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1.
Syst Biol ; 70(6): 1110-1122, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33367903

RESUMO

The segmented trapdoor spiders (Liphistiidae) are the sole surviving family of the suborder Mesothelae, which forms the sister lineage to all other living spiders. Liphistiids have retained a number of plesiomorphic traits and their present-day distribution is limited to East and Southeast Asia. Studying this group has the potential to shed light on the deep evolutionary history of spiders, but the phylogeny and divergence times of the family have not been resolved with confidence. We performed phylogenomic and molecular dating analyses of 2765 ultraconserved element loci from 185 liphistiid taxa. Our analyses show that the crown group of Liphistiidae appeared in the mid-Cretaceous at 102 Ma (95% credibility interval 92-113 Ma), but it was not until the Neogene that much of the diversification within the family occurred in mainland Southeast and East Asia. This diversification was coincident with tectonic events such as the extension of the East Asian continental margin, as well as geological upheavals in Indochina induced by the collision between India and Asia. Our study highlights the important role of major tectonic events in shaping the evolutionary history, present-day diversity, and geographical distribution of mesothele and liphistiid spiders. [biogeography; concatenation; Liphistiidae; molecular dating; summary coalescent; UCEs.].


Assuntos
Evolução Biológica , Aranhas , Animais , Ásia , Ásia Oriental , Filogenia , Filogeografia , Aranhas/genética
2.
Mol Phylogenet Evol ; 151: 106900, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32599078

RESUMO

Determining species boundaries forms an important foundation for biological research. However, the results of molecular species delimitation can vary with the data sets and methods that are used. Here we use a two-step approach to delimit species in the genus Heptathela, a group of primitively segmented trapdoor spiders that are endemic to Japanese islands. Morphological evidence suggests the existence of 19 species in the genus. We tested this initial species hypothesis by using six molecular species-delimitation methods to analyse 180 mitochondrial COI sequences of Heptathela sampled from across the known range of the genus. We then conducted a set of more focused analyses by sampling additional genetic markers from the subset of taxa that were inconsistently delimited by the single-locus analyses of mitochondrial DNA. Multilocus species delimitation was performed using two Bayesian approaches based on the multispecies coalescent. Our approach identified 20 putative species among the 180 sampled individuals of Heptathela. We suggest that our two-step approach provides an efficient strategy for delimiting species while minimizing costs and computational time.


Assuntos
Ilhas , Aranhas/genética , Animais , Teorema de Bayes , Código de Barras de DNA Taxonômico , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Geografia , Japão , Funções Verossimilhança , Mitocôndrias/genética , Filogenia , Probabilidade , Especificidade da Espécie
3.
Proc Biol Sci ; 282(1808): 20142486, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25948684

RESUMO

Living fossils are lineages that have retained plesiomorphic traits through long time periods. It is expected that such lineages have both originated and diversified long ago. Such expectations have recently been challenged in some textbook examples of living fossils, notably in extant cycads and coelacanths. Using a phylogenetic approach, we tested the patterns of the origin and diversification of liphistiid spiders, a clade of spiders considered to be living fossils due to their retention of arachnid plesiomorphies and their exclusive grouping in Mesothelae, an ancient clade sister to all modern spiders. Facilitated by original sampling throughout their Asian range, we here provide the phylogenetic framework necessary for reconstructing liphistiid biogeographic history. All phylogenetic analyses support the monophyly of Liphistiidae and of eight genera. As the fossil evidence supports a Carboniferous Euramerican origin of Mesothelae, our dating analyses postulate a long eastward over-land dispersal towards the Asian origin of Liphistiidae during the Palaeogene (39-58 Ma). Contrary to expectations, diversification within extant liphistiid genera is relatively recent, in the Neogene and Late Palaeogene (4-24 Ma). While no over-water dispersal events are needed to explain their evolutionary history, the history of liphistiid spiders has the potential to play prominently in vicariant biogeographic studies.


Assuntos
Proteínas de Artrópodes/genética , Evolução Biológica , Filogenia , Aranhas/classificação , Aranhas/genética , Animais , Sudeste Asiático , Ásia Oriental , Dados de Sequência Molecular , Análise de Sequência de DNA
4.
Zookeys ; 1189: 203-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38314109

RESUMO

Seven new species of the primitive segmented spider genus Liphistius are described and assigned to species groups based on characters of the male palp and vulva plate. The bristowei group includes L.dawei Sivayyapram & Warrit, sp. nov. (♂♀) from southeastern Myanmar, L.choosaki Sivayyapram & Warrit, sp. nov. (♀) from northwestern Thailand, and L.lansak Sivayyapram & Warrit, sp. nov. (♀) from western Thailand; the trang group (Complex A) contains L.kaengkhoi Sivayyapram & Warrit, sp. nov. (♂♀), L.hintung Sivayyapram & Warrit, sp. nov. (♂♀), L.buyphradi Sivayyapram & Warrit, sp. nov. (♂♀), and L.champakpheaw Sivayyapram & Warrit, sp. nov. (♂♀) from central Thailand.

5.
Zootaxa ; 4984(1): 274280, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34186682

RESUMO

The gnaphosid spider Coillina baka Yin Peng, 1998, originally described from Yunnan, China is newly recorded from Chin State, Myanmar. While its holotype (male) was the only known record of the spider so far, the female is described and illustrated herein for the first time. The detailed structures of the male palp and female genitalia of this species are depicted, and its possible relationship with some species of Synaphosus Platnick Shadab, 1980 is briefly discussed.


Assuntos
Aranhas/classificação , Animais , China , Feminino , Masculino , Mianmar , Aranhas/anatomia & histologia
6.
Zookeys ; 888: 1-50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754317

RESUMO

Among the eight extant genera of primitively segmented spiders, family Liphistiidae, two are confined to East Asian islands, Heptathela Kishida, 1923 and Ryuthela Haupt, 1983. In this paper, a taxonomic revision of the genus Heptathela (Heptathelinae) from Kyushu and Ryukyu archipelago, Japan is provided. This study follows a multi-tier species delimitation strategy within an integrative taxonomic framework that is presented in a parallel paper, in which diagnosable lineages are considered as valid species. There, the initial hypothesis of species diversity (19) based on classical morphological diagnoses is tested with multiple species delimitation methods aimed at resolving conflict in data. This revision follows those analyses that converge on the species diversity of 20, which includes a pair of cryptic species that would have been undetected with morphology alone. After this revision, eight previously described species remain valid, two junior synonyms are proposed, and 12 new Heptathela species are described based on diagnostic evidence. To ease identification and to hint at putative evolutionary units, Heptathela is divided into three groups. The Kyushu group contains H. higoensis Haupt, 1983, H. kikuyai Ono, 1998, H. kimurai (Kishida, 1920), and H. yakushimaensis Ono, 1998; the Amami group contains H. amamiensis Haupt, 1983, H. kanenoi Ono, 1996, H. kojima sp. nov., H. sumiyo sp. nov., and H. uken sp. nov.; and the Okinawa group contains H. yanbaruensis Haupt, 1983, H. aha sp. nov., H. gayozan sp. nov., H. kubayama sp. nov., H. mae sp. nov., H. otoha sp. nov., H. shuri sp. nov., H. tokashiki sp. nov., H. unten sp. nov., and H. crypta sp. nov. Heptathela helios Tanikawa & Miyashita, 2014 is not assigned to a species group. A combination of diagnostic tools augments the morphological diagnoses that, in isolation, would be prone to error in morphologically challenging groups of organisms.

7.
Zootaxa ; 4545(3): 444-446, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30790913

RESUMO

Modern taxonomy and systematics profit from an invaluable tool that has been developed in the course of more than a century by intense discussions and negotiations of generations of zoologists and palaeontologists: The International Code of Zoological Nomenclature (ICZN 1999, 2012). The main goal of the Code is "to promote stability and universality in the scientific names of animals and to ensure that the name of each taxon is unique and distinct" (Melville 1995, ICZN 1999: 2). The provisions of the Code are generally accepted and thoroughly applied by the scientific community. Exceptions, such as the one described below, are very rare.


Assuntos
Aracnídeos , Aranhas , Animais
8.
Zookeys ; (481): 39-56, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25685031

RESUMO

The present paper gives a review of Solenysa species from Japan and provides a solution for the species bearing the generotype name Solenysamellotteei Simon, 1894. A total of six species are recorded, including two new species Solenysamacrodonta sp. n. and Solenysatrunciformis sp. n. The species collected from Kawasaki (NSMT-Ar 11154) and Hachioji should be the generotype Solenysamellotteei, with Solenysaakihisai Tu, 2011, syn. n. as its junior synonym. To distinguish these congeneric species from each other, their genital characters are provided in detail based on images collected by scanning electron microscopy and light microscopy.

9.
Zookeys ; (488): 121-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25878527

RESUMO

The spider suborder Mesothelae, containing a single extant family Liphistiidae, represents a species-poor and ancient lineage. These are conspicuous spiders that primitively retain a segmented abdomen and appendage-like spinnerets. While their classification history is nearly devoid of phylogenetic hypotheses, we here revise liphistiid genus level taxonomy based on original sampling throughout their Asian range, and on the evidence from a novel molecular phylogeny. By combining morphological and natural history evidence with phylogenetic relationships in the companion paper, we provide strong support for the monophyly of Liphistiidae, and the two subfamilies Liphistiinae and Heptathelinae. While the former only contains Liphistius Schiödte, 1849, a genus distributed in Indonesia (Sumatra), Laos, Malaysia, Myanmar, Thailand, we recognize and diagnose seven heptatheline genera, all but three removed from the synonymy of Heptathela: i) Ganthela Xu & Kuntner, gen. n. with the type species Ganthelayundingensis Xu, sp. n. is known from Fujian and Jiangxi, China; ii) a rediagnosed Heptathela Kishida, 1923 is confined to the Japanese islands (Kyushu and Okinawa); iii) Qiongthela Xu & Kuntner, gen. n. with the type species Qiongthelabaishensis Xu, sp. n. is distributed disjunctly in Hainan, China and Vietnam; iv) Ryuthela Haupt, 1983 is confined to the Ryukyu archipelago (Japan); v) Sinothela Haupt, 2003 inhabits Chinese areas north of Yangtze; vi) Songthela Ono, 2000 inhabits southwest China and northern Vietnam; and vii) Vinathela Ono, 2000 (Abcathela Ono, 2000, syn. n.; Nanthela Haupt, 2003, syn. n.) is known from southeast China and Vietnam.

10.
Am Heart J ; 148(4): E15, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15459610

RESUMO

BACKGROUND: Early reperfusion therapy improves the clinical outcomes of patients with acute myocardial infarction (AMI), but benefits are limited by reperfusion injury in some patients. We examined the effect of nicorandil, a hybrid of K(ATP) channel opener and nicotinamide nitrate, on reactive oxygen species (ROS) formation and clinical outcomes after primary percutaneous coronary intervention (PCI) for AMI. METHODS: Fifty-eight patients with AMI were randomized into control (n = 25) and nicorandil pretreatment groups (n = 33). In the nicorandil group, nicorandil (4 mg as a bolus injection followed by constant infusion at 8 mg/hour for 24 hours) was administered just after admission. ROS formation was assessed by measuring urinary excretion of 8-epi-prostaglandin F2alpha (PGF2alpha) and compared between the 2 groups. Cardiac function and the incidence of reperfusion injury and cardiac events were also compared. RESULTS: Urinary 8-epi-PGF2alpha excretion was increased 2-fold at 60 to 90 minutes after PCI in the control group, whereas it was unchanged after PCI in the nicorandil group (P <.0001 between the 2 groups). The incidence of no-reflow phenomenon was lower in the nicorandil group than in the control group. Left ventricular ejection fraction and cardiac index at 6 months were greater in the nicorandil group than in controls. Plasma brain natriuretic peptide level at 6 months was lower in the nicorandil group. Incidences of inhospital cardiac events and rehospitalization were lower in the nicorandil group than in controls. CONCLUSIONS: Nicorandil improves cardiac function and clinical outcomes in patients with AMI. Suppression of ROS formation may be involved in the mechanism.


Assuntos
Angioplastia Coronária com Balão , Dinoprosta/análogos & derivados , Infarto do Miocárdio/tratamento farmacológico , Nicorandil/uso terapêutico , Pré-Medicação , Espécies Reativas de Oxigênio/metabolismo , Vasodilatadores/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Terapia Combinada , Dinoprosta/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Nicorandil/farmacologia , Pressão Propulsora Pulmonar , Volume Sistólico , Resultado do Tratamento , Vasodilatadores/farmacologia
11.
Heart Vessels ; 22(5): 303-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17879021

RESUMO

Nicorandil, a hybrid KATP channel opener and nicotinamide nitrate, reduces no-reflow phenomenon and improves cardiac function in patients with acute myocardial infarction (AMI). We reported that nicorandil suppresses radical formation in patients with AMI undergoing primary percutaneous coronary intervention (PCI). In the present study, we tested the hypothesis that nicorandil treatment suppresses MMP activities and predicts ventricular remodeling in AMI. Sixty-two patients with AMI were randomized into nicorandil pretreatment (n = 31) and control (n = 31) groups after admission and underwent primary PCI. Nicorandil was administered as a bolus injection (4 mg) followed by constant infusion (8 mg/h) for 24 h just after admission. On days 1, 2, and 14 after the onset of AMI, the plasma levels of matrix metalloproteinase (MMP)-2 and MMP-9 were measured by enzyme-linked immunosorbent assay and the activities by gelatin zymography. There were no differences in the baseline clinical characteristics between the two groups. On day 1, there were no differences in both MMP-2 and MMP-9 levels and their activities between the two groups. However, both MMP-2 and MMP-9 levels and their activities were significantly lower in nicorandil than in control group on day 2 (MMP-2 level, 1 014 +/- 39 vs 1 174 +/- 44 ng/ml; MMP-9 level, 17 +/- 1 vs 23 +/- 2 ng/ml; both P < 005) and on day l4 (MMP-2 level, 970 +/- 38 vs 1 221 +/- 44 ng/ml; MMP-9 level, 17 +/- 1 vs 23 +/- 1 ng/ml; both P < 0.05). Left ventricular end-diastolic volume index (LVEDVI) at acute phase was not different between the two groups. At 6 months after AMI, LVEDVI was significantly smaller in nicorandil than in the control group (83 +/- 4 vs 96 +/- 4 ml/m2, P < 0.05). The change in LVEDVI from acute phase to 6 months was positively correlated with MMP-2 and MMP-9 levels and activities. Nicorandil suppresses the increases in MMP levels and activities and prevents the development of ventricular remodeling in AMI.


Assuntos
Regulação da Expressão Gênica , Metaloproteinases da Matriz/sangue , Infarto do Miocárdio/sangue , Nicorandil/farmacologia , Vasodilatadores/farmacologia , Remodelação Ventricular , Doença Aguda , Idoso , Angiografia/métodos , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Pessoa de Meia-Idade
12.
Eur Heart J ; 24(24): 2180-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14659769

RESUMO

AIMS: Oxidative stress is implicated in the progression of heart failure, and matrix metalloproteinase (MMP) activity is increased in patients with congestive heart failure. We examined the role of oxidative stress on MMP activity in humans. METHODS AND RESULTS: We measured the MMP activity and the level of 8-iso-prostagandin F2alpha (8-iso-PGF2alpha), a specific and quantitative maker of oxidant stress, in the pericardial fluid (PF) in 47 consecutive patients with coronary artery disease who underwent coronary artery bypass surgery. Zymography of PF showed bands at 92-85kDa (MMP-9) and 72-65kDa (MMP-2). The MMP activity was expressed as the ratio to MMP-2 standard. MMP-2, MMP-9 and total gelatinolysis activities were positively correlated with left ventricular end-diastolic volume index (LVEDVI), and MMP-2 and total gelatinolysis activities were also positively correlated with LV end-systolic volume index. Moreover, MMP-2, MMP-9 and total gelatinolysis activities were all positively correlated with pericardial level of 8-iso-PGF2alpha. Also, LVDEVI was positively correlated with pericardial level of 8-iso-PGF2alpha. CONCLUSIONS: Oxidative stress may play an important role in the regulation of MMP activity. Augmented MMP activity may be involved in the development of ventricular remodelling in patients with coronary artery disease.


Assuntos
Doença da Artéria Coronariana/etiologia , Metaloproteinases da Matriz/metabolismo , Estresse Oxidativo/fisiologia , Remodelação Ventricular/fisiologia , Idoso , Doença da Artéria Coronariana/enzimologia , Feminino , Humanos , Masculino , Pericárdio/química , Prostaglandinas A/análise
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