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1.
Zootaxa ; 3795: 441-8, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24870488

RESUMO

Miroculis stenopterus, sp. nov., is described based on material from State of Pernambuco, Northeastern Brazil. The imago of the new species can be distinguished, among other characteristics, by an uncommon forewing shape, long and narrow, similar to species of genus Microphlebia. The tentatively associated nymph can be distinguished from other species of the genus mainly by the abdominal color pattern and the ratio of labial palp segment 2 to segment 1 (1.01-1.04 x).


Assuntos
Biodiversidade , Insetos/anatomia & histologia , Animais , Brasil , Masculino , Ninfa/anatomia & histologia
2.
Phys Rev E ; 109(4-1): 044313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38755908

RESUMO

We present a multiscale stochastic analysis of foreign exchange rates using the H-theory formalism, which provides a hierarchical intermittency model for the information cascade in the currency market. We examine the distributions of returns and volatilities for the three most traded currency pairs: euro-U.S. dollar, U.S. dollar-Japanese yen, and British pound-U.S. dollar. We find that these markets have a hierarchy of timescales, with larger markets exhibiting more hierarchy levels. We provide a theoretical framework for understanding why the number of levels in the information cascade increases with market size, in analogy with similar behavior for the energy cascade in turbulence as a function of Reynolds number. We briefly argue that using turbulence-like models for financial markets can also provide valuable insights for developing efficient algorithmic trading strategies.

3.
Zootaxa ; 3709: 230-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26240907

RESUMO

Four new species of the mayfly genus Thraulodes Ulmer are described based on imagos from Northeastern and Southern Brazil: Thraulodes luizgonzagai sp. nov., Thraulodes sternimaculatus sp. nov., Thraulodes alapictus sp. nov., and Thraulodes pinhoi sp. nov. The new species can be easily differentiated by the abdominal color pattern and genitalia morphology. The first key to adults from Brazil is provided.


Assuntos
Ephemeroptera/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ephemeroptera/anatomia & histologia , Ephemeroptera/crescimento & desenvolvimento , Feminino , Masculino , Tamanho do Órgão
4.
Zootaxa ; 3700: 583-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26106745

RESUMO

The Hydroptilidae constitute the most diverse and widespread family of Trichoptera in the world. About 90 species of microcaddisflies have been recorded from Brazil, but the northeastern region is one of the least-sampled. In this work we describe a new species of Metrichia from Pernambuco State. Furthermore, we present the first records of Flintiella andreae Angrisano 1995 and Oxyethira bettyae Thomson & Holzenthal 2012 from Brazil, and four other new records from the northeastern region.


Assuntos
Distribuição Animal/fisiologia , Insetos/anatomia & histologia , Insetos/classificação , Animais , Brasil , Especificidade da Espécie
5.
Zootaxa ; 5230(1): 27-47, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37044859

RESUMO

The genus Miroculis Edmunds, 1963 (Ephemeroptera: Leptophlebiidae) is endemic to South American with 27 described species. In Brazil, 21 of these are known to occur. The present paper describes three new species of Miroculis Edmunds, 1963. Miroculis (Miroculis) botafora sp. nov. is described based on a male imago collected in a transition area between the Cerrado and Caatinga biomes in Piauí State, Brazil. Two species are described based on nymphs and adults: Miroculis (Miroculis) azevedoi sp. nov. and Miroculis (Miroculis) quilombola sp. nov.; both were collected in a Cerrado region of Maranhão State, Brazil. Additionally, new distribution records of Miroculis (Miroculis) fittkaui Savage & Peters, 1983 are provided.


Assuntos
Ephemeroptera , Masculino , Animais , Brasil , Ninfa , Ecossistema
6.
Zootaxa ; 5339(3): 237-255, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38221055

RESUMO

Caenidae is a globally widespread family, inhabiting a variety of aquatic habitats. In South America, only 35 species are recognized, maybe as a consequence of the few studies until the first decade of the 21st century. Despite recent advances, large portions of Brazil, such as Rondnia State, are still characterized by Linnean and Wallacean shortfalls. Rondnia is an area predicted to have high mayfly richness, but with no record of Caenidae. From this perspective, the objective of this study is to provide the first access to primary biodiversity data of Caenidae (Ephemeroptera) from Rondnia. As result, we report five species (Brasilocaenis elidioi, Brasilocaenis irmleri, Caenis chamie, Caenis fittkaui, Latineosus sigillatus) and describe a new species based on all life stages (Caenis urupa sp. nov.).


Assuntos
Ephemeroptera , Animais , Brasil , Insetos , Ecossistema , Biodiversidade
7.
Zootaxa ; 5133(1): 110-122, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-36101109

RESUMO

New distributional records for four species and the description of a new species of Caenis Stephens from Parnaba River Basin, in a semiarid region of the state of Piau, Northeastern Brazil are given. Characters and illustrations to distinguish Caenis marataoan sp. nov. from all other species in Caenis are provided. The new species can be distinguished by the following combination of characters: 1) body length of male 1.52.0 mm, female 2.52.8 mm; 2) base of antennal flagellum not dilated; 3) forceps apically rounded, covered with trichomes and with 23 minute spines at apex; 4) styliger plate short with posterior margin convex; 5) penis fused and not laterally projected; 6) eggs oval-shaped; micropyle linear with narrow and long micropylar canal, preceded by an oval sperm guide.


Assuntos
Ephemeroptera , Animais , Brasil , Feminino , Masculino , Pênis , Sêmen
8.
Zootaxa ; 5100(1): 73-88, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35391088

RESUMO

Hagenulopsis diptera Ulmer, type species of the genus Hagenulopsis, was originally described based on imagos from Santa Catarina State, Southern Brazil. Misconceptions of H. diptera circumscription led to erroneous attribution of material from Minas Gerais and Esprito Santo, Southeastern Brazil, to H. diptera. Despite the increase in the number of species attributed to Hagenulopsis, little attention has been given to the type species. After comparative examination of photographs of the holotype and fresh material of H. diptera from Southeastern Brazil, we conclude that many specimens previously assigned to H. diptera represent a new species. Thus, we redescribe H. diptera and describe a new species Hagenulopsis perere sp. nov. based on eggs, nymphs and imagos. Diagnostic features of Hagenulopsis perere sp. nov. include cross veins between C and RP1 strongly clouded with brown and outer surface of mid femur with a brown spot at midlength. Finally, comments and new records are presented for Hagenulopsis minuta Spieth.


Assuntos
Ephemeroptera , Animais , Brasil , Ninfa
9.
Zootaxa ; 5027(1): 136-144, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34811240

RESUMO

Brasilocaenis atawallpa was recently described based on male imago from Colombian Amazon. The original description does not contain a designation of type specimens or locality, and it just states that the type series was studied in order to perform the cladistic analysis. In this context, we herein designate the lectotype and paralectotypes of B. atawallpa and describe its nymphal stage. The nymphs were associated to B. atawallpa by the male genitalia extracted from mature nymphs. The nymphal stage of B. atawallpa can be differentiated from others known nymphs of the genus by absence of pointed microspines on opercular gill, fore coxa without projection, middle coxa with well-developed and semicircular projection, hind coxa with finger-like projection, fore and middle tarsal claws without denticles and hind margin of the ninth sternite almost straight.


Assuntos
Bivalves , Ephemeroptera , Holometábolos , Animais , Brânquias , Masculino , Ninfa
10.
Zootaxa ; 4861(3): zootaxa.4861.3.7, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33311217

RESUMO

The genus Traverella Edmunds, 1948 (Ephemeroptera: Leptophlebiidae) has 15 described species, three of them recorded from Brazil: Traverella bradleyi (Needham Murphy, 1924), T. insolita Nascimento Salles, 2013 and T. maranhensis Nascimento, Lima Azevedo, 2019. In the present work, we provide the description of a new species to the genus based on nymphs and male imagos and provide description of the nymphal stage of T. maranhensis, based on collections from Maranhão State. Additionally, an updated key of male imagos is provided.


Assuntos
Ephemeroptera , Animais , Brasil , Masculino , Ninfa
11.
Zootaxa ; 4768(4): zootaxa.4768.4.10, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33055643

RESUMO

Hermanellopsis Demoulin, 1955 is a genus of Leptophlebiidae known from adults of both sexes and is represented solely by two species, both from South America: Hermanellopsis arsia Savage Peters, 1983, described only from male subimago; and H. incertans (Spieth, 1943) described from male imago and female subimago. Edmunds et al. (1976) provided the generic description for the supposed nymph of Hermanellopsis. However, Savage Peters (1983) revised the genus, and study of related genera raised doubt about the identity of the proposed nymph. Thus, the nymph of Hermanellopsis has remained unknown until now.


Assuntos
Ephemeroptera , Animais , Brasil , Feminino , Masculino , Ninfa
12.
Zootaxa ; 4838(2): zootaxa.4838.2.6, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-33056825

RESUMO

Some regions, such as the Northeast Region of Brazil, are still severely understudied and the trichopteran fauna of this region is not entirely known, mainly in areas from Cerrado and Caatinga biomes. Currently, 25 species have been reported from Piauí State, but most of these records are concentrated from one locality. This study aimed to update the knowledge of Trichoptera diversity in this state, including the description of a new species and new geographic records for the Northeast region and Brazil. The samples were collected in seven municipalities, using various traps. Specimens were also received from the municipality of Bom Jesus. Thirty-two species were added for Trichoptera fauna of Piauí, 14 of these represent new records for Northeast Brazil; furthermore, Neotrichia palma Flint 1982 is a new record for Brazil. Additionally, a new species, Cernotina longa sp. nov., is describe and illustrate, being the third nominal record of the genus for the Caatinga biome. Thus, with the contribution of this study, 57 species, 20 genera and seven families of caddisflies are known for Piauí State.


Assuntos
Holometábolos , Insetos , Animais , Brasil , Geografia
13.
J Cell Biol ; 91(1): 201-11, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7197680

RESUMO

Human blood platelets, which are highly motile cells essential for the maintenance of hemostasis, contain large quantities of actin and other contractile proteins. We have previously introduced a method (Lucas, R. C., T. C. Detwiler, and A. Stracher, J. Cell Biol., 1976, 70(2, Pt. 2):259 a) for the quantitative recovery of the platelets' cytoskeleton using a solution containing 1% Triton X-100 and 10 mM EGTA. This cytoskeleton contains most of the platelets' actin, actin-binding protein (ABP, subunit molecular weight = 260,000), and a 105,000-dalton protein. Negative staining of this Triton-insoluble residue on an EM grid shows it to consist of branched cables of actin filaments aligned in parallel. When this cytoskeletal structure is dissolved in high-salt solutions, the actin and ABP dissociate and can subsequently be separated. Here we will present simple and rapid methods for the individual purifications of platelet actin and platelet ABP. When purified actin and ABP are recombined in vitro, they are shown to be both necessary and sufficient for the reformation of the cytoskeletal complex. The reformed structure is visualized as a complex array of fibers, which at the EM level are seen to be bundles of actin filaments. The reformation of the cytoskeleton requires only that the actin be in the filamentous form--no accessory proteins, chelating agents, divalent cations, or energy sources are necessary. In vivo, however, the state of assembly of the platelets' cytoskeleton appears to be under the control of the intracellular concentration of free calcium. Under conditions where proteolysis is inhibited and EGTA is omitted from the Triton-solubilization step, no cytoskeleton can be isolated. The ability of Ca+2 to control the assembly and disassembly of the platelets' cytoskeleton provides a mechanism for cytoskeletal involvement in shape change and pseudopod formation during platelet activation.


Assuntos
Actinas/isolamento & purificação , Plaquetas/análise , Proteínas de Transporte/isolamento & purificação , Proteínas Contráteis/isolamento & purificação , Cálcio/farmacologia , Citoesqueleto/ultraestrutura , Eletroforese em Gel de Poliacrilamida , Géis , Humanos , Peso Molecular , Ligação Proteica/efeitos dos fármacos
14.
Zootaxa ; 4683(2): zootaxa.4683.2.7, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31715930

RESUMO

Thraulodes Ulmer, 1920 is one of the most abundant and widespread genera of Leptophlebiidae represented by 66 species (Barber-James et al. 2013; Gonçalves et al. 2013; Lima et al. 2013; Souto et al. 2014; Zúñiga et al. 2015; Boldrini et al. 2018; Campos Mariano 2019). Its distribution extends from Central Argentina in the Neotropics to the Neartic Region. For Brazil, 23 species are known (Salles Boldrini 2019), but only seven species are known from both adult and nymphal stages: T. bonito Gonçalves, Da-Silva Nessimian; T. cochunaensis Domínguez; T. daidaleus Traver Edmunds; T. jones Gonçalves, Da-Silva Nessimian; T. itatiajanus Traver Edmunds; T. schlingeri Traver Edmunds and T. traverae Thew (Thew 1960; Traver Edmunds 1967; Domínguez 1987; Lopes et al. 2003; Gonçalves et al. 2010; Gonçalves et al. 2013).


Assuntos
Bivalves , Ephemeroptera , Animais , Argentina , Brasil , Ninfa
15.
Zootaxa ; 4619(1): zootaxa.4619.1.12, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716324

RESUMO

A new species of Traverella Edmunds (Ephemeroptera: Leptophlebiidae) is described based on male imagoes from the state of Maranhão, northeastern Brazil. The main characteristics that distinguish the new species from the other species are: 1) subgenital plate forming two lateral, broad projections with two fine, long spines dorsally recurved; 2) penis lobe triangular and apically rounded, with a small ventral projection at apex and a ventral longspine slightly curved and directed to midline.


Assuntos
Ephemeroptera , Animais , Brasil , Masculino
17.
Zootaxa ; 4461(2): 253-260, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30314086

RESUMO

Simothraulopsis Demoulin, 1966 is a Neotropical genus of Leptophlebiidae with nine species known from South America. In the present paper, based on male imagos from the northeastern region of Brazil in the states of Alagoas and Piauí, two new species of the Simothraulopsis are described: Simothraulopsis sinuosus sp. nov. and Simothraulopsis gracilianus sp. nov.


Assuntos
Ephemeroptera , Animais , Brasil , Masculino
18.
Zootaxa ; 4459(2): 395-400, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30314117

RESUMO

A new species Coryphorus is presented,  based on recent collections from Northeastern Brazil and specimens deposited in the Museu Regional de Entomologia da Universidade Federal de Viçosa (UFVB) and Coleção Zoológica da Universidade Federal de Roraima (UFRR). Coryphorus molinerii sp. nov. is described based on male imagos and can be distinguished by the penis with rounded margins and forceps with segment II narrow and sharpening towards apex. Besides, C. aquilus Peters, (1981) is reported for Tocantins State for the first time.


Assuntos
Ephemeroptera , Animais , Brasil , Masculino , Pênis
19.
Zootaxa ; 4276(2): 285-292, 2017 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-28610212

RESUMO

The genus Caenis Stephens, 1835 is well represented in South America with 24 recorded species (14 in Brazil). Based on additional material from Brazil, we describe for the first time the nymphal and egg stages of C. reissi, and re-describe the eggs of C. cuniana. New distributional records for these species and Caenis elidioi are given, and C. teipunensis (previously described from Venezuela) is reported for the first time from Brazil.


Assuntos
Ephemeroptera , Estruturas Animais , Animais , Tamanho Corporal , Brasil , Tamanho do Órgão
20.
Zootaxa ; 4170(1): 114-124, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27701276

RESUMO

Caenis Stephens, 1835 is a relatively diverse South American genus of Caenidae (Ephemeroptera), with 22 recorded species, but much of its diversity remains poorly explored in this region. In the present study, two new species of Caenis with apically pointed forceps are described: Caenis amacayacu sp. nov., based on male adults from Colombia; and C. elidioi sp. nov, based on all life stages from several localities in Brazil.


Assuntos
Ephemeroptera/anatomia & histologia , Ephemeroptera/classificação , Animais , Brasil , Ephemeroptera/ultraestrutura , Feminino , Masculino , Microscopia Eletrônica de Varredura , Especificidade da Espécie
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