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1.
Zootaxa ; 4851(2): zootaxa.4851.2.11, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33056735

RESUMO

Xiphocentron is the most species-rich genus of the pantropical family Xiphocentronidae. Among its five subgenera, Antillotrichia is the most diverse and the only one to occur in South America and Antilles. In the present study, two new species of Xiphocentron (Antillotrichia) are described from southern Atlantic Forest, Brazil. Xiphocentron gwarakeraba sp. nov. is diagnosed by the very elongate inferior appendage not bearing spines and with a simple mesal sclerite; X. muelleri sp. nov. is diagnosed by the inferior appendage with its ventral margin produced posterad and distinctly truncate. New distributional records are provided for X. acqualume, X. jaguare, X. kamakan, and X. maracanan. Additional non-genital diagnostic characters are presented for X. jaguare, and intraspecific morphological variations of forewing fork II (R3 and R4) and male genitalia are described for X. maracanan.


Assuntos
Holometábolos , Insetos , Animais , Brasil , Florestas , Masculino , Registros
2.
Zootaxa ; 4819(1): zootaxa.4819.1.2, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055669

RESUMO

The genus Hexacylloepus extends from the Neotropical region to the southwestern United States of America. At present, 25 species are known from 20 countries, with no new species proposed since 1972. In this paper, we describe and illustrate 18 new species (H. barrae; H. calori; H. casariae; H. froehlichi; H. geiseri; H. grandis; H. iassu; H. keitai; H. maierae; H. manauara; H. metapa; H. phalluspilosus; H. shorti; H. taylorae; H. thoracica; H. tibialis; H. ubirajarai; H. zaninii), from eight countries and give the first records of the genus from Suriname and Guyana.


Assuntos
Besouros , Animais
3.
Arthropod Struct Dev ; 53: 100884, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31669831

RESUMO

Iridescence is an optical effect that produces angle dependent coloration in animals. Recently, studies have attempted to unveil structures behind such elaborated visual signals and associated behaviors in Odonata. Here, we studied males of the Amazonian damselfly Chalcopteryx scintillans, which have hindwings that exhibit pronounced iridescence. This optical feature is used by the damselflies for intra-specific communication during territorial fights and courtship. The main question we addressed was whether male wing structural coloration may predict the outcome of male-male contests. We also studied the wing ultrastructure, in order to reveal the mechanisms that are responsible for wing coloration. Using various microscopal and spectroscopal techniques, we demonstrate that hindwing coloration is derived from two main effects: (1) light interference in the cuticle multilayer and (2) a specific angle dependent light scattering and antireflective properties of the epicuticular wax coverage. The results of our field experiment show that wing pigmentation and the hue of the dorsal surface of the hindwings is correlated with the outcome of territorial contests. This is one of the first studies showing that structural coloration derived from multilayer interference may influence the outcome of intrasexual agonistic interactions. This indicates that multicomponent structural coloration in visually guided insects may be under selective forces of male-male competition for resources and females.


Assuntos
Cor , Iridescência , Odonatos/fisiologia , Pigmentos Biológicos/análise , Asas de Animais/fisiologia , Agressão , Animais , Sinais (Psicologia) , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Pigmentação , Asas de Animais/ultraestrutura
4.
Biol Lett ; 13(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28515332

RESUMO

Some consider that the first winged insects had living tissue inside the wing membrane, resembling larval gills or developing wing pads. However, throughout the developmental process of the wing membrane of modern insects, cells and tracheoles in the lumen between dorsal and ventral cuticle disappear and both cuticles become fused. This process results in the rather thin rigid stable structure of the membrane. The herewith described remarkable case of the dragonfly Zenithoptera lanei shows that in some highly specialized wings, the membrane can still be supplemented by tracheae. Such a characteristic of the wing membrane presumably represents a strong specialization for the synthesis of melanin-filled nanolayers of the cuticle, nanospheres inside the wing membrane and complex arrangement of wax crystals on the membrane surface, all responsible for unique structural coloration.


Assuntos
Odonatos , Animais , Asas de Animais
5.
Zootaxa ; 4158(2): 292-300, 2016 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-27615887

RESUMO

Erythrodiplax ana sp. nov. (male holotype, six male and three female paratypes), collected in Vereda wetlands (a unique Neotropical savanna environment) in Uberlândia (Minas Gerais) and Chapada dos Guimarães (Mato Grosso), Brazil, is described and illustrated. The new species fits in Borror's Basalis Group, and can be distinguished from other species by the combination of the following traits: blue pruinosity dorsally on thorax and third to eighth abdominal segments; sides of the thorax olive-green; face ivory or olive-green; wings hyaline with a small apical brown spot on all four wings, well defined in females; male genitalia with sclerotized erectile posterior lobe and inflatable sac-like median process. Last instar larvae were reared in the laboratory, resulting in the description of the larva. We also followed this population for 13 months and present resulting biological notes and comments on ontogenetic color change in males, as well as longevity.


Assuntos
Odonatos/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ecossistema , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Odonatos/anatomia & histologia , Odonatos/crescimento & desenvolvimento , Tamanho do Órgão , Áreas Alagadas
6.
J Insect Physiol ; 81: 129-36, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26188874

RESUMO

Zenithoptera dragonflies are known for their remarkable bluish colouration on their wings and unique male behaviour of folding and unfolding their wings while perching. However, nothing is known about the optical properties of such colouration and its structural and functional background. In this paper, we aimed to study the relationship between the wing membrane ultrastructure, surface microstructure and colour spectra of male wings in Zenithoptera lanei and test the hypothesis that colouration functions as a signal in territorial fights between males. The results show that the specific wing colouration derives from interference in alternating layers of melanized and unmelanized cuticle in the wing membrane, combined with diffuse scattering in two different layers of wax crystals on the dorsal wing surface, one lower layer of long filaments, and one upper layer of leaf-shaped crystals. The results also show that the thicker wax coverage of the dorsal surface of the wings results in increased brightness and reduced chroma. In the field experiments, we have demonstrated that there is a reduction of aggressive reactions of rivals towards individuals with experimentally reduced amount of blue wing colouration.


Assuntos
Cor , Odonatos/fisiologia , Odonatos/ultraestrutura , Asas de Animais/fisiologia , Agressão , Comunicação Animal , Animais , Masculino , Microscopia Eletrônica de Varredura , Pigmentação , Ceras , Asas de Animais/ultraestrutura
7.
Naturwissenschaften ; 102(3-4): 13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25776927

RESUMO

Wing pigmentation is a trait that predicts the outcome of male contests in some damselflies. Thus, it is reasonable to suppose that males would have the ability to assess wing pigmentation and adjust investment in a fight according to the costs that the rival may potentially impose. Males of the damselfly Mnesarete pudica exhibit red-coloured wings and complex courtship behaviour and engage in striking male-male fights. In this study, we investigated male assessment behaviour during aerial contests. Theory suggests that the relationship between male resource-holding potential (RHP) and contest duration describes the kind of assessment adopted by males: self-assessment, opponent-only assessment or mutual assessment. A recent theory also suggests that weak and strong males exhibit variations in the assessment strategies adopted. We estimated male RHP through male body size and wing colouration (i.e. pigmentation, wing reflectance spectra and transmission spectra) and studied the relationship between male RHP and contest duration from video-documented behavioural observations of naturally occurring individual contests in the field. The results showed that males with more opaque wings and larger red spots were more likely to win contests. The relationships between RHP and contest durations partly supported the self-assessment and the mutual assessment models. We then experimentally augmented the pigmented area of the wings, in order to evaluate whether strong and weak males assess rivals' RHP through wing pigmentation. Our experimental manipulation, however, clearly demonstrated that strong males assess rivals' wing pigmentation. We finally suggest that there is a variation in the assessment strategy adopted by males.


Assuntos
Odonatos/anatomia & histologia , Comportamento Sexual Animal/fisiologia , Animais , Comportamento Competitivo/fisiologia , Masculino , Modelos Biológicos , Pigmentação/fisiologia , Asas de Animais/anatomia & histologia
8.
Zootaxa ; 3835(1): 140-4, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-25081441

RESUMO

The gripopterygid genus Tupiperla comprises 18 species, 16 have been recorded from Brazil, including T. guariru n. sp., described here. The new species was collected from streams in the Serra da Jibóia region, Bahia State, Brazil using light traps. Additional material from Amargosa, Bahia State, Brazil was also studied.


Assuntos
Insetos/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Feminino , Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Masculino , Tamanho do Órgão
9.
Neotrop Entomol ; 37(2): 126-30, 2008.
Artigo em Português | MEDLINE | ID: mdl-18506289

RESUMO

This study aimed at evaluating the effect of collect time (day and night) on ant fauna attracted to baits in areas of Eucalyptus cloeziana (Myrtaceae) and cerrado. The ants were collected in Fazenda Boa Vista, Mannesmann Fi - El Florestal Ltda, Paineiras, Minas Gerais State. Eigthteen sample units were collected: 12 in E. cloezina and six in cerrado. Each sample unit consisted of three plots (25 x 35 m each). The plot consisted of 34 baits distributed in a grid pattern at 5 m intervals. The sampling was carried out in the diurnal and nocturnal period. The results obtained revealed that both type of vegetation (cerrado x Eucalyptus) and the collect time (day x night) had a significative influence on the epigaeic ant fauna. The ordination (DCA) indicated that collect time effect was more important to fauna structuration than the vegetation effect. Brachymyrmex sp.1, Brachymyrmex sp.2, Camponotus crassus Mayr, Camponotus rufipes (Fabricius), Cephalotes pusillus (Klug) and Ectatomma brunneum Smith were indicator species of nocturnal period, and Camponotus renggeri-Emery, Camponotus atriceps (Smith), Camponotus melanoticus Emery and Paratrechina sp.1 were indicators of nocturnal period.


Assuntos
Formigas , Animais , Formigas/classificação , Entomologia/métodos , Eucalyptus , Fatores de Tempo
10.
Neotrop. entomol ; 37(2): 126-130, Mar.-Apr. 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-483195

RESUMO

O presente estudo teve como objetivo avaliar o efeito do turno de coleta (dia e noite) na composição faunística de formigas epigéicas visitantes de iscas em áreas plantadas por Eucalyptus cloezina (Myrtaceae) e de vegetação nativa, cerrado. As coletas foram realizadas na Fazenda Boa Vista, Mannesmann Fi - El Florestal Ltda, localizada em Paineiras, MG. Foram coletadas 18 unidades amostrais: 12 em área com eucalipto e seis em área de cerrado. Cada unidade amostral foi composta de três parcelas (25 x 35 m cada), sendo que, em cada uma delas, foram distribuídas 34 iscas em grade, de 5 m em 5 m. Cada unidade amostral foi amostrada durante o dia e durante a noite. Os resultados revelaram que tanto o tipo de vegetação (cerrado e eucalipto), quanto o turno de coleta (dia e noite) influenciaram significativamente a fauna de formigas epigéicas. A ordenação (DCA) indica que o efeito dia e noite foi mais importante para a estruturação das diferentes comunidades do que o efeito da vegetação. Brachymyrmex sp.1, Brachymyrmex sp.2, Camponotus crassus-Mayr, Camponotus rufipes-(Fabricius), Cephalotes pusillus-(Klug) e Ectatomma brunneum Smith foram as espécies indicadoras do turno diurno, enquanto que Camponotus renggeri-Emery, Camponotus atriceps-(Smith), Camponotus melanoticus-Emery e Paratrechina sp. 1 foram indicadoras do turno noturno.


This study aimed at evaluating the effect of collect time (day and night) on ant fauna attracted to baits in areas of Eucalyptus cloeziana (Myrtaceae) and cerrado. The ants were collected in Fazenda Boa Vista, Mannesmann Fi - El Florestal Ltda, Paineiras, Minas Gerais State. Eigthteen sample units were collected: 12 in E. cloezina and six in cerrado. Each sample unit consisted of three plots (25 x 35 m each). The plot consisted of 34 baits distributed in a grid pattern at 5 m intervals. The sampling was carried out in the diurnal and nocturnal period. The results obtained revealed that both type of vegetation (cerrado x Eucalyptus) and the collect time (day x night) had a significative influence on the epigaeic ant fauna. The ordination (DCA) indicated that collect time effect was more important to fauna structuration than the vegetation effect. Brachymyrmex sp.1, Brachymyrmex sp.2, Camponotus crassus Mayr, Camponotus rufipes (Fabricius), Cephalotes pusillus (Klug) and Ectatomma brunneum Smith were indicator species of nocturnal period, and Camponotus renggeri-Emery, Camponotus atriceps (Smith), Camponotus melanoticus Emery and Paratrechina sp.1 were indicators of nocturnal period.


Assuntos
Animais , Formigas , Formigas/classificação , Eucalyptus , Entomologia/métodos , Fatores de Tempo
11.
Rev. bras. entomol ; 48(1): 133-134, mar. 2004.
Artigo em Inglês | LILACS | ID: lil-389166

RESUMO

The frequent occurrence of Triplectides sp. larvae in cases of Nectopsyche Müller in Ribeirão Bocaina, Parque Estadual Intervales, São Paulo, Brazil is recorded. Leaf packs were collected from November 1999 to June 2000 in riffles and pools. Triplectides sp. larvae in cases of Nectopsyche were found mostly in pools.


Assuntos
Comunicação , Insetos , Larva
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