Novinky v taxonomii a vo svete vtackarov

Diskusia viazaná na konkrétne druhy vtáčkarov

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 13. Augusta 2019, 20:28

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 Fernando Pérez-Miles, Ray Gabriel, and Danniella Sherwood "Neischnocolus Petrunkevitch, 1925, senior synonym of Ami Pérez-Miles, 2008 and Barropelma Chamberlin, 1940 (Araneae: Theraphosidae)," Arachnology 18(2), 150-155, (5 August 2019). https://doi.org/10.13156/arac.2018.18.2.150

The recent rediscovery and examination of the holotype of Neischnocolus panamanus Petrunkevitch, 1925 and its comparison with type material of the genera Barropelma Chamberlin, 1940 and Ami Pérez-Miles, 2008 led us to establish their generic synonymy. Ami species and the monotypic Barropelma parvior (Chamberlin & Ivie, 1936) fit with the diagnostic characters of Neischnocolus, with the presence of modified type I urticating setae and the singular spermathecal morphology. B. parvior is considered a junior synonym of N. panamanus syn. nov. based on genital organ morphology and geographical location. Ami bladesi Pérez- Miles, Gabriel & Gallon, 2008 is also considered a junior synonym of Neischnocolus panamanus syn nov. based on genital organ morphology and geographical location. As a consequence, of the synonymies of the genera Barropelma and Ami with Neischnocolus, seven new combinations are created: N. amazonica comb. nov., N. armihuarensis comb. nov., N. caxiuana comb. nov., N. obscurus comb. nov., N. pijaos comb. nov., N. weinmanni comb. nov. and N. yupanquii comb. nov.
Cely rod Ami sa premenoval a presunul do rodu Neischnocolus s novym typovym druhom Neischnocolus panamanus.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 18. Októbra 2019, 18:15

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Nanayakkara, R. P., Sumanapala, A. P. & Kirk, P. (2019). Another from Sri Lanka, after 126 years; Chilobrachys jonitriantisvansicklei sp. nov. (Araneae: Theraphosidae) from a fragmented forest patch in the wet zone of Sri Lanka. Journal of the British Tarantula Society 34(2): 25-36. 
The new species of Chilobrachys was collectedfrom a fragmented rainforest patch, 347hectares in extent, located in the KalutaraDistrict, Western Province of Sri Lanka. Thespecimens were collected from burrows on asoil embankment covered with bryophytes,along the road, with a clear tubular extensionmade up of soil and other debris. Interestingly,the majority of the known members of thegenus Chilobrachys are shades of brown, black orgrey, and lack vibrant colours or iridescentsheens on their dorsal surface. The collectedspecimen on the other hand has a metallicturquoise-blue sheen on all four legs and alsoan iridescent sheen on the carapace andabdomen. As such, the collected specimen,differs greatly from the other members of thegenus, including C. nitelinus, thereby warrantingits taxonomy description as a new species. Thediscovery was part of an ongoing, island-widestudy on the mygalomorph spiders in Sri Lanka.Here we describe the second species ofChilobrachys from Sri Lanka after 126 years.
Popisany Chilobrachys jonitriantisvansicklei.

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Longhorn, S. J. & Gabriel, R. (2019). Revised taxonomic status of some Mexican and Central American tarantulas (Araneae: Theraphosidae), with transfers from Aphonopelma Pocock, 1901, and a new genus from the Pacific lowlands of Nicaragua and Costa Rica. Arachnology 18(2): 101-120. doi:10.13156/arac.2018.18.2.101
The type material of several Central American tarantulas (Theraphosidae; Theraphosinae) were re-examined within a broader revision involving the defunct genus Eurypelma Koch, 1850 and the poorly defined Aphonopelma Pocock, 1901. Here, we create the new monotypic genus Sandinista gen. nov. for a revised taxon Sandinista lanceolatum (Simon, 1891) comb. nov., which is a small tarantula from the Pacific lowland dry forests of Nicaragua and Costa Rica. It was originally described under Eurypelma and later transferred to Aphonopelma without justification. Based on comparison of type specimens against new material, we emphasise its unusual bulb anatomy to rediagnose it as a new genus with suggested close affinity to Aphonopelma Pocock, 1901 (sensu stricto), Sphaerobothria Karsch, 1897, and Stichoplastoris Rudloff, 1997. We also re-examined the type material of Brachypelma fossorium Valerio, 1980, which is here treated as a junior synonym of S. lanceolatum, syn. nov. We also discuss the Mexican/Central American genus Crassicrus Reichling & West, 1999, into which we transfer another former Eurypelma from the Yucatán. This species was later called Aphonopelma stoicum (Chamberlin, 1925), which we revise as Crassicrus stoicum comb. nov. and contrast against other described congeners. We also re-evaluate two other specimens later determined as Aphonopelma stoicum by Schmidt & Piepho (1997), including the alleged first female for the species, and consider them as mis-identified congeners. Finally, we provide some discussion on Citharacanthus meermani Reichling & West, 2000 from Belize in the context of Crassicrus, due to similar aspects of their male palpal bulb morphology, highlighting potentially informative aspects.
-vznikol rod Sandinista s jedinym druhom Sandinista lanceolatum(ex Brachypelma fossoria, Eurypelma lanceolatum)
-Crassicrus stoicum (ex Aphonopelma stoicum)

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 23. Októbra 2019, 21:47

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Gabriel, R. & Sherwood, D. (2019c). The revised taxonomic placement of some arboreal Ornithoctoninae Pocock, 1895 with description of a new species of Omothymus Thorell, 1891 (Araneae: Theraphosidae). Arachnology 18(2): 137-147.
Abstract
The chaotic taxonomy of the subfamily OrnithoctoninaePocock, 1895 is partially addressed, with a focus on redefiningthe arboreal genera Lampropelma Simon, 1892, OmothymusThorell, 1891, and Phormingochilus Pocock, 1895. Previousworks placing heavy emphasis on unstable taxonomic charactersare addressed and stable taxonomic features presented for theclear delineation of males of arboreal ornithoctonine genera.The male of Phormingochilus everetti Pocock, 1895 is described for the first time. A new species, Omothymus rafni sp. nov.is described from historical material collected in Sumatra.Lampropelma violaceopes Abraham, 1924 is transferred to Omothymus based on comparative leg measurements andgeographical location comb. nov. Lampropelma nigerrimumarboricola Schmidt & Barensteiner, 2015 is transferred to thegenus Phormingochilus with full species status acknowledged,giving the new combination Phormingochilus arboricolacomb. nov. Omothymus thorelli Simon, 1901 is considereda junior synonym of Omothymus schioedtei Thorell, 1891syn. nov., based on similar morphology and geographicallocations. Phormingochilus carpenteri Smith & Jacobi, 2015is transferred to the genus Lampropelma based on comparativeleg measurements and geographical location comb. nov.Phormingochilus kirki Smith & Jacobi, 2015 is considered ajunior synonym of L. carpenteri syn. nov. Phormingochilus fuchsi Strand, 1906 is transferred to the genus Omothymus basedon comparative leg measurement and geographic distributioncomb. nov. Phormingochilus tigrinus Pocock, 1895 is removedfrom synonymy with P. everetti based on the lack of justificationfor the synonymy comb. rest. Omothymus dromeus Chamberlin,1917 is removed from Omothymus and returned to the restoredgenus Melognathus comb. rest.
-prvy opis samca Phormingochilus everetti
-novy druh Omothymus rafni
-Lampropelma violaceopes sa presunula do rodu Omothymus
-Lampropelma nigerrimumarboricola sa presunula do rodu Phormingochilus
-Phormingochilus carpenteri sa presunul do rodu Lampropelma a Phormingochilus kirki je povazovane za mladsie synonymum L. carpenteri (oba sa presunuli pod nazov Lampropelma carpenteri)
-Phormingochilus fuchsi je presunuty do rodu Omothymus
-Phormingochilus tigrinus sa uz nepovazuje za synonymum pre P. everetti
-Omothymus dromeus je opatovne vrateny do rodu Melognathus

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 23. Októbra 2019, 21:52

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Foley, S., Lüddecke, T., Chen, D. Q., Krehenwinkel, H., Künzel, S., Longhorn, S., Wendt, I., Wirth, V. von, Tänzler, R., Vences, M. & Piel, W. H. (2019). Tarantula phylogenomics: A robust phylogeny of deep theraphosid clades inferred from transcriptome data sheds light on the prickly issue of urticating setae evolution. Molecular Phylogenetics and Evolution 140(106573): 1-12. 
Mygalomorph spiders of the family Theraphosidae, known to the broader public as tarantulas, are among the most recognizable arachnids on earth due to their large size and widespread distribution. Their use of urticating setae is a notable adaptation that has evolved exclusively in certain New World theraphosids. Thus far, the evolutionary history of Theraphosidae remains poorly understood; theraphosid systematics still largely relies on morphological datasets, which suffer from high degrees of homoplasy, and traditional Sanger sequencing of preselected genes failed to provide strong support for supra-generic clades. In this study, we provide the first robust phylogenetic hypothesis of theraphosid evolution inferred from transcriptome data. A core ortholog approach was used to generate a phylogeny from 2460 orthologous genes across 25 theraphosid genera, representing all of the major theraphosid subfamilies, except Selenogyrinae. Our phylogeny recovers an unprecedented monophyletic group that comprises the vast majority of New World theraphosid subfamilies including Aviculariinae, Schismatothelinae and Theraphosinae. Concurrently, we provide additional evidence for the integrity of questionable subfamilies, such as Poecilotheriinae and Psalmopoeinae, and support the non-monophyly of Ischnocolinae. The deeper relationships between almost all subfamilies are confidently inferred. We also used our phylogeny in tandem with published morphological data to perform ancestral state analyses on urticating setae, and contextualize our reconstructions with emphasis on the complex evolutionary history of the trait.

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Nentwig, W., Blick, T., Gloor, D., Jäger, P. & Kropf, C. (2019). Tackling taxonomic redundancy in spiders: the infraspecific spider taxa described by Embrik Strand (Arachnida: Araneae). Arachnologische Mitteilungen 58: 29-51.
Heteroscodra crassipes latithorax Strand, 1920 = Heteroscodra crassipes Hirst, 1907
Hysterocrates affinis angusticeps - Nomen dubium
Hysterocrates robustus sulcifera - (subspecies inquirenda)
Pseudhapalopus trinitatis pauciaculeis - (subspecies inquirenda)

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 7. Novembra 2019, 18:44

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Mendoza, Jorge; Francke, Oscar (November 2019). "Systematic revision of Mexican threatened tarantulas Brachypelma (Araneae: Theraphosidae: Theraphosinae), with a description of a new genus, and implications on the conservation". Zoological Journal of the Linnean Society.
The tarantula genus Brachypelma includes colourful species that are highly sought after in the commercial pet trade. They are all included in CITES appendix II. We present phylogenetic analyses using molecular and morphological characters to revise Brachypelma, in which we include all currently known species. Our results agree with a previous study that shows the non-monophyly of Brachypelma. Both phylogenies strongly favour the division of Brachypelma into two smaller genera. The first clade (Brachypelma s.s.) is formed by B.albiceps, B. auratum, B. baumgarteni, B. boehmei, B. emilia, B. hamorii, B. klaasi and B. smithi. The species included in the second clade are transferred to the new genus Tliltocatl and is formed by T. albopilosum comb. nov., T. epicureanum comb. nov., T. kahlenbergi comb. nov., T. sabulosum comb. nov., T. schroederi comb. nov., T. vagans comb. nov. and T. verdezi comb. nov. Both genera can be differentiated by their coloration and the shape of the genitalia. We transfer to Tliltocatl: T. alvarezi, T. andrewi and T. aureoceps, but should be considered as nomina dubia. In addition, we transfer B. fossorium to Stichoplastoris. We discuss the implications of these taxonomical changes for CITES and for the Mexican Laws for wildlife protection.
Celkom zasadne asak nie neocavane, rod Brachypelma sa rozdelil na dve samostatne rody Brachypelma a Tliltocatl.

B.albiceps, B. auratum, B. baumgarteni, B. boehmei, B. emilia, B. hamorii, B. klaasi a B. smithi

T. albopilosum, T. epicureanum, T. kahlenbergi, T. sabulosum, T. schroederi, T. vagans,T. verdezi (tvz. "vagans group")

Do rodu Tliltocatl boli presunute aj T. alvarezi, T. andrewi a T. aureoceps tie vsak povazuju za nomina dubia.

B. fossorium bola presunuta do rodu Stichoplastoris.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 10. Novembra 2019, 14:31

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Kaderka, Radan & Bulantová, Jana & Heneberg, Petr & Rezác, Milan. (2019). Urticating setae of tarantulas (Araneae: Theraphosidae): morphology, revision of typology and terminology and implications for taxonomy. 
V priprave...
Tarantula urticating setae are modified setae located on the abdomen or pedipalps, which represent an effective defensive mechanism against vertebrate or invertebrate predators and intruders. They are also useful taxonomic tools as morphological characters facilitating the classification of New World theraphosid spiders. In the present study, the morphology of urticating setae was studied on 144 taxa of New World theraphosids, including ontogenetic stages in chosen species, except for species with urticating setae of type VII. The typology of urticating setae was revised, and types I, III and IV were redescribed. The urticating setae in spiders with type I setae, which were originally among type III or were considered setae of intermediate morphology between types I and III, are newly considered to be ontogenetic derivatives of type I and are described as subtypes. Setae of intermediate morphology between that of body setae and type II urticating setae that were found in Iridopelma hirsutum Pocock, 1901 and Antillena rickwesti (Bertani & Huff, 2013) may provide another evidence that type II urticating setae evolved from body setae. It is supposed that the fusion of barbs with the shaft may lead to the morphology of type II setae. As the type II setae of Aviculariinae evolved independently to the UrS of Theraphosinae and both subfamilies represent two non-sister groups, this should explain the differences in the morphology of body setae in Aviculariinae and Theraphosinae. The terminology of “barbs” and “reversed barbs” was revised and redefined, newly emphasizing the real direction of barbs.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 14. Decembra 2019, 20:16

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Ríos Tamayo, Duniesky. (2019). Three new species of Euathlus Ausserer, 1875 (Araneae, Theraphosidae) from Argentina. Studies on Neotropical Fauna and Environment. 1-13. 10.1080/01650521.2019.1696653. 
Euathlus Ausserer, 1875 is a South American genus of spiders of the family Theraphosidae known from Chile and Argentina. Three new species from Argentina: Euathlus mauryi sp. n. (from San Juan province), Euathlus grismadoi sp. n. (from La Rioja province), and Euathlus pampa sp. n. (from Salta province) are described here. New records of the previous species Euathlus diamante and Euathlus tenebrarum are contributed. The distribution of these new species expands the geographical distribution of the genus along the Andean hills, with Salta province as the northernmost record of the genus. A key is provided for identification of Euathlus species as well as a map with all the records in Argentina.
Opisane nove tri druhy v rode Euathlus - mauryi, grismadoi, pampa.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 8. Februára 2020, 13:08

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Deng Z, Wang Y, Shi W, et al. Haplopelma hainanum venom induces inflammatory skin lesions. PeerJ. 2020;8:e8264. Published 2020 Jan 10. doi:10.7717/peerj.8264
The Haplopelma hainanum is a species of theraphosid spider from China. Its large size and charming appearance make this species a popular pet. According to a previous study, theraphosid spider bites can induce pain, erythema, and edema in humans and can present more severely in domestic animals. The pathological consequences of envenomation by H. hainanum remain unclear. In this study, we investigated the effects and mechanisms of H. hainanum envenomation in mice. We showed that the venom induced slight swelling, intense inflammatory response, and increased the microvascular density in mice skin. Moreover, we found that 50 µg/ml of the spider’s venom induced IL-1β expression in both HaCaT cells and fibroblast cells, but repressed CXCL10 expression in fibroblasts. The venom significantly induced cell senescence and repressed cell proliferation and migration in both HaCaT cells and fibroblast cells. Finally, we examined the expression of Nav channel in HaCaT and fibroblast cells and found that H. hainanum venom effectively inhibited Na+ currents in HaCaT cells. Our study calls for further investigation of the pathological consequences and potential mechanisms of H. hainanum envenomation. This information might assist in the development of suitable therapy.

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Silva-Pereyra V, Fábrica CG, Biancardi CM, Pérez-Miles F. Kinematics of male Eupalaestrus weijenberghi (Araneae, Theraphosidae) locomotion on different substrates and inclines. PeerJ. 2019;7:e7748. Published 2019 Sep 26. doi:10.7717/peerj.7748
Background The mechanics and energetics of spider locomotion have not been deeply investigated, despite their importance in the life of a spider. For example, the reproductive success of males of several species is dependent upon their ability to move from one area to another. The aim of this work was to describe gait patterns and analyze the gait parameters of Eupalaestrus weijenberghi (Araneae, Theraphosidae) in order to investigate the mechanics of their locomotion and the mechanisms by which they conserve energy while traversing different inclinations and surfaces. Methods Tarantulas were collected and marked for kinematic analysis. Free displacements, both level and on an incline, were recorded using glass and Teflon as experimental surfaces. Body segments of the experimental animals were measured, weighed, and their center of mass was experimentally determined. Through reconstruction of the trajectories of the body segments, we were able to estimate their internal and external mechanical work and analyze their gait patterns. Results Spiders mainly employed a walk-trot gait. Significant differences between the first two pairs and the second two pairs were detected. No significant differences were detected regarding the different planes or surfaces with respect to duty factor, time lags, stride frequency, and stride length. However, postural changes were observed on slippery surfaces. The mechanical work required for traversing a level plane was lower than expected. In all conditions, the external work, and within it the vertical work, accounted for almost all of the total mechanical work. The internal work was extremely low and did not rise as the gradient increased. Discussion Our results support the idea of considering the eight limbs functionally divided into two quadrupeds in series. The anterior was composed of the first two pairs of limbs, which have an explorative and steering purpose and the posterior was more involved in supporting the weight of the body. The mechanical work to move one unit of mass a unit distance is almost constant among the different species tested. However, spiders showed lower values than expected. Minimizing the mechanical work could help to limit metabolic energy expenditure that, in small animals, is relatively very high. However, energy recovery due to inverted pendulum mechanics only accounts for only a small fraction of the energy saved. Adhesive setae present in the tarsal, scopulae, and claw tufts could contribute in different ways during different moments of the step cycle, compensating for part of the energetic cost on gradients which could also help to maintain constant gait parameters.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 8. Februára 2020, 13:16

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Fukushima C, Mendoza JI, West RC, et al. Species conservation profiles of tarantula spiders (Araneae, Theraphosidae) listed on CITES. Biodivers Data J. 2019;7:e39342. Published 2019 Nov 8. doi:10.3897/BDJ.7.e39342
CITES is an international agreement between governments to ensure that international trade in specimens of wild animals and plants does not threaten their survival. Regarding spiders, all species listed in CITES are tarantulas. They are included in Appendix II, meaning that they are species that are not necessarily now threatened with extinction but that they may become so unless trade is closely controlled. Many tarantulas are legally and illegally traded in the pet market and they are one of the most traded invertebrate groups. Originally, the CITES list published in 1995 included all the current species of the genus Brachypelma Simon, 1891 plus Aphonopelma pallidum (F. O. Pickard-Cambridge, 1897) and the so-called Aphonopelma albiceps (Pocock, 1903). After that, some taxonomic changes were done, as well as descriptions of new species in the genus Brachypelma. The objective of this paper is to assess the 21 taxonomically valid spider species listed on CITES according to the IUCN criteria, study the general patterns and trends and advise on possible future conservation actions critical for the survival of endangered species.

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Aguilera MA, Montenegro V R, Casanueva ME. Impact of disturbed areas on Theraphosidae spiders diversity (Araneae) and first population data of Grammostola rosea (Walckenaer) in Panul Park. Ecol Evol. 2019;9(10):5802–5809. Published 2019 May 8. doi:10.1002/ece3.5163
Soil fauna constitutes one of the most abundant and richest environments on earth (Coleman et al. 2004, Fundamentals of solil ecology, 2nd ed. Elsevier Academic Press, London, UK). Different degrees of soil disturbance can affect arthropod diversity, which allows a correlation of biodiversity to quality of habitat. The present study aimed to evaluate the impact of habitat on Theraphosidae spiders, with special focus on Grammostola rosea. Slight differences in the diversity of Theraphosidae between the disturbed area of Cerro Huechuraba and the undisturbed Panul Park were found. However, a high dominance of G. rosea was observed in both study areas. G. rosea density 1,350 ind/ha in Panul Park, and 750 ind/ha in Cerro Huechuraba. UPGMA cluster analysis did not show significant differences between established environments. A standard methodology to develop inventories of Theraphosidae was proposed. The distribution of G. rosea and its natural history were reported.

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Machałowski T, Wysokowski M, Tsurkan MV, et al. Spider Chitin: An Ultrafast Microwave-Assisted Method for Chitin Isolation from Caribena versicolor Spider Molt Cuticle. Molecules. 2019;24(20):3736. Published 2019 Oct 16. doi:10.3390/molecules24203736
Chitin, as a fundamental polysaccharide in invertebrate skeletons, continues to be actively investigated, especially with respect to new sources and the development of effective methods for its extraction. Recent attention has been focused on marine crustaceans and sponges; however, the potential of spiders (order Araneae) as an alternative source of tubular chitin has been overlooked. In this work, we focused our attention on chitin from up to 12 cm-large Theraphosidae spiders, popularly known as tarantulas or bird-eating spiders. These organisms “lose” large quantities of cuticles during their molting cycle. Here, we present for the first time a highly effective method for the isolation of chitin from Caribena versicolor spider molt cuticle, as well as its identification and characterization using modern analytical methods. We suggest that the tube-like molt cuticle of this spider can serve as a naturally prefabricated and renewable source of tubular chitin with high potential for application in technology and biomedicine.

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Re: Novinky v taxonomii a vo svete vtackarov

Príspevok od užívateľa Sceptic » 8. Februára 2020, 13:24

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Lüddecke T, Vilcinskas A, Lemke S. Phylogeny-Guided Selection of Priority Groups for Venom Bioprospecting: Harvesting Toxin Sequences in Tarantulas as a Case Study. Toxins (Basel). 2019;11(9):488. Published 2019 Aug 25. doi:10.3390/toxins11090488
Animal venoms are promising sources of novel drug leads, but their translational potential is hampered by the low success rate of earlier biodiscovery programs, in part reflecting the narrow selection of targets for investigation. To increase the number of lead candidates, here we discuss a phylogeny-guided approach for the rational selection of venomous taxa, using tarantulas (family Theraphosidae) as a case study. We found that previous biodiscovery programs have prioritized the three subfamilies Ornithoctoninae, Selenocosmiinae, and Theraphosinae, which provide almost all of the toxin sequences currently available in public databases. The remaining subfamilies are poorly represented, if at all. These overlooked subfamilies include several that form entire clades of the theraphosid life tree, such as the subfamilies Eumenophorinae, Harpactirinae, and Stromatopelminae, indicating that biodiversity space has not been covered effectively for venom biodiscovery in Theraphosidae. Focusing on these underrepresented taxa will increase the likelihood that promising candidates with novel structures and mechanisms of action can be identified in future bioprospecting programs.

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Kumar V, Tyagi K, Chakraborty R, et al. The Complete Mitochondrial Genome of endemic giant tarantula, Lyrognathus crotalus (Araneae: Theraphosidae) and comparative analysis. Sci Rep. 2020;10(1):74. Published 2020 Jan 9. doi:10.1038/s41598-019-57065-8
The complete mitochondrial genome of Lyrognathus crotalus is sequenced, annotated and compared with other spider mitogenomes. It is 13,865 bp long and featured by 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (rRNAs), 13 protein-coding genes (PCGs), and a control region (CR). Most of the PCGs used ATN start codon except cox3, and nad4 with TTG. Comparative studies indicated the use of TTG, TTA, TTT, GTG, CTG, CTA as start codons by few PCGs. Most of the tRNAs were truncated and do not fold into the typical cloverleaf structure. Further, the motif (CATATA) was detected in CR of nine species including L. crotalus. The gene arrangement of L. crotalus compared with ancestral arthropod showed the transposition of five tRNAs and one tandem duplication random loss (TDRL) event. Five plesiomophic gene blocks (A-E) were identified, of which, four (A, B, D, E) retained in all taxa except family Salticidae. However, block C was retained in Mygalomorphae and two families of Araneomorphae (Hypochilidae and Pholcidae). Out of 146 derived gene boundaries in all taxa, 15 synapomorphic gene boundaries were identified. TreeREx analysis also revealed the transposition of trnI, which makes three derived boundaries and congruent with the result of the gene boundary mapping. Maximum likelihood and Bayesian inference showed similar topologies and congruent with morphology, and previously reported multi-gene phylogeny. However, the Gene-Order based phylogeny showed sister relationship of L. crotalus with two Araneomorphae family members (Hypochilidae and Pholcidae) and other Mygalomorphae species.

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Estrada-Gomez S, Cardoso FC, Vargas-Muñoz LJ, et al. Venomic, Transcriptomic, and Bioactivity Analyses of Pamphobeteus verdolaga Venom Reveal Complex Disulfide-Rich Peptides That Modulate Calcium Channels. Toxins (Basel). 2019;11(9):496. Published 2019 Aug 27. doi:10.3390/toxins11090496
Pamphobeteus verdolaga is a recently described Theraphosidae spider from the Andean region of Colombia. Previous reports partially characterized its venom profile. In this study, we conducted a detailed analysis that includes reversed-phase high-performance liquid chromatography (rp-HPLC), calcium influx assays, tandem mass spectrometry analysis (tMS/MS), and venom-gland transcriptome. rp-HPLC fractions of P. verdolaga venom showed activity on CaV2.2, CaV3.2, and NaV1.7 ion channels. Active fractions contained several peptides with molecular masses ranging from 3399.4 to 3839.6 Da. The tMS/MS analysis of active fraction displaying the strongest activity to inhibit calcium channels showed sequence fragments similar to one of the translated transcripts detected in the venom-gland transcriptome. The putative peptide of this translated transcript corresponded to a toxin, here named ω-theraphositoxin-Pv3a, a potential ion channel modulator toxin that is, in addition, very similar to other theraphositoxins affecting calcium channels (i.e., ω-theraphotoxin-Asp1a). Additionally, using this holistic approach, we found that P. verdolaga venom is an important source of disulfide-rich proteins expressing at least eight superfamilies.


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