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1.
ABSTRACT

A revision of Chinese freshwater Sulcospira gastropods is presented here based on analysis of the morphological characteristics and partial sequences of the mitochondrial genes 16S rRNA and cytochrome c oxidase subunit I (COI). A total of three species was reported in China by earlier authors, including Sulcospira hainanensis, S. hunanensis and S. paludiformis. In this study, two new species of Sulcospira are described from Hunan Province and Guangxi Zhuang Autonomous Region based on morphological and molecular evidence.  相似文献   

2.
Molecular analyses, in combination with morphological studies, provide invaluable tools for delineating red algal taxa. However, molecular datasets are incomplete and taxonomic revisions are often required once additional species or populations are sequenced. The small red alga Conferva parasitica was described from the British Isles in 1762 and then reported from other parts of Europe. Conferva parasitica was traditionally included in the genus Pterosiphonia (type species P. cloiophylla in Schmitz and Falkenberg 1897), based on its morphological characters, and later transferred to Symphyocladia and finally to Symphyocladiella using molecular data from an Iberian specimen. However, although morphological differences have been observed between specimens of Symphyocladiella parasitica from northern and southern Europe they have yet to be investigated in a phylogenetic context. In this study, we collected specimens from both regions, studied their morphology and analyzed rbcL and cox1 DNA sequences. We determined the phylogenetic position of a British specimen using a phylogenomic approach based on mitochondrial and plastid genomes. Northern and southern European populations attributed to S. parasitica represent different species. Symphyocladiella arecina sp. nov. is proposed for specimens from southern Europe, but British specimens were resolved as a distant sister lineage to the morphologically distinctive Amplisiphonia, so we propose the new genus Deltalsia for this species. Our study highlights the relevance of using materials collected close to the type localities for taxonomic reassessments, and showcases the utility of genome-based phylogenies for resolving classification issues in the red algae.  相似文献   

3.
Interspecific systematics in the red algal order Sporolithales remains problematic. To re‐evaluate its species, DNA analyses were performed on historical type material and recently collected specimens assigned to the two genera Sporolithon and Heydrichia. Partial rbcL sequences from the lectotype specimens of Sporolithon ptychoides (the generitype species) and Sporolithon molle, both from El Tor, Egypt, are exact matches to field‐collected topotype specimens. Sporolithon crassum and Sporolithon erythraeum also have the same type locality; material of the former appears to no longer exist, and we were unable to PCR amplify DNA from the latter. A new species, Sporolithon eltorensis, is described from the same type locality. We have not found any morpho‐anatomical characters that distinguish these three species. No sequenced specimens reported as S. ptychoides from other parts of the world represent this species, and likely reports of S. ptychoides and S. molle based on morpho‐anatomy are incorrect. A partial rbcL sequence from the holotype of Sporolithon dimotum indicates it is not a synonym of S. ptychoides, and data from the holotype of S. episporum confirm its specific recognition. DNA sequences from topotype material of Heydrichia woelkerlingii, the generitype species, and isotype material of Heydrichia cerasina confirm that these are distinct species; the taxon reported to be H. woelkerlingii from New Zealand is likely an undescribed species. Type specimens of all other Sporolithon and Heydrichia species need to be sequenced to confirm that they are distinct species; morpho‐anatomical studies have proved inadequate for this task.  相似文献   

4.
Abstract

Neotrombicula naultini (Dumbleton, 1947) was redescribed from the type specimen and additional specimens collected off Hoplodactylus granulatus (= Dactylocnemus granulatus), Hoplodactylus maculatus, and Hoplodactylus pacificus in New Zealand. Neotrombicula sphenodonti and Microtrombicula hoplodactyla were described, as new species, from specimens collected from New Zealand reptiles.  相似文献   

5.
6.
7.
Paraliparis hawaiiensis n.sp. is described from the north‐western Hawaiian Islands from two specimens collected at 2196 and 3055 m. It differs from other North Pacific Ocean species in its chin pore arrangement, tooth pattern and body proportions. Although liparid specimens have previously been collected from Hawaii, they were undescribed and are now lost. Therefore, this is the first liparid species described from the archipelago. In situ photographs of Hawaiian snailfishes are also shown and discussed here.  相似文献   

8.
塔里木盆地塔中台地奥陶系海百合茎化石丰富。本文通过研究塔中35井上奥陶统良里塔格组和桑塔木组岩芯中的海百合与其共生生物的关系, 讨论了海百合化石的古生态。在塔中35井上奥陶统取芯中识别出7种海百合茎类型: 圆圆茎、星星茎、星圆茎、椭圆圆茎、星椭圆茎、圆角星星茎和不规则星茎, 根据茎板形态划分为五射茎板组(Pentameri)、椭圆茎板组(Elliptici)、圆茎板组(Cyclici)、特殊茎板组(Varii)四种组合类型; 统计了海百合茎化石各种切面的大小和百分含量; 结合岩性分析了每段地层的沉积环境。研究发现, 在局限泻湖环境下, 蓝细菌–四分珊瑚为主的生物组合中不见海百合化石碎片; 仅见腹足类和介壳类化石的细砂屑滩中, 偶见细小的海百合茎化石; 在开阔海环境中, 海百合广泛与苔藓虫、管孔藻、粗枝藻等共生。在海百合–苔藓虫组合中, 海百合茎板的类型最丰富多样, 五射茎板组、椭圆茎板组、圆茎板组、特殊茎板组等四种茎板组合类型都存在; 在管孔藻–海百合组合中, 海百合茎板主要为圆茎板类型, 粗大、密集, 海百合茎碎片含量最高; 在海百合–粗枝藻组合中, 海百合茎板的数量减少、大小变小, 但茎板的类型比较丰富, 四种茎板组合类型都有。由此认为, 塔中台地上奥陶统沉积期, 海百合生长的首选环境为开阔台地, 并受水动力能量和水体清洁度控制: 水动力能量高, 水体清洁, 海百合繁盛; 水动力能量低, 水体动荡浑浊, 海百合可以生存; 水动力能量低、较为动荡、微生物席发育的环境, 不利于海百合生存。  相似文献   

9.
在安徽省萧县凤凰山剖面炒米店组中上部(江山阶上部到第十阶)岩层中采得丰富的索克虫科三叶虫标本。共计4属6种(含2新种), 包括Eosaukia bella (Walcott, 1906)、E. anhuiensis sp. nov.、Lophosaukia orientalis (Kobayashi, 1933)、Prosaukia campe (Walcott, 1905)和P. xiaoxianensis sp. nov.、Lichengia onigawara Kobayashi, 1942。在对属征进行修订与讨论的基础上, 通过对比这些属的模式种及其他种, 对4个旧种进行了再研究和种征厘定, 最后对这6个种的谱系关系展开了简要讨论。  相似文献   

10.
Abstract

Holcoperla magna n.sp. is described and figured from material collected on Headlong Peak, Mt Aspiring National Park. New information is given on H. angularis (Wisely) and H. jacksoni McLellan, and the 3 species are compared. Larvae designated as type specimens of H. angularis are shown to be Apteryoperla monticola Wisely.  相似文献   

11.
A large adult (138 mm head length) of the grenadier genus Coryphaenoides is described. It is identified as C. affinis hitherto known only from two juvenile type specimens collected by HMS Challenger off Uruguay in 1876. The diagnosis of the species is revised to include the discovery of considerable ontogenetic changes in squamation. Spinulation on the body scales are reduced or lost with size, while the armament of the head scales become amplified. The larger of the syntype specimens is designated as the lectotype. All three known specimens of C. affinis were collected in the southwestern Atlantic at depths between 3500 and 4000 m. A key for identification for the species of the subgenus Nematonurus is provided.  相似文献   

12.
Ciona intestinalis is considered a widespread and easily recognizable tunicate, the sister group of vertebrates. In recent years, molecular studies suggested that C. intestinalis includes at least two cryptic species, named ‘type A’ and ‘type B’, morphologically indistinguishable. It is dramatic to certify that two different species may be hidden under the name of a species widely used as a model species in biological researches. This raised the problem of identifying diagnostic morphological characters capable of distinguishing these types. We compared the morphology of specimens belonging to the two types and found that only type A specimens possess tunic tubercular prominences, allowing unambiguous discrimination. Remarkably, these structures were already described as distinctive of the Japanese species Ciona robusta, Hoshino and Tokioka, 1967; later synonymized under C. intestinalis (sensu Millar, 1953). In this study, we have confirmed that C. intestinalis type A corresponds to C. robusta. Based on the geographic distribution of C. intestinalis type B, and considering that the original C. intestinalis species was described from North European waters, we determined that C. intestinalis type B corresponds to C. intestinalis as described by Millar in 1953 and possibly to Linnaeus' Ascidia intestinalis L., 1767 for which we have deposited a neotype (from Roscoff, France) and for which we retain the name Ciona intestinalis (Linnaeus, 1767).  相似文献   

13.
A new genusSpiniferomonas of the Synuraceae was established withSpiniferomonas bourrellii as the type species. The cells ofSpiniferomonas are solitary, freeswimming, biflagellated, and covered with siliceous scales and spines. The genus shows a similarity to theChrysosphaerella (Synuraceae) in the structure of scales and spines. In addition to the type species, six species were also described as the new taxa of this genus. They were named asS. abei, S. bilacunosa, S. trioralis, S. crucigera, S. conica, andS. alata, respectively. All the specimens were collected from ponds and lakes in Japan.S. trioralis was also collected from the Republic of South Africa. Dedicated to Professor Dr. NoboruAbe in celebration of his sixty-fifth birthday.  相似文献   

14.
Several species of the family Petraliellidae were first described from the coast of Queensland, including the type species of Sinupetraliella, S. litoralis. These species are redescribed from type, or topotype specimens, and include Petraliella concinna, which has not been certainly found since its introduction in 1891; lectotype material is designated for P. buski and P. magna. Six other species are described from Queensland, P. crassocirca, P. dentilabris, P. dorsiporosa, Mucropetraliella bennetti, M. serrata and M. tuberosa. The species Mucropetraliella tuberosa is a new addition to the Queensland fauna and is described and illustrated here for the first time since its introduction in 1884. The characters of the family Petraliellidae are briefly discussed and the genera to which the Queensland species are assigned is reviewed. A taxonomic key to the ten Queensland petraliellid species described is also provided.  相似文献   

15.
Two catarrhine mandibles and five isolated teeth have been discovered from Early Miocene localities in Western Kenya. One mandible comes from the well‐known locality of Songhor whereas the other is from a newly discovered locality, Lower Kapurtay, located near Songhor. The mandibles both can clearly be assigned to the species Rangwapithecus gordoni based on molar morphology, which is unique among Early Miocene catarrhines. The isolated specimens can be assigned to Rangwapithecus based on their similarities in morphology to the homologues preserved in the two mandibles. These specimens provide important new information about the dentognathic morphology of Rangwapithecus, which is described in detail. The mandible from Songhor (KNM‐SO 22228) represents the first definitive female mandible of Rangwapithecus. The Lower Kapurtay mandible (KNM‐KT 31234) appears to be male but is much smaller than another recently described male mandible of this species (KNM‐SO 17500) and the type maxilla (KNM‐SO 700). These specimens enable a reassessment of the attributions of all other mandibles and isolated lower teeth of Rangwapithecus, and we present a complete hypodigm of the mandibular and lower dental material for the species. Finally, we provide some additions to the diagnosis of Rangwapithecus gordoni based on previously unknown morphology. Am J Phys Anthropol 153:341–352, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
‘Ana‐aosa’, one of the most common marine green algae in Japan, was described as Ulva pertusa Kjellman in 1897 from Hakodate in northern Japan. Ulva pertusa was considered to be a temperate species, with its native distributional range restricted to northeastern Asia. Although this species has been reported from various regions outside northeastern Asia, these records have been explained as non‐indigenous populations. Recently, on the basis of genetic data and nomenclatural priority, U. pertusa was synonymized with U. australis Areschoug, a species described in 1851 from specimens collected in South Australia. Based on genetic studies, Australian populations identified as U. pertusa had been considered to have originated from Japan. However, the published genetic data on U. australis in Australia have been based only on recent collections and no historical specimens have been examined. We tested the hypothesis that native (true) U. australis is an independent species of very similar morphology to U. pertusa, but that its natural domination of shoreline habitats has been suppressed by introduced populations of U. pertusa from Asia. In the present study, we extracted DNA from the type specimen of U. australis housed in the Swedish Museum of Natural History (S) and obtained DNA sequences of the chloroplast rbcL gene and the nuclear rDNA ITS2 region. Our results show that U. australis and U. pertusa are genetically virtually identical, confirming that U. pertusa is a synonym of U. australis. This suggests that the introduction of U. australis to Australia occurred by the middle of the 19th century, when the type was collected and before there was a direct shipping route between Japan and Australia. We speculate that the introduction of U. australis to Australia occurred as a secondary introduction from non‐indigenous populations in northeastern Asia, but not directly from Japan.  相似文献   

17.
Phylogeny reconstructions based on mtDNA and nDNA have become the standard in studies on relationships between taxa. Difficulties in obtaining material, for example because of small endemic distributions, often lead to gaps in datasets. Collections in natural history museums can provide us with material to fill these gaps, but extracting DNA from historical specimens can be challenging. We used a PCR protocol for small amounts of sample material and high PCR yield on eggs of specimens of the coral‐dwelling gall crab family Cryptochiridae collected in 1984, including material from the eastern Atlantic species Detocarcinus balssi. We obtained DNA sequences from seven older museum specimens using newly developed primers, which we combined with COI sequences from recently collected material. Results show that D. balssi is closest to the Indo‐Pacific species Utinomiella dimorpha and not closely related to one of the other three Atlantic Cryptochiridae species. The remaining newly acquired DNA sequences from museum material cluster with the respective sequences from recently collected specimens.  相似文献   

18.
During a floristic survey in the Belgaum district, Karnataka state, some specimens of Rotala L. were collected from a lateritic plateau in western Ghats, India. The specimens did not match with any previously described species of Rotala, but closely resembled R. macrandra Koehne and R. rosea (Poir.) C. D. K. Cook ex H. Hara in their exserted stamens and styles. The new species is described and illustrated here as Rotala belgaumensis S. R. Yadav, Malpure & Chandore.  相似文献   

19.
During a botanic expedition in 2013 to study the taxonomy of the genus Manihot in the Cerrado biome, numerous specimens were collected in the Chapada dos Veadeiros region, in central Brazil. After careful analyses, two new species of this genus were discovered. Manihot gratiosa and M. lourdesii are herein described and illustrated. Both species can be distinguished from morphologically similar species by a combination of characters such as shape and overlapping of leaf lobes, indumentum, type and aspect of inflorescence, integrity of pistillate sepals, as well as shape, integrity, and size of bracts of both male and female flowers.  相似文献   

20.
Evidence suggests that truffle-like sporocarp forms have evolved many times in the Pezizales, but primarily from epigeous ancestors within ectomycorrhizal clades. There are several ectomycorrhizal clades, however, that contain no known hypogeous species. We collected specimens of an unusual unidentified truffle from mixed oak woodlands in Iowa. Although clearly a member of the Pezizales (Ascomycota), this hypogeous species did not belong to any of the described truffle genera. Based on a combination of ecological, phylogenetic, and morphological evidence we determined that this new truffle is a hypogeous member of the genus Otidea (Pyronemataceae), a lineage with no described truffle species. We describe it here as a new species, Otidea subterranea.  相似文献   

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