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1.
Syst Biol ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733598

RESUMO

Asymmetrical rates of cladogenesis and extinction abound in the Tree of Life, resulting in numerous minute clades that are dwarfed by larger sister groups. Such taxa are commonly regarded as phylogenetic relicts or "living fossils" when they exhibit an ancient first appearance in the fossil record and prolonged external morphological stasis, particularly in comparison to their more diversified sister groups. Due to their special status, various phylogenetic relicts tend to be well-studied and prioritized for conservation. A notable exception to this trend is found within Amblypygi ("whip spiders"), a visually striking order of functionally hexapodous arachnids that are notable for their antenniform first walking leg pair (the eponymous "whips"). Paleoamblypygi, the putative sister group to the remaining Amblypygi, is known from Late Carboniferous and Eocene deposits, but is survived by a single living species, Paracharon caecus Hansen, 1921, that was last collected in 1899. Due to the absence of genomic sequence-grade tissue for this vital taxon, there is no global molecular phylogeny for Amblypygi to date, nor a fossil-calibrated estimation of divergences within the group. Here, we report a previously unknown species of Paleoamblypygi from a cave site in Colombia. Capitalizing upon this discovery, we generated the first molecular phylogeny of Amblypygi, integrating ultraconserved element sequencing with legacy Sanger datasets and including described extant genera. To quantify the impact of sampling Paleoamblypygi on divergence time estimation, we performed in silico experiments with pruning of Paracharon. We demonstrate that the omission of relicts has a significant impact on the accuracy of node dating approaches that outweighs the impact of excluding ingroup fossils, which bears upon the ancestral range reconstruction for the group. Our results underscore the imperative for biodiversity discovery efforts in elucidating the phylogenetic relationships of "dark taxa", and especially phylogenetic relicts in tropical and subtropical habitats. The lack of reciprocal monophyly for Charontidae and Charinidae leads us to subsume them into one family, Charontidae, new synonymy.

2.
Mol Phylogenet Evol ; 191: 107989, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072141

RESUMO

The systematics of the arachnid order Solifugae have been an enigma, owing to challenges in interpreting morphology, a paucity of molecular phylogenetic studies sampling across the group, and a dearth of taxonomic attention for many lineages. Recent work has suggested that solifuge families largely exhibit contiguous distributions and reflect patterns of vicariance, with the exception of three families: Melanoblossidae, Daesiidae and Gylippidae. Morphological studies have cast doubt on their existing circumscriptions and the present composition of these taxa renders their distributions as disjunct. We leveraged ultraconserved elements (UCEs) to test the phylogenetic placement of three key lineages of Solifugae that cause these anomalous distributions: Dinorhax rostrumpsittaci (putative melanoblossid), Namibesia (putative daesiid), and Trichotoma (putative gylippid). Phylogenetic placement of these three genera based on UCEs rendered the families that harbor them as para- or polyphyletic, recovering instead relationships that better accord with a biogeographic history driven by vicariance. Toward a stable and phylogenetically informed classification of Solifugae, we establish three new families, Dinorhaxidae new rank, Namibesiidae new rank and Lipophagidae new rank.


Assuntos
Aracnídeos , Aranhas , Animais , Filogenia , Camelus , Aranhas/genética
3.
Cladistics ; 39(6): 479-532, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37787157

RESUMO

In the last decade and a half, advances in genetic sequencing technologies have revolutionized systematics, transforming the field from studying morphological characters or a few genetic markers, to genomic datasets in the phylogenomic era. A plethora of molecular phylogenetic studies on many taxonomic groups have come about, converging on, or refuting prevailing morphology or legacy-marker-based hypotheses about evolutionary affinities. Spider systematics has been no exception to this transformation and the inter-relationships of several groups have now been studied using genomic data. About 51 500 extant spider species have been described, all with a conservative body plan, but innumerable morphological and behavioural peculiarities. Inferring the spider tree of life using morphological data has been a challenging task. Molecular data have corroborated many hypotheses of higher-level relationships, but also resulted in new groups that refute previous hypotheses. In this review, we discuss recent advances in the reconstruction of the spider tree of life and highlight areas where additional effort is needed with potential solutions. We base this review on the most comprehensive spider phylogeny to date, representing 131 of the 132 spider families. To achieve this sampling, we combined six Sanger-based markers with newly generated and publicly available genome-scale datasets. We find that some inferred relationships between major lineages of spiders (such as Austrochiloidea, Palpimanoidea and Synspermiata) are robust across different classes of data. However, several new hypotheses have emerged with different classes of molecular data. We identify and discuss the robust and controversial hypotheses and compile this blueprint to design future studies targeting systematic revisions of these problematic groups. We offer an evolutionary framework to explore comparative questions such as evolution of venoms, silk, webs, morphological traits and reproductive strategies.


Assuntos
Aranhas , Humanos , Animais , Aranhas/genética , Filogenia , Genômica , Análise de Sequência de DNA , Genoma
4.
iScience ; 26(9): 107684, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37694155

RESUMO

Advanced sequencing technologies have expedited resolution of higher-level arthropod relationships. Yet, dark branches persist, principally among groups occurring in cryptic habitats. Among chelicerates, Solifugae ("camel spiders") is the last order lacking a higher-level phylogeny and have thus been historically characterized as "neglected [arachnid] cousins". Though renowned for aggression, remarkable running speed, and xeric adaptation, inferring solifuge relationships has been hindered by inaccessibility of diagnostic morphological characters, whereas molecular investigations have been limited to one of 12 recognized families. Our phylogenomic dataset via capture of ultraconserved elements sampling all extant families recovered a well-resolved phylogeny, with two distinct groups of New World taxa nested within a broader Paleotropical radiation. Divergence times using fossil calibrations inferred that Solifugae radiated by the Permian, and most families diverged prior to the Paleogene-Cretaceous extinction, likely driven by continental breakup. We establish Boreosolifugae new suborder uniting five Laurasian families, and Australosolifugae new suborder uniting seven Gondwanan families using morphological and biogeographic signal.

5.
Mol Phylogenet Evol ; 186: 107855, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37311493

RESUMO

The miniature orb weaving spiders (symphytognathoids) are a group of small spiders (<2 mm), including the smallest adult spider Patu digua (0.37 mm in body length), that have been classified into five families. The species of one of its constituent lineages, the family Anapidae, build a remarkable diversity of webs (ranging from orbs to sheet webs and irregular tangles) and even include a webless kleptoparasitic species. Anapids are also exceptional because of the extraordinary diversity of their respiratory systems. The phylogenetic relationships of symphytognathoid families have been recalcitrant with different classes of data, such as, monophyletic with morphology and its concatenation with Sanger-based six markers, paraphyletic (including a paraphyletic Anapidae) with solely Sanger-based six markers, and polyphyletic with transcriptomes. In this study, we capitalized on a large taxonomic sampling of symphytognathoids, focusing on Anapidae, and using de novo sequenced ultraconserved elements (UCEs) combined with UCEs recovered from available transcriptomes and genomes. We evaluated the conflicting relationships using a variety of support metrics and topology tests. We found support for the phylogenetic hypothesis proposed using morphology to obtain the "symphytognathoids'' clade, Anterior Tracheal System (ANTS) Clade and monophyly of the family Anapidae. Anapidae can be divided into three major lineages, the Vichitra Clade (including Teutoniella, Holarchaea, Sofanapis and Acrobleps), the subfamily Micropholcommatinae and the Orb-weaving anapids (Owa) Clade. Biogeographic analyses reconstructed a hypothesis of multiple long-distance transoceanic dispersal events, potentially influenced by the Antarctic Circumpolar Current and West Wind Drift. In symphytognathoids, the ancestral anterior tracheal system transformed to book lungs four times and reduced book lungs five times. The posterior tracheal system was lost six times. The orb web structure was lost four times independently and transformed into sheet web once.


Assuntos
Aranhas , Animais , Filogenia , Genoma , Transcriptoma , Sistema Respiratório
6.
Zootaxa ; 5380(1): 77-95, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38220789

RESUMO

The taxonomy of the genus Spariolenus Simon, 1880 (Heteropodinae) is updated in its entire distribution range in South and West Asia. Newly collected specimens and historical museum material were studied, some date back to more than 124 years. Four new species are described as Spariolenus omidvarbrothers sp. n. (male, female) from southeastern Iran, S. baluchistanicus sp. n. (female) from Pakistan and, S. bakasura sp. n. (male, female) and S. kabandha sp. n. (female) from the Western Ghats and northern regions of India, respectively; specimens of the latter three species had been previously incorrectly identified as S. tigris Simon, 1880. Spariolenus lindbergi (Roewer, 1962) comb. nov. is transferred from the genus Heteropoda Latreille, 1804. We discovered and described its male for the first time, along with redescription of the female using recently collected material near the type locality from Afghanistan. Two species, Spariolenus mansourii Moradmand, 2017 (Iran) and S. secundus Jger, 2006 (Oman) are recorded from new geographic localities. A distribution map of all extant Spariolenus species with updated records is presented.


Assuntos
Aranhas , Feminino , Masculino , Animais , Distribuição Animal
7.
J Ayurveda Integr Med ; 13(1): 100496, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34334979

RESUMO

Covid 19 pandemic has placed challenges in front of medical health fraternity in terms of management, prevention and immunity building. Effectiveness of any medication has not conclusively proven; hence there is need for integrative management of Covid 19. We have managed a critical case of Covid-19 having history of thalassemia, hypothyroidism with integrative management of Ayurveda and modern medicine. A male patient (59 years of age) with history of thalassemia had complaints of cough and breathlessness since 4 days. He performed RT PCR because of his exposure to a Covid positive cases in immediate family. He was treated with Favipiravir at home for 5 days. He deteriorated on 6th day with SPO2 dropped to 75%, temp raised to 101 F and respiratory rate (RR) raised to 45/min. He was admitted in Yogeshwari Hospital Daund, Maharashtra; treated with oxygen inhalation, Remdesvir and Ayurveda medicines in intensive care unit (ICU). Ayurveda treatment protocol was advised through telemedicine. Significant improvement in clinical symptoms and normal HRCT was observed at completion of treatment. This case report provides further directions for integrative management in cases of Covid 19. Further clinical research studies in this direction are warranted.

8.
Zootaxa ; 5026(1): 71-101, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34810940

RESUMO

We address the phylogenetic relationships of pimoid spiders (Pimoidae) using a standard target-gene approach with an extensive taxonomic sample, which includes representatives of the four currently recognized pimoid genera, 26 linyphiid genera, a sample of Physoglenidae, Cyatholipidae and one Tetragnathidae species. We test the monophyly of Pimoidae and Linyphiidae and explore the biogeographic history of the group. Nanoa Hormiga, Buckle and Scharff, 2005 and Pimoa Chamberlin Ivie, 1943 form a clade which is the sister group of a lineage that includes all Linyphiidae, Weintrauboa Hormiga, 2003 and Putaoa Hormiga and Tu, 2008. Weintrauboa, Putaoa, Pecado and Stemonyphantes form a clade (Stemonyphantinae) sister to all remaining linyphiids. We use the resulting optimal molecular phylogenetic tree to assess hypotheses on the male palp sclerite homologies of pimoids and linyphiids. Pimoidae is redelimited to only include Pimoa and Nanoa. We formalize the transfer from Pimoidae of the genera Weintrauboa and Putaoa to Linyphiidae, re-circumscribe the linyphiid subfamily Stemonyphantinae, and offer revised morphological diagnoses for Pimoidae and Linyphiidae.


Assuntos
Aranhas , Animais , Masculino , Filogenia , Aranhas/genética
9.
Cladistics ; 37(3): 298-316, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34478199

RESUMO

High throughput sequencing and phylogenomic analyses focusing on relationships among spiders have both reinforced and upturned long-standing hypotheses. Likewise, the evolution of spider webs-perhaps their most emblematic attribute-is being understood in new ways. With a matrix including 272 spider species and close arachnid relatives, we analyze and evaluate the relationships among these lineages using a variety of orthology assessment methods, occupancy thresholds, tree inference methods and support metrics. Our analyses include families not previously sampled in transcriptomic analyses, such as Symphytognathidae, the only araneoid family absent in such prior works. We find support for the major established spider lineages, including Mygalomorphae, Araneomorphae, Synspermiata, Palpimanoidea, Araneoidea and the Retrolateral Tibial Apophysis Clade, as well as the uloborids, deinopids, oecobiids and hersiliids Grade. Resulting trees are evaluated using bootstrapping, Shimodaira-Hasegawa approximate likelihood ratio test, local posterior probabilities and concordance factors. Using structured Markov models to assess the evolution of spider webs while accounting for hierarchically nested traits, we find multiple convergent occurrences of the orb web across the spider tree-of-life. Overall, we provide the most comprehensive spider tree-of-life to date using transcriptomic data and use new methods to explore controversial issues of web evolution, including the origins and multiple losses of the orb web.


Assuntos
Evolução Biológica , Proteínas de Insetos/genética , Filogenia , Comportamento Predatório/fisiologia , Aranhas/classificação , Transcriptoma , Animais , Aranhas/genética , Aranhas/fisiologia
10.
Mol Biol Evol ; 38(3): 891-903, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32986823

RESUMO

Genome-scale data sets are converging on robust, stable phylogenetic hypotheses for many lineages; however, some nodes have shown disagreement across classes of data. We use spiders (Araneae) as a system to identify the causes of incongruence in phylogenetic signal between three classes of data: exons (as in phylotranscriptomics), noncoding regions (included in ultraconserved elements [UCE] analyses), and a combination of both (as in UCE analyses). Gene orthologs, coded as amino acids and nucleotides (with and without third codon positions), were generated by querying published transcriptomes for UCEs, recovering 1,931 UCE loci (codingUCEs). We expected that congeners represented in the codingUCE and UCEs data would form clades in the presence of phylogenetic signal. Noncoding regions derived from UCE sequences were recovered to test the stability of relationships. Phylogenetic relationships resulting from all analyses were largely congruent. All nucleotide data sets from transcriptomes, UCEs, or a combination of both recovered similar topologies in contrast with results from transcriptomes analyzed as amino acids. Most relationships inferred from low-occupancy data sets, containing several hundreds of loci, were congruent across Araneae, as opposed to high occupancy data matrices with fewer loci, which showed more variation. Furthermore, we found that low-occupancy data sets analyzed as nucleotides (as is typical of UCE data sets) can result in more congruent relationships than high occupancy data sets analyzed as amino acids (as in phylotranscriptomics). Thus, omitting data, through amino acid translation or via retention of only high occupancy loci, may have a deleterious effect in phylogenetic reconstruction.


Assuntos
Filogenia , Aranhas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases
11.
Mol Ecol Resour ; 20(1): 185-203, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31599100

RESUMO

Phylogenomic methods have proven useful for resolving deep nodes and recalcitrant groups in the spider tree of life. Across arachnids, transcriptomic approaches may generate thousands of loci, and target-capture methods, using the previously designed arachnid-specific probe set, can target a maximum of about 1,000 loci. Here, we develop a specialized target-capture probe set for spiders that contains over 2,000 ultraconserved elements (UCEs) and then demonstrate the utility of this probe set through sequencing and phylogenetic analysis. We designed the 'spider-specific' probe set using three spider genomes (Loxosceles, Parasteatoda and Stegodyphus) and ensured that the newly designed probe set includes UCEs from the previously designed Arachnida probe set. The new 'spider-specific' probes were used to sequence UCE loci in 51 specimens. The remaining samples included five spider genomes and taxa that were enriched using Arachnida probe set. The 'spider-specific' probes were also used to gather loci from a total of 84 representative taxa across Araneae. On mapping these 84 taxa to the Arachnida probe set, we captured at most 710 UCE loci, while the spider-specific probe set captured up to 1,547 UCE loci from the same taxon sample. Phylogenetic analyses using maximum likelihood and coalescent methods corroborate most nodes resolved by recent transcriptomic analyses, but not all (e.g. UCE data suggest monophyly of 'symphytognathoids'). Our preferred hypothesis based on topology tests, suggests monophyly of the 'symphytognathoids' (the miniature orb weavers), which in previous studies has only been supported by a combination of morphological and behavioural characters.


Assuntos
Evolução Molecular , Aranhas/genética , Animais , Aracnídeos/genética , Sequência Conservada , Genoma , Filogenia , Especificidade da Espécie , Aranhas/classificação
12.
Zootaxa ; 4524(2): 237-244, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30486124

RESUMO

A new thread-legged assassin bug species, Myiophanes (Myiophanes) wygodzinskyi sp. nov. (Hemiptera: Heteroptera: Reduviidae: Emesinae: Emesini), collected from Ravana Cave in Uva Province of Sri Lanka, is described. It is the largest species of the genus described so far.


Assuntos
Cavernas , Reduviidae , Distribuição Animal , Animais , Heterópteros , Sri Lanka , Triatoma
13.
R Soc Open Sci ; 5(6): 180211, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30110422

RESUMO

Batrachochytrium dendrobatidis (Bd) is a pathogen killing amphibians worldwide. Its impact across much of Asia is poorly characterized. This study systematically surveyed amphibians for Bd across rocky plateaus in the northern section of the Western Ghats biodiversity hotspot, India, including the first surveys of the plateaus in the coastal region. These ecosystems offer an epidemiological model system since they are characterized by differing levels of connectivity, edaphic and climatic conditions, and anthropogenic stressors. One hundred and eighteen individuals of 21 species of Anura and Apoda on 13 plateaus ranging from 67 to 1179 m above sea level and 15.89 to 17.92° North latitude were sampled. Using qPCR protocols, 79% of species and 27% of individuals tested were positive for Bd. This is the first record of Bd in caecilians in India, the Critically Endangered Xanthophryne tigerina and Endangered Fejervarya cf. sahyadris. Mean site prevalence was 28.15%. Prevalence below the escarpment was 31.2% and 25.4% above. The intensity of infection (GE) showed the reverse pattern. Infection may be related to elevational temperature changes, thermal exclusion, inter-site connectivity and anthropogenic disturbance. Coastal plateaus may be thermal refuges from Bd. Infected amphibians represented a wide range of ecological traits posing interesting questions about transmission routes.

14.
PLoS One ; 13(3): e0194810, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29579111

RESUMO

The importance of patch quality for amphibians is frequently overlooked in distribution models. Here we demonstrate that it is highly important for the persistence of endemic and endangered amphibians found in the threatened and fragile ecosystems that are the rocky plateaus in Western Maharashtra, India. These plateaus are ferricretes of laterite and characterise the northern section of the Western Ghats/Sri Lanka Biodiversity Hotspot, the eighth most important global hotspot and one of the three most threatened by population growth. We present statistically supported habitat associations for endangered and data-deficient Indian amphibians, demonstrating significant relationships between individual species and their microhabitats. Data were collected during early monsoon across two seasons. Twenty-one amphibian taxa were identified from 14 lateritic plateaus between 67 and 1179m above sea level. Twelve of the study taxa had significant associations with microhabitats using a stepwise analysis of the AICc subroutine (distLM, Primer-e, v7). Generalist taxa were associated with increased numbers of microhabitat types. Non-significant associations are reported for the remaining 9 taxa. Microhabitat distribution was spatially structured and driven by climate and human activity. Woody plants were associated with 44% of high-elevation taxa. Of the 8 low-elevation taxa 63% related to water bodies and 60% of those were associated with pools. Rock size and abundance were important for 33% of high elevation specialists. Three of the 4 caecilians were associated with rocks in addition to soil and stream presence. We conclude the plateaus are individualistic patches whose habitat quality is defined by their microhabitats within climatic zones.


Assuntos
Anfíbios/fisiologia , Ecossistema , Animais , Biodiversidade , Mudança Climática , Índia , Estações do Ano
15.
Zootaxa ; 4127(2): 365-75, 2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-27395629

RESUMO

A new cavernicolous, thread-legged assassin bug, Bagauda ernstmayri sp. nov. (Hemiptera: Heteroptera: Reduviidae: Emesinae), collected from a cave near Satara, in the Western Ghats of Maharashtra, India, is described. Its interaction with the web of an uloborid spider Zosis geniculata (Olivier, 1789) (Araneae: Uloboridae) is discussed.


Assuntos
Triatoma/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Índia , Masculino , Tamanho do Órgão , Triatoma/anatomia & histologia , Triatoma/crescimento & desenvolvimento
20.
Biodivers Data J ; (4): e7949, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099559

RESUMO

BACKGROUND: While surveying bugs and spiders in the caves of Satara District, Maharashtra, one of us (SK) collected a thread-legged bug associated with a spider web. NEW INFORMATION: A Sri Lankan Emesinae bug, Myiophanes greeni Distant (Heteroptera: Reduviidae: Emesinae) is reported for the first time from India. The species is redescribed with several illustrations including male genitalia.

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