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1.
Ophichthus aphotistos, a new species of snake-eel, subfamily Ophichthinae, is described from three specimens trapped in deep water (700–800 m) off southwestern Taiwan. It is most similar toO. cruentifer but differes from it and other elongate, deep water species ofOphichthus in its vertebral number (158–162), posterior dorsal-fin origin, biserial dentition, and dark coloration. A poorly known species,Neenchelys retropinna Smith &; Böhlke, is reported from the South China Sea for the first time.  相似文献   

2.
A new loach Oreonectes guilinensis sp. nov. is described from Guangxi Zhuang Autonomous Region, China. It is the second surface-dwelling fish identified in the genus Oreonectes after the type species Oreonectes platycephalus. This new species can be distinguished from other species within the genus by the combination of the following features: a round caudal fin, 13–14 branched rays, an incomplete lateral line with 4–6 pores, a short pelvic fin located some distance from the anus, a scale-covered body, a stout build (body width 14.0%–16.7% of standard length), a posterior chamber of well-developed airbladder and a yellowish-brown body with a lateral dark brown strip. The maximum likelihood phylogenetic analysis based on cytb gene recovered this new species in a well-supported clade with the type species O. platycephalus, sister to the Lefua clade. Morphological comparisons as well as our phylogenetic tree support Oreonectes shuilongensis, Oreonectes daqikongensis, Oreonectes jiarongensis as species of Troglonectes. Based on our results there are 6 valid species in the genus Oreonectes.  相似文献   

3.
An ophichthid eel,Ophichthus megalops sp. nov., is described from the Kumano-nada, off Owase, Mie Prefecture, Japan. This species is characterized by its large eye, dorsal fin origin far behind the tip of pectoral fin, vertebral number, dentition, and a distinct black smudge on the skin sheath of anal fin near the tip of tail.  相似文献   

4.
We describe a divergent clade and three new rupicolous species of dwarf geckos of the genus Cnemaspis from the Mysore Plateau, southern India. Cnemaspis bangarasp. nov., C. graniticola sp. nov., and C.yelagiriensis sp. nov. differ from each other by 9%–18% uncorrected ND2 sequence divergence and other South Asian Cnemaspis by 17%–33% and are morphologically distinguishable from all regional congeners and each other. The new species are known from only granite boulders in montane habitats (>1,000 m asl.), just 60–120 km straight-line distance apart from each other. A fossil-calibrated timetree and ancestral area reconstructions indicate South Asian Cnemaspis originated in Western Ghats forests with initial divergence in the Paleocene-Eocene making it perhaps the oldest Indian squamate clade. Cnemaspis that occur in Peninsular India in the dry zone outside the Western Ghats form three independently derived clades that occur in significantly warmer and drier habitats than those in the Western Ghats. The discovery of a Miocene divergent clade from rocky hills on the southern edge of the Mysore Plateau reveals these habitats as novel, long-term climate refugia. This adds to the body of work revealing ancient origins of taxa in the Indian dry zone and supports the Mysore Plateau as an important and overlooked hot spot of lizard biodiversity.  相似文献   

5.
A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae), Cirrhimuraena indica sp. nov., is described based on eight specimens collected from the Paradip (Odisha) and Petuaghat harbours (West Bengal) along the Bay of Bengal. The species is distinct in having the upper jaw fringed with 16–17 cirri before posterior nostril and 4–5 in between the anterior and posterior nostrils on the side; dorsal fin originates above the level of gill opening, predorsal length is 9.3–10.9 in total length; the head is relatively large, the length is 9.3–9.8 in total length; no infraorbital pores are observed between the nostrils; teeth are numerous, small, conical and in bands on each jaw; pores are present before the gill opening 10–11 and before anus 47–48; pectoral-fin length is 2.4–2.8 in head length; predorsal vertebrae are 8–10, pre-anal vertebrae 43–47 and total vertebrae 164–169. In the maximum likelihood tree analysis for COI gene, the new species belongs to the same clade as the other congener of Cirrhimuraena chinensis and is separated from the species morphologically and genetically.  相似文献   

6.
The morphologies of two novel ciliates, Arcanisutura chongmingensis n. gen., n. sp. and Naxella paralucida n. sp., collected from Shanghai, China, have been investigated using live observation and silver staining methods. Arcanisutura n. gen. can be easily distinguished from related genera by its inconspicuous, oblique anterior suture. Arcanisutura chongmingensis n. sp. is mainly recognized by its elongated body with a tail‐like posterior end, 25–33 somatic kineties, and 4–11 excretory pores. Naxella paralucida n. sp. can be distinguished from its congeners based on its two short nassulid organelles, fusiform trichocysts, 37–49 somatic kineties, and 16 nematodesmal rods. The small‐subunit (SSU) rRNA gene sequences of these two species are presented, revealing the phylogenetic positions of Arcanisutura and Naxella. Phylogenetic analyses show that Arcanisutura forms a sister clade to other synhymeniid genera, namely, Chilodontopsis, Orthodonella, and Zosterodasys; Naxella is most closely related to Nassula spp. and is located within the monophyletic clade of the family Nassulidae.  相似文献   

7.
We used phylogenetic analyses based on multiple gene sequences (partial nr SSU and LSU rDNA, partial pt LSU rDNA, psaA and rbcL) from 148 strains (including three outgroups) and scale ultrastructure to examine phylogenetic relationships among species of the colonial genera Synura and Tessellaria. The phylogenetic tree based on the combined dataset was congruent with ultrastructural characteristics of the scales. Synura was divided into three major clades, two including species in section Synura, and one representing section Peterseniae. One clade, consisting of seven strains of S. uvella (section Synura), diverged at the base of the genus. The second clade consisted of the remaining species belonging to the section Synura. The third clade, containing organisms in the section Peterseniae and characterized by scales possessing a keel, was monophyletic with strong support values. Based on our findings, S. uvella needs to be in a separate section from other spine-bearing species, and we therefore propose new sectional ranks; Synura, Peterseniae, Curtispinae (presence of body scales with slender spines, tubular scales and caudal scales). We further propose four new species based on phylogenetic analyses and unique scale characters: S. longitubularis sp. nov., S. sungminbooi sp. nov., S. soroconopea sp. nov. and S. lanceolata sp. nov. Lastly, we propose a new genus name, Neotessella, to replace the invalid use of the name Tessellaria.  相似文献   

8.
The dinoflagellate genus Chytriodinium, an ectoparasite of copepod eggs, is reported for the first time in the North and South Atlantic Oceans. We provide the first large subunit rDNA (LSU rDNA) and Internal Transcribed Spacer 1 (ITS1) sequences, which were identical in both hemispheres for the Atlantic Chytriodinium sp. The first complete small subunit ribosomal DNA (SSU rDNA) of the Atlantic Chytriodinium sp. suggests that the specimens belong to an undescribed species. This is the first evidence of the split of the Gymnodinium clade: one for the parasitic forms of Chytriodiniaceae (Chytriodinium, Dissodinium), and other clade for the free‐living species.  相似文献   

9.
Members of the family Brachionidae are free-living organisms that range in size from 170 to 250 microns. They comprise part of the zooplankton in freshwater and marine systems worldwide. Morphologically, members of the family are characterized by a single piece loricated body without furrows, grooves, sulci or dorsal head shields, and a malleate trophi. Differences in these structures have been traditionally used to recognize 217 species that are classified into seven genera. However, the validity of the species, Plationus patulus, P. patulus macracanthus P. polyacanthus, and P. felicitas have been confused because they were alternatively assigned in Brachionus or Platyias, when considering only morphological and ecological characters. Based on scanning electron microscope (SEM) images of the trophi, these taxa were assigned in a new genus, Plationus. In this study, we examined the systematic position of P. patulus and P. patulus macracanthus using DNA sequences of two genes: the cytochrome oxidase subunit 1 (cox1) and domains D2 and D3 of the large subunit of the nuclear ribosomal RNA (LSU). In addition, the cox1 and LSU sequences representing five genera of Brachionidae (Anuraeopsis, Brachionus, Keratella, Plationus, and Platyias) plus four species of three families from the order Ploima were used as the outgroup. The maximum likelihood (ML) analyses were conducted for each individual gene as well as for the combined (cox1 + LSU) data set. The ML tree from the combined data set yielded the family Brachionidae as a monophyletic group with weak bootstrap support (<50%). Five main clades in this tree had high (>85%) bootstrap support. The first clade was composed of three populations of P. patulus + P. patulus macracanthus. The second clade was composed of a single species of Platyias. The third clade was composed of six species of Brachionus. The fourth clade included a single species of the genus Anuraeopsis, and the fifth clade was composed of three species of the genus Keratella. The genetic divergence between Plationus and Platyias ranged from 18.4 to 19.2% for cox1, and from 4.5 to 4.9% for LSU, and between Brachionus and Plationus, it ranged from 16.9 to 23.1% (cox1), and from 7.3 to 9.1% (LSU). Morphological evidence, the amount of genetic divergence, the systematic position of Plationus within the family Brachionidae, and the position of Plationus as a sister group of Brachionus and Platyias support the validity of Plationus patulus and P. patulus macracanthus into the genus Plationus.  相似文献   

10.

Parasite biodiversity of fish of the southern part of the Mediterranean sea is still incompletely explored. We describe here Microcotyle visa n. sp. from the gill filaments of the bluespotted seabream Pagrus caeruleostictus (Valenciennes) (Sparidae) collected off the Algerian coast. The identity of fish hosts was confirmed by barcoding. Microcotyle visa n. sp. is herein described and illustrated. Analysis of the cox1 gene of the monogeneans revealed minor intraspecific variation (1.4%), an order of magnitude lower than the distance between this species and other Microcotyle species (10–15 %). Microcotyle visa n. sp. is distinguished from Microcotyle erythrini van Beneden & Hesse, 1863, a congener infesting sparids, on the basis of morphological (size of clamps, number of testes) and molecular (cox1) differences. This is the fourth member of the genus known to parasitise a sparid host. A species of Paramicrocotyle sp. included in the molecular analysis was nested within a robust Microcotyle + Paramicrocotyle clade; in the absence of demonstrated molecular and morphological differences, we consider that Paramicrocotyle Caballero & Bravo-Hollis, 1972 is a junior synonym of Microcotyle van Beneden & Hesse, 1863 and transfer two species of Paramicrocotyle as Microcotyle danielcarrioni (Martinez & Barrantes, 1977) n. comb. and Microcotyle moyanoi (Villalba & Fernandes, 1986) n. comb.

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11.
Daly  Marymegan 《Hydrobiologia》2004,530(1-3):241-248
Two species of Anthopleura, A. ballii and A. thallia, co-occur in Northern Europe with Bunodosoma biscayensis, a species closely allied to Anthopleura. The historical factors underlying their distribution are here investigated as part of a preliminary phylogenetic analysis of morphological data. Based on this analysis, Bunodosoma is nested within Anthopleura, and B. biscayensis is more closely related to members of Anthopleura than to other members of Bunodosoma. Because B. biscayensis also has adhesive verrucae, rather than non-adhesive, rounded vesicles, it is transferred to Anthopleura.The tree consists of two major clades, each of which includes species from the Atlantic and the Pacific. The tree shows geographic structure: one clade includes species found only in the Northern Hemisphere, and the other includes widespread species and species found only in the Southern Hemisphere. Although all of the European species of Anthopleura are part of the Northern Hemisphere clade, none are one another’s closest relative.  相似文献   

12.
Hagfishes from New Zealand are reviewed and a phylogeny proposed using morphological and genetic data (DNA sequences of cytochrome c oxidase subunit I gene, COI, and the small subunit RNA, 16S). E ptatretus cryptus sp. nov. was previously confused with Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801) because of their similar morphology, and is found from the Three Kings Islands to Stewart Island and in the eastern part of the Chatham Rise (at depths of 96–922 m). E ptatretus poicilus sp. nov. is endemic to the Three Kings Islands, where it is common and associated with soft sediment and deep‐sea coral‐sponge habitats (114–842 m). N eomyxine caesiovitta sp. nov. is a slender hagfish found along the east coast of the North Island south to the Chatham Rise (430–1083 m). A neotype is erected for E. cirrhatus (type locality: Breaksea Sound, Fiordland), occurring widely in New Zealand coastal, shelf, and slope waters (1–922 m), but not at the Three Kings Islands. Eptatetrus goliath Mincarone & Stewart, 2006, Neomyxine biniplicata (Richardson & Jowett, 1951), and Nemamyxine elongata Richardson, 1958 are further described using additional material. Rubicundus eos (Fernholm, 1991) is still only known from the holotype (type locality: Challenger Plateau). Genetic results showed that the New Zealand Eptatretus species form a monophyletic group within the subfamily Eptatretinae, indicating likely speciation from a single common ancestor within the area. E ptatretus poicilus sp. nov. is the sister species of E. cirrhatus, and E . cryptus sp. nov. is closely associated with the clade formed by these two species. Eptatretus goliath is most closely associated with Eptatretus minor Fernholm & Hubbs, 1981 (Gulf of Mexico), these two species basally diverging within New Zealand hagfishes. The endemic genus Neomyxine forms a well‐supported monophyletic group of as yet uncertain position within the phylogenetic tree. A key to the New Zealand hagfishes, fresh colour photographs, distribution maps, and in situ video recordings are presented. © 2015 The Linnean Society of London  相似文献   

13.
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   

14.
The Empis macrorrhyncha group (Diptera: Empididae) from cool to warm temperate areas of South America and Australia is diagnosed and cladistically analysed, and five new species, Empis animosa sp.n. , E. austera sp.n. , E. maculosa sp.n. , E. occidentalis sp.n. and E. pedivillosula sp.n. , are described. Cladistic analysis of 23 adult morphological characters for 14 species of the group generated a single tree of 28 steps (CI = 0.82; RI = 0.93). Monophyly was established on the basis of a single apomorphy, possession of a bilobed cercus of the male hypopygium. Three main clades were inferred: clade 1 included three Patagonian and a single southwestern Australian species; clade 2 included two species from southeastern Australia; clade 3 included a large Patagonian group of five species and a single southeastern Australian species. The E. fulvicollis complex (clade 1) is a sister‐group of the E. macrorrhyncha complex (clades 2 + 3). A provisional historical biogeographic hypothesis is advanced correlating the appearance of the South American and Australian sister lineages with the timing of the break‐up of Gondwana.  相似文献   

15.
A morphologically distinct heliobacterium, strain HH, was isolated from Lake El Hamra, a soda lake in the Wadi El Natroun region of northwest Egypt. Strain HH consisted of ring-shaped cells that remained attached after cell division to yield coils of various lengths. Strain HH showed several of the physiological properties of known heliobacteria and grouped in the Heliorestis clade by virtue of its phylogeny and alkaliphily. The closest relative of strain HH was the filamentous alkaliphilic heliobacterium Heliorestis daurensis. However, genomic DNA:DNA hybridization results clearly indicated that strain HH was a distinct species of Heliorestis. Based on its unique phenotypic and genetic properties we describe strain HH here as a new species of the genus Heliorestis, H. convoluta sp. nov.Dedicated to Prof. Dr. Norbert Pfennig on the occasion of his 80th birthday.  相似文献   

16.
17.
Prosorhynchoides aspinosus n. sp., a new species of digenean trematode, is described based on morphological, ultrastructural and molecular data from the freshwater fish, Xenentodon cancila Hamilton, 1822, of Tuikum and Tuirial river in Mizoram, Northeast India. It differs from its congeners in the absence of tegumental spines and the length of cirrus sac. These unique morphological characteristics were further supported by the ultrastructural data showing distinct knob-like protrusions in the tegument. Each knob-like protrusion is without cutting plates or spines and appears granulated at higher magnification. The molecular data analyses, along with the sequences of other Prosorhynchoides available in the Genbank, using internal transcribed spacer 2 and 28S rDNA revealed a gap of 4% K2P (Kimura 2 parameter) distance with its closest congener, P. karvei, confirming the novelty of the species, and thus, clearly differentiates the new species from all other valid Prosorhynchoides spp.  相似文献   

18.
To infer the monophyletic origin and phylogenetic relationships of the order Desmoscolecida, a unique and puzzling group of mainly free-living marine nematodes, we newly determined nearly complete 18S rDNA sequences for six marine desmoscolecid nematodes belonging to four genera (Desmoscolex, Greeffiella, Tricoma and Paratricoma). Based on the present data and those of 72 nematode species previously reported, the first molecular phylogenetic analysis focusing on Desmoscolecida was done by using neighbor joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods. All four resultant trees consistently and strongly supported that the family Desmoscolecidae forms a monophyletic group with very high node confidence values. The monophyletic clade of desmocolecid nematodes was placed as a sister group of the clade including some members of Monhysterida and Araeolaimida, Cyartonema elegans (Cyartonematidae) and Terschellingia longicaudata (Linhomoeidae) in all the analyses. However, the present phylogenetic trees do not show any direct attraction between the families Desmoscolecidae and Cyartonematidae. Within the monophyletic clade of the family Desmoscolecidae in all of the present phylogenetic trees, there were consistently observed two distinct sub-groups which correspond to the subfamilies Desmoscolecinae [Greeffiella sp. + Desmoscolex sp.] and Tricominae [Paratricoma sp. + Tricoma sp].  相似文献   

19.
20.
Enteropneusts in the family Torquaratoridae were imaged using still and video cameras in the deep North Atlantic and then collected by remotely operated vehicles. From this material, we describe Yoda purpurata n. gen, n. sp., Tergivelum cinnabarinum n. sp., and Allapasus isidis n. sp. Individuals of the first two species were browsing completely exposed on the sea floor, whereas the specimen of the last species was encountered floating ~1 m above the sea floor. Living specimens of Y. purpurata were 12–19 cm long and had a dark reddish‐purple proboscis, collar, and genital wings (folded dorsally over the anterior region of the trunk). Members of this species were hermaphrodites (the first ever discovered in the phylum Hemichordata), with numerous separate testes and ovaries in the genital wings. Living specimens of T. cinnabarinum were 12–26 cm long and had a cinnabar‐colored proboscis, collar, and back veils (arising from the anterior region of the trunk); sexes were separate, and body shape and internal morphology closely resemble those of its brown congener, T. baldwinae, from the eastern Pacific. The only specimen of A. isidis collected was a male 13 cm long and pale yellow when alive. Its body shape was proportionally shorter and broader than that of its orange congener, A. aurantiacus, from the eastern Pacific, but the internal anatomy of the two species is virtually identical. [Correction made after online publication August 21, 2012 to correct species name in preceding sentence.]  相似文献   

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