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1.
Naturwissenschaften ; 108(6): 60, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34748107

RESUMO

Entanglements are common in both natural and artificial systems and can result in both beneficial and harmful effects. Most spider webs are static structures held under constant tension and do not tangle. However, many spiders actively load tension into their webs by coiling silk threads that are released to "fire" webs at prey. Here we test whether or not tangling occurs during the rapid release of webs built by the triangle spider Hyptiotes cavatus. We use high-speed videography to examine the release of the spider's web, looking for signs of tangling both visually on the videos and on acceleration graphs. The spider tenses the web by pulling on a silken anchor line using a leg-over-leg movement, deforming the silk into permanent coils and storing excess slack in a loose bundle between the spider's legs. This 1-3cm long bundle of coils straightens during the web's release in as few as 4ms. Though the messy silk coils are pressed closely together, the web's release is never impeded by catastrophic tangling. This lack of serious tangling is perhaps due to the permanent coils preventing random movement of the silk. The coils also compact the loose silk, preventing interference with the spider's movement. The ability to coil its anchor line allows H. cavatus to permanently restructure its silk, facilitating its active web-hunting behavior. Our findings broaden our knowledge of silk manipulation by spiders and may give insights into creating tangle-free systems through structural changes.


Assuntos
Seda , Aranhas , Animais , Comportamento Predatório
2.
Rev Med Chil ; 149(5): 682-688, 2021 May.
Artigo em Espanhol | MEDLINE | ID: mdl-34751320

RESUMO

BACKGROUND: Loxoscelism is an important public health problem in Chile and South America, due to the higher rate of cutaneous-visceral involvement. The diagnosis of loxoscelism is mostly clinical without established diagnostic criteria. There is little evidence to support any treatment used in this condition. AIM: To characterize the clinical features and epidemiology of loxoscelism among patients consulting at the Emergency and Dermatology Services of a clinical hospital between 2013 and 2017. MATERIAL AND METHODS: Review of medical records of patients registered in the electronic clinical record system with a confirmed diagnosis of loxoscelism. Epidemiological, clinical, laboratory tests and treatment variables were analyzed. RESULTS: We reviewed data from 200 patients. Ninety-four percent presented cutaneous loxoscelism and 5.5% cutaneous-visceral loxoscelism. Systemic symptoms were present in 73% of patients with cutaneous-visceral loxoscelism. Patients who developed systemic symptoms had an 18 times higher risk of developing cutaneous-visceral loxoscelism. Laboratory abnormalities were more common in patients with cutaneous-visceral loxoscelism. Not all patients with hematuria had cutaneous-visceral loxoscelism. Most patients required analgesia. Anti-loxosceles serum was not used in any patient. CONCLUSIONS: Many questions remain to be answered regarding the diagnosis and treatment of the disease. Studies are required to validate diagnostic criteria for loxoscelism, predictors for visceral involvement and response to treatment.


Assuntos
Picaduras de Aranhas , Venenos de Aranha , Aranhas , Animais , Chile/epidemiologia , Humanos , Dor , Picaduras de Aranhas/diagnóstico , Picaduras de Aranhas/epidemiologia , Picaduras de Aranhas/terapia
3.
Braz J Biol ; 84: e252088, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34755814

RESUMO

Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Assuntos
Acacia , Insetos , Aranhas , Animais , Biomarcadores Ambientais , Recuperação e Remediação Ambiental
4.
Zootaxa ; 5061(3): 559-572, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34810608

RESUMO

A new sun-spider species of the ibirapemussu species-group of the genus Gaucha is described based on males and a female collected in Southeastern Brazil. The newly described species can be readily distinguished from its congeners by the reduction of the cheliceral fixed finger, distal tooth (FD), closely positioned and smaller than the medial tooth (FM); the presence of cheliceral fixed finger profondal subproximal (PFSP) and retrofondal submedial (RFSM) teeth; and by the cheliceral movable finger, medial tooth (MM) well developed, larger than submedial tooth (MSM) and smaller than proximal tooth (MP). This is the thirteenth described species in the genus Gaucha, all known from South America.


Assuntos
Aracnídeos , Aranhas , Animais , Brasil , Feminino , Masculino
5.
Zootaxa ; 5020(3): 457-488, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34810991

RESUMO

The cribellate, Asian endemic, spider genus, Taira is further studied, and six new species are recognized and described from China and Eastern Malaysia (Borneo): Taira borneoensis sp. nov. (♀), Taira gyaisiensis sp. nov. (♀), Taira nyagqukaensis sp. nov. (♀), Taira wanzhouensis sp. nov. (♂♀), Taira xuanenensis sp. nov. (♂) and Taira yangi sp. nov. (♂♀). Males of Taira latilabiata Zhang, Zhu Song, 2008 and Taira obtusa Zhang, Zhu Song, 2008 are also described for the first time. Drawings of the copulatory organs of the six new species, and comparative photos of the habitus and copulatory organs of all described species are provided, except for the male palp of the type species, T. flavidorsalis (Yaginuma, 1964). New records of known species and distribution maps are presented.


Assuntos
Filogenia , Aranhas , Animais , Feminino , Masculino , Aranhas/classificação
6.
Zootaxa ; 5032(4): 533-548, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34811111

RESUMO

Seven new species of Otacilia Thorell, 1897 from China are described and illustrated, all from both sexes: O. ensifera sp. nov. and O. arcuata sp. nov. from Hunan Province; O. spiralis sp. nov. from Hunan Province and Chongqing City; O. lubrica sp. nov. and O. wuli sp. nov. from Chongqing City; O. dentigera sp. nov. from Sichuan Province; and O. shanxi sp. nov. from Shanxi Province. Based on Jin et al. (2016), the seven new species described here belong to two species groups: O. ensifera sp. nov., O. shanxi sp. nov., O. spiralis sp. nov. and O. lubrica sp. nov. belong to the armatissima-group, while O. wuli sp. nov., O. dentigera sp. nov. and O. arcuata sp. nov. belong to the longituba-group.


Assuntos
Aranhas , Distribuição Animal , Animais , China , Feminino , Masculino
7.
Zootaxa ; 5057(3): 115-128, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34811201

RESUMO

Three new species of zodariid spiders are described from Turkey: Zodarion ozkutuki spec. nov., Zodarion turkesi spec. nov. and Zodarion yagmuri spec. nov. New photographs of genitalia are provided for Zodarion van Bosmans 2009.


Assuntos
Aranhas , Distribuição Animal , Animais , Genitália , Turquia
8.
Zootaxa ; 5057(2): 241-259, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34811211

RESUMO

Gypogyna Simon, 1900 is revised. Three species are recognized and diagnosed. The type species, Gypogyna forceps Simon, 1900, is redescribed and recorded from several localities in South America. Gypogyna amazonica Ruiz sp. nov. is described based on a male from Manaus, Brazil. Gypogyna mexicana Ruiz Bustamante sp. nov. is described based on specimens of both sexes from the state of Jalisco, Mexico. In addition, some comments on cheliceral dentiton and genital morphology are discussed.


Assuntos
Aranhas , Distribuição Animal , Animais , Feminino , Masculino , Tamanho do Órgão
9.
Zootaxa ; 5057(1): 127-139, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34811218

RESUMO

A new genus and species of the tropiduchid planthopper of the tribe Tropiduchini is described as Bitara augusta gen. et sp. nov. from Madang Province, Papua New Guinea. It is the 18th species of Tropiduchini and the 9th genus known east of the Wallace line. It is another taxon with characteristic asymmetric genitalia within this tribe.


Assuntos
Hemípteros , Rubiaceae , Aranhas , Animais
10.
Zootaxa ; 5004(4): 564-576, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34811288

RESUMO

Three species of the genus Miagrammopes O. Pickard-Cambridge, 1870 are described from China, including two new species, M. rutundus Liang Xu, n. sp. from Guangxi Zhuang Autonomous Region and M. auriculatus Cai Xu, n. sp. from Tibet Autonomous Region, and one known species, M. bifurcatus Dong, Yan, Zhu Song, 2004. The female of M. bifurcatus is described for the first time. Both detailed illustration and a distribution map of the three species are provided.


Assuntos
Aranhas , Distribuição Animal , Animais , China , Feminino
11.
Zootaxa ; 5004(2): 201-250, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34811308

RESUMO

The genus Tupirinna Bonaldo, 2000 is revised, including 20 species. New records of T. rosae Bonaldo, 2000 from Par, Brazil are given. Tupirinna albofasciata (Mello-Leito, 1943) is redescribed based on the female lectotype, here designated. The following 17 new species are described, diagnosed, and illustrated: T. platnicki sp. nov. (♂ and ♀ from Par, Brazil); T. zebra sp. nov. (♂ and ♀ from Amazonas and Mato Grosso, Brazil); T. caraca sp. nov. (♂ and ♀ from south and southeast Brazil); T. urucu sp. nov. (♂ from Amazonas, Brazil); T. coari sp. nov. (♂ and ♀ from Amazonas, Brazil); T. lata sp. nov. (♂ and ♀ from the states of Bahia, Espirto Santo, Minas Gerais, So Paulo and Santa Catarina, Brazil); T. regiae sp. nov. (♂ and ♀ from Amazonas and Par, Brazil); T. mutum sp. nov. (♂ and ♀ from Par and Mato Grosso, Brazil); T. cruzes sp. nov. (♂ and ♀ from Rio de Janeiro, So Paulo and Santa Catarina, Brazil); T. palmares sp. nov. (♂ and ♀ from northeast Brazil); T. una sp. nov. (♂ and ♀ from Bahia, Brazil); T. gigantea sp. nov. (♂ and ♀ from Vaups, Colmbia and Peru); T. oba sp. nov. (♀ from Bahia, Brazil); T. goeldi sp. nov. (♀ from Par, Brazil); T. ibiapaba sp. nov. (♂ and ♀ from Cear, Brazil); T. luctuosa sp. nov. (♀ from Minas Gerais, Brazil) and T. araguaia sp. nov. (♂ and ♀ from Par, Brazil). Additionally, two species groups are delimited based on genitalic morphology. Distribution maps and an identification key to the males and females of all known species of Tupirinna are also provided.


Assuntos
Aranhas , Distribuição Animal , Animais , Brasil , Feminino , Genitália , Masculino
13.
Zootaxa ; 5020(1): 1-30, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34810422

RESUMO

Five new species of mimetid spiders from China are described: Mimetus subulatus n. sp., M. clavatus n. sp., M. dentatus n. sp., M. niveosignatus n. sp. and M. uncatus n. sp. The phylogenetic placement of these new species is inferred based on a cladistic analysis of an expanded version of the morphological dataset of Benavides and Hormiga (2020). The new species form a clade that can be distinguished from other Mimetus species by the presence of a subtegular apophysis between paracymbium and subtegulum, pilose cuticular projections on the membranous part of the conductor in the male palp and by a bicameral structure of the spermathecae in females. The new species are part of a clade that includes Mimetus syllepsicus Hentz, 1832, the type species of the genus. The genus Mimetus as currently circumscribed is not monophyletic, as the clade that includes all the Mimetus species also includes the genera Australomimetus Heimer, 1986 and Anansi Benavides and Hormiga, 2017, corroborating the results of Benavides and Hormiga (2020).


Assuntos
Aranhas , Distribuição Animal , Animais , China , Feminino , Masculino , Filogenia , Aranhas/genética
14.
Zootaxa ; 5016(4): 523-542, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34810432

RESUMO

Species of the genus Ectatosticta Simon, 1892 are studied from China, including seven known species E. bajie Lin Li, 2021 from Sichuan Prov., E. davidi (Simon, 1889) from Shaanxi, E. deltshevi Platnick Jger, 2009 from Qinghai, E. rulai Lin Li, 2021 from Sichuan, E. wukong Lin Li, 2020 from Sichuan, E. xuanzang Lin Li, 2020 from Tibet, E. yukuni Lin Li, 2021 from Shaanxi, and four new species: E. nyingchiensis sp. nov. from Tibet, E. pingwuensis sp. nov. from Sichuan, E. shennongjiaensis sp. nov. from Hubei and E. songpanensis sp. nov. from Sichuan. We provide detailed descriptions, including DNA barcode information, and images of all the species.


Assuntos
Aranhas , Animais , China , DNA , Aranhas/genética
15.
Zootaxa ; 5016(3): 333-364, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34810444

RESUMO

Originally described from Greenland, Juxtacribrilina annulata (Fabricius, 1780) (previously known as Cribrilina annulata) has long been regarded as having a circumpolar, Arctic-boreal distribution. The genus Juxtacribrilina Yang, Seo, Min, Grischenko Gordon, 2018 accommodated J. annulata and three related North Pacific species formerly in Cribrilina Gray, 1848 that lack avicularia, have a reduced (hood-like, cap-like, or vestigial) ooecium closely associated with modified latero-oral spines to form an ooecial complex, and produce frontally or marginally positioned dwarf ovicellate zooids. While the recently described NW Pacific species J. mutabilis and J. flavomaris, which have a vestigial ooecium like a short, flattened spine, clearly differ from J. annulata, the differences between J. annulata and other Pacific populations remained unclear. Here we provide descriptions for five species from the North Pacific region. We identified a specimen from the Sea of Okhotsk as J. annulata. Among the other four species, J. ezoensis n. sp. has a trans-Pacific distribution (abundant at Akkeshi, Hokkaido, Japan; also detected in the Commander Islands and at Ketchikan, Southeast Alaska); J. pushkini n. sp. was found only at Ketchikan; J. dobrovolskii n. sp. was found only at Shikotan Island in the Lesser Kuril Chain; and J. tumida n. sp. was found only at Kodiak, Gulf of Alaska. These four species all differ from J. annulata in having one or two frontal pore chambers on the proximal gymnocyst of most zooids; in budding frontal dwarf ovicellate zooids from these chambers rather than from basal pore chambers; in producing dwarf zooids more abundantly; and in having ooecia that are somewhat to markedly more reduced (cap-like rather than hood-like) and more closely integrated with the modified latero-oral spines. Furthermore, in the Pacific species, the ooecium in basal zooids arises from the roof of the distal pore chamber of the maternal zooid; ovicellate zooids can thus also bud a distal autozooid and are often arranged in columnar series with other zooids. In J. annulata, the hood-like kenozooidal ooecium budded from the maternal zooid replaces the distal autozooid, and ovicellate zooids are thus usually not embedded in a columnar series.


Assuntos
Briozoários , Aranhas , Animais
16.
Zootaxa ; 4999(1): 77-86, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34810502

RESUMO

The castianeirine spider genus Myrmecotypus O. Pickard-Cambridge, 1894 is reported from Paraguay for the first time, with the description of a new species, Myrmecotypus mboitui sp. nov. (♂♀) from the eembuc Wetlands Complex of south-western Paraguay. The species belongs to a small group of Myrmecotypus with elongated and constricted abdomens. Illustrations of the diagnostic characters of the new species are provided. An updated key to the species of Myrmecotypus is presented.


Assuntos
Aranhas , Animais , Paraguai
17.
Zootaxa ; 5006(1): 208-212, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34810574

RESUMO

An illustrated description of Raveniola mikhailovi sp. n. from Chatkal Mt. Ridge is provided. The new taxon resembles R. virgata (Simon, 1891); it differs from the latter species in having a somewhat more compact eye group, combined with a narrower tegulum and a relatively longer embolus, and with noticeably longer inner stalks of the spermathecae.


Assuntos
Aranhas , Distribuição Animal , Animais
18.
Zootaxa ; 5006(1): 195-207, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34810575

RESUMO

The monotypic genus Bucliona Benoit, 1977 (type Clubiona dubia O. Pickard-Cambridge, 1870 from Saint Helena Island), previously considered a junior synonym of Clubiona Latreille, 1804, is resurrected. Three species are assigned to the genus Bucliona: B. dubia comb. reval., B. kirilli sp. n. (♂, Kenya), and B. jucunda (Karsch, 1879) comb. n., ex Clubiona (♂♀, Far East Asia).


Assuntos
Aranhas , Animais , Quênia
19.
Zootaxa ; 5006(1): 110-120, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34810581

RESUMO

A new speciesChinattus mikhailovi sp. nov. (♂♀, from Pakistan, Peshawar)is diagnosed, described and illustrated. New records of Chinattus validus (Xie, Peng et Kim, 1993) from Nepal, India (Himachal Pradesh) and Vietnam, and C. chichila Logunov, 2003 from Nepal are presented. The collecting localities of all three species are mapped. A brief discussion of the state of knowledge of the genus Chinattus Logunov, 1999 is provided as well.


Assuntos
Aracnídeos , Aranhas , Animais , Índia , Nepal , Paquistão
20.
Zootaxa ; 5006(1): 73-89, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34810586

RESUMO

A new species, Dysdera mikhailovi sp. nov. (♀), is described from Tajikistan (nr. Dushanbe). A poorly known species Dysdera subcylindrica Charitonov, 1956 from Central Asia is redescribed based on newly collected material. Dysdera dushengi Lin, Chang et Li, 2020, known from western Xinjiang (China) is reported from Kazakhstan for the first time. (Re)descriptions, figures, diagnoses and distribution maps of all the studied species are provided.


Assuntos
Aranhas , Animais
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