we examined 12 strains including six newly isolated strains, morphologically identified as Chlamydomonas subg. Amphichloris, using 18S rRNA gene phylogeny, light microscopy, and mitochondria fluorescent microscopy. Molecular phylogenetic analyses revealed three independent lineages of the subgenus, separated from the type species of Chlamydomonas, Cd. reinhardtii. These three lineages were further distinguished from each other by light and fluorescent microscopy—in particular by the morphology of the papillae, chloroplast surface, stigmata, and mitochondria—and are here assigned to three genera: Dangeardinia emend., Ixipapillifera gen. nov., and Rhysamphichloris gen. nov. Based on the molecular and morphological data, two to three species were recognized in each genus, including one new species, I. pauromitos. In addition, Cd. deasonii, which was previously assigned to subgroup “Pleiochloris,” was included in the genus Ixipapillifera as I. deasonii comb. nov.  相似文献   

13.
The symbiotic dinoflagellate Gymnoxanthella radiolariae T. Yuasa et T. Horiguchi gen. et sp. nov. isolated from polycystine radiolarians is described herein based on light, scanning and transmission electron microscopy as well as molecular phylogenetic analyses of SSU and LSU rDNA sequences. Motile cells of G. radiolariae were obtained in culture, and appeared to be unarmored. The cells were 9.1–11.4 μm long and 5.7–9.4 μm wide, and oval to elongate oval in the ventral view. They possessed an counterclockwise horseshoe‐shaped apical groove, a nuclear envelope with vesicular chambers, cingulum displacement with one cingulum width, and the nuclear fibrous connective; all of these are characteristics of Gymnodinium sensu stricto (Gymnodinium s.s.). Molecular phylogenetic analyses also indicated that G. radiolariae belongs to the clade of Gymnodinium s.s. However, in our molecular phylogenetic trees, G. radiolariae was distantly related to Gymnodinium fuscum, the type species of Gymnodinium. Based on the consistent morphological, genetic, and ecological divergence of our species with the other genera and species of Gymnodinium s.s., we considered it justified to erect a new, separate genus and species G. radiolariae gen. et sp. nov. As for the peridinioid symbiont of radiolarians, Brandtodinium has been erected as a new genus instead of Zooxanthella, but the name Zooxanthella is still valid. Brandtodinium is a junior synonym of Zooxanthella. Our results suggest that at least two dinoflagellate symbiont species, peridinioid Zooxanthella nutricula and gymnodinioid G. radiolariae, exist in radiolarians, and that they may have been mixed and reported as “Z. nutricula” since the 19th century.  相似文献   

14.
Morphological, anatomical, and molecular sequence data were used to assess the establishment and phylogenetic position of the genus Wilsonosiphonia gen. nov. Phylogenies based on rbcL and concatenated rbcL and cox1 loci support recognition of Wilsonosiphonia gen. nov., sister to Herposiphonia. Diagnostic features for Wilsonosiphonia are rhizoids located at distal ends of pericentral cells and taproot‐shaped multicellular tips of rhizoids. Wilsonosiphonia includes three species with diagnostic rbcL and cox1 sequences, Wilsonosiphonia fujiae sp. nov. (the generitype), W. howei comb. nov., and W. indica sp. nov. These three species resemble each other in external morphology, but W. fujiae is distinguished by having two tetrasporangia per segment rather than one, W. indica by having abundant and persistent trichoblasts, and W. howei by having few and deciduous trichoblasts.  相似文献   

15.
The genus Coelastrella was established by Chodat (Bull. Soc. Bot. Geneve, 13 [1922] 66), and was characterized as being unicellular or in few‐celled aggregations with many longitudinal ribs on the cell wall. Many species of this genus showed strong ability to accumulate carotenoids and oils, so they have recently attracted much attention from researchers due to its potential applicability in the energy and food industries. In this study, a total of 23 strains of Coelastrella were sampled from China, and three new species and two new varieties were described: C. thermophila sp. nov., C. yingshanensis sp. nov., C. tenuitheca sp. nov., C. thermophila var. globulina var. nov., C. rubescens var. oocystiformis var. nov. Besides 18S rDNA and ITS2 sequences, we have newly sequenced the tufA gene marker for this taxon. Phylogenetic analysis combined with morphological studies revealed four morphotypes within the Coelastrella sensu lato clade, which contained the morphotype of original Coelastrella, original Scotiellopsis, Asterarcys, and morphotype of C. vacuolata and C. tenuitheca sp. nov. The relationships between morphological differences and phylogenic diversity based on different markers were discussed. Our results support that 18S rDNA was too conserved to be used a species‐specific or even a genus‐specific marker in this clade. The topology of tufA gene‐based phylogenetic tree had a better match with the morphological findings.  相似文献   

16.
Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.  相似文献   

17.
Type material of Navicula kotschyi was studied, and this species was transferred to Dorofeyukea gen. nov. as D. kotschyi comb. nov. Dorofeyukea was described on the basis of DNA sequence and morphological data. Additional species assigned to this genus that were previously included in Navicula include: D. ancisa comb. nov., D. grimmei comb. nov., D. ivatoensis comb. nov., D. orangiana comb. nov., D. rostellata comb. nov. & stat. nov., D. savannahiana comb. nov., D. tenuipunctata comb. nov., and D. texana comb. nov. All Dorofeyukea species share the same morphological features, including having a narrow stauroid fascia surrounded by 1–3 irregularly shortened striae, uniseriate, and weakly radiate striae, circular, or rectangular puncta in the striae that are covered internally by dome‐shaped hymenes, presence of a pseudoseptum at each apex and absence of septa. Partial DNA sequences of SSU and rbcL loci show Dorofeuykae belongs to the clade of stauroneioid diatoms together with Stauroneis, Prestauroneis, Craticula, Karayevia, Madinithidium, Fistulifera, Parlibellus, and, possibly, Schizostauron. A new species from the monoraphid genus Madinithidium, M. vietnamica sp. nov., was described based on valve and chloroplast morphology as well as DNA sequence data.  相似文献   

18.
The aphid genus Blackmania gen. nov. is described. In the genus, B. eastopi sp. nov. associated with Polygonum equisetiforme (Polygonaceae) from Israel and Cyprus is described and illustrated. Morphologically, the new genus is similar to the genus Acaudella in respect to the lack of a cauda. Acaudella puchovi, associated with Atraphaxis caucasica (=A. buxifolia) and A. spinosa (Polygonaceae) from Uzbekistan and Israel, is re‐described and the apterous viviparous female is figured for the first time. The lectotype and paralectotypes of A. puchovi are also designated. An identification key to known species of the tribe Macrosiphini without cauda is provided. The morphological separation of B. eastopi gen. nov., sp. nov. from A. puchovi is visualized using principal component analysis.  相似文献   

19.
The jumping spider genus Onomastus Simon, 1900 is revised. Four new species: Onomastus indra sp. nov. , Onomastus kaharian sp. nov. , Onomastus pethiyagodai sp. nov. , and Onomastus rattotensis sp. nov. are described. Parsimony analysis of 26 morphological characters supported the monophyly of Onomastus. Lyssomanes is sister to Onomastus. Onomastus separates into two clades: the widespread South‐East Asia clade and the South Asia clade. The South Asia clade is restricted to the Sri Lanka–Western Ghats biodiversity hotspot. Species of the South Asia clade appear to be spot endemics, highly in danger of extinction because of habitat loss and climate change. Male palps are complex and species‐specific, suggesting rapid divergent evolution. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 711–745.  相似文献   

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