60 resultados para Genitalia


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The aim of this work was to describe a new cricket species from the Iguacu National Park, Southeastern Brazil. We characterize the genitalia and external morphology of Tafalisca paranaensis n. sp. and the genitalia of Tafalisca paulista Rehn, 1918 providing a comparison between these species.

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Pseudacteon wasmanni is a South American decapitating fly that parasitizes workers of Solenopsis fire ants. We used light microscopy (historesin serial-sectioning stained with Haematoxylin/Eosin) and scanning electron microscopy to show and analyze internal and whole external views of the female reproductive system. All specimens analyzed (n = 9) by light microscopy showed post-vitellogenic oocytes inside the ovaries. The lack of typical follicles (oocyte-nurse cell complexes) in all specimens suggests that oogenesis occurs during the pupal stage. The total number of eggs found ranged from 31 to 280 (X = 142 +/- 73, SD). The egg has a slugform or torpedo shape (about 130 by 20 mum) with a pointed apex at the posterior pole as defined by the fly; the micropyle appears to be in a depression or invagination at the anterior pole. An acute hypodermic-like ovipositor is evaginated from the hard sclerotized external genitalia during egg laying. The existence of a muscular bulb associated with the end of the common oviduct suggests that the egg is injected into the ant's body by a strong contraction of the bulb which probably is stimulated by bending of several ventral sensilla. During contraction, the abdomen extends out along a large fold between the sixth and seventh tergites in such a way that the sclerotized genitalia is rotated ventrally into a slightly anterior orientation in preparation for oviposition. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

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A new species of the genus Ronderosia Cigliano 1997 is described. Color illustrations of the female and male, drawings of female and male external genitalia as well as drawings of its phallic structures and photographs of the chromosomes are included.

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Descrevemos o comportamento reprodutivo de Adelosgryllus rubricephalus Mesa & Zefa, 2004. em observações realizadas em laboratório verificamos a seguinte seqüência no comportamento de acasalamento: (1) reconhecimento sexual por antenação; (2) corte, em que o macho volta seu abdômen em direção à fêmea, vibra as antenas médio-lateralmente, treme o corpo ântero-posteriormente e estridula intermitentemente, enquanto a fêmea receptiva toca a ponta do abdômen, os cercos e os fêmures posteriores do macho, com seus palpos ou tarsos anteriores; o macho então fica imóvel por alguns segundos, expõe o espermatóforo e ambos retomam a seqüência comportamental descrita acima; (3) cópula: o macho coloca-se sob a fêmea, com suas tégminas inclinadas para frente, anexa sua genitália à dela e promove a transferência do esperma; a fêmea desce de cima do macho e ocorre brevemente a posição end-to-end durante a separação do casal; (4) pós-cópula: não há comportamento de guarda; o macho retém o espermatóforo e o ingere. Quantificamos o intervalo de tempo das principais etapas do acasalamento e discutimos suas possíveis implicações no comportamento observado.

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A anatomia dos órgãos internos do aparelho reprodutor de machos (ARM) adultos e pupas foi comparada em 51 espécies de abelhas, incluindo representantes de seis famílias. Foram obtidos quatro tipos diferentes de ARM. O tipo I está presente em machos das famílias mais basais (Colletidae, Andrenidae e Halictidae) e é caracterizado por três túbulos seminíferos por testículo, o qual é quase totalmente envolvido pela membrana escrotal. O tipo II é um tipo intermediário entre os tipos I e III e está presente em Mellitidae e Megachilidae, como também em alguns Apidae estudados, sendo caracterizado por possuir dutos deferentes pós-vesiculares fora da membrana escrotal e possuir três ou quatro túbulos seminíferos por testículo, exceto Apis mellifera L., a qual possui secundariamente um número aumentado de túbulos. O tipo III foi achado somente nos Apidae estudados e é caracterizado por apresentar os testículos e dutos genitais (exceto o duto deferente pós-vesicular) encapsulados separadamente, as glândulas acessórias são bem desenvolvidas e o duto ejaculador é calibroso, apresentando fissuras em sua parede externa, as quais podem ocorrer também no tipo II. O tipo IV está presente exclusivamente na tribo Meliponini e é caracterizado pela ausência de glândulas acessórias.

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Two Brazilian populations of Psammolestes tertius (Ceara and Minas Gerais) collected from thornbird nests (Furnariidae) were compared by male genital morphology, morphametry, isoenzymes, and random amplified polymorphic DNA (RAPD). Merle genitalia showed no difference between the populations. In contrast, morphometry, isoenzyme, and RAPD clearly distinguished the two populations. Possible mechanisms of dispersal and the origin of Psammolestes are discussed.

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Comparing introduced to ancestral populations within a phylogeographical context is crucial in any study aiming to understand the ecological genetics of an invasive species. Zaprionus indianus is a cosmopolitan drosophilid that has recently succeeded to expand its geographical range upon three continents (Africa, Asia and the Americas). We studied the distribution of mitochondrial DNA (mtDNA) haplotypes for two genes (CO-I and CO-II) among 23 geographical populations. mtDNA revealed the presence of two well-supported phylogenetic lineages (phylads), with bootstrap value of 100%. Phylad I included three African populations, reinforcing the African-origin hypothesis of the species. Within phylad II, a distinct phylogeographical pattern was discovered: Atlantic populations (from the Americas and Madeira) were closer to the ancestral African populations than to Eastern ones (from Madagascar, Middle East and India). This means that during its passage from endemism to cosmopolitanism, Z. indianus exhibited two independent radiations, the older (the Eastern) to the East, and the younger (the Atlantic) to the West. Discriminant function analysis using 13 morphometrical characters was also able to discriminate between the two molecular phylads (93.34 +/- 1.67%), although detailed morphological analysis of male genitalia using scanning electron microscopy showed no significant differences. Finally, crossing experiments revealed the presence of reproductive barrier between populations from the two phylads, and further between populations within phylad I. Hence, a bona species status was assigned to two new, cryptic species: Zaprionus africanus and Zaprionus gabonicus, and both were encompassed along with Z. indianus and Zaprionus megalorchis into the indianus complex. The ecology of these two species reveals that they are forest dwellers, which explains their restricted endemic distribution, in contrast to their relative cosmopolitan Z. indianus, known to be a human-commensal. Our results reconfirm the great utility of mtDNA at both inter- and intraspecific analyses within the frame of an integrated taxonomical project.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Ceraeochrysa Adams is the largest genus in Chrysopini with 62 valid species distributed in the New World. The taxonomy of this group is complex and largely based on male genitalic characters. There are still serious complications, especially with the species that have been described solely from female specimens. The male of C. montoyana (Navas, 1913), unknown previously, is herein described for the first time, and compared with its closest relative, C. claveri (Navas, 1911). Ceraeochrysa acutipuppis Adams & Penny, 1985 is designated as a junior synonym of C. fairchildi (Banks, 1946) based on the evidence that both species share external morphological features uncommon in other species of the genus. The species C. claveri, C. fairchildi and C. montoyana are recorded from Venezuela for the first time. External morphology and genitalia of these insects are described and illustrated.

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Titanochrysa Sosa & Freitas is a new genus of Neotropical Chrysopini (Chrysopidae: Chrysopinae) recorded from Costa Rica, Venezuela and Brazil. Titanochrysa gen. nov. shares several external and genitalic characters with Ceraeochrysa Adams, 1982; Chrysopodes Navas, 1913; Cryptochrysa Freitas & Penny, 2000; Parachrysopiella Brooks & Barnard, 1990 and Ungla Navas 1914. It may be distinguished from those genera by its very long sternite 8+9, sternites 2-8 usually with microtholi, male genitalia with the dorsal surface of the arcessus striated, gonosaccus well-developed, bearing elongate gonosetae and microsetae, and a spoon-like gonapsis. Herein, Titanochrysa circumfusa (Burmeister, 1939) [= Chrysopodes circumfusa (Burmeister)] comb. nov. and Titanochrysa pseudovaricosa (Penny) [= Ceraeochrysa pseudovaricosa Penny, 1998] comb. nov. were identified; Titanochrysa ferreirai Sosa & Freitas sp. nov. and Titanochrysa trespuntensis Sosa & Freitas sp. nov. were described. The external morphology, and male and female genitalia of all these species are described. Titanochrysa circumfusa (Burmeister, 1939) comb. nov. is recorded for the first time from Venezuela.

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Superovulation was induced in 15 Nelore cows with porcine follicle stimulating hormone (FSH-P) or pregnant mare serum gonadotropin (PMSG), and embryos were collected to compare the response of this breed of cattle to these hormones. FSH-P was given in 30-and 40-mg doses for 5 d as a single daily injection or fractionated into two daily injections. PMSG was given in doses of 1000 and 2000 IU. The animals were killed immediately after embryo collection and the ovaries and genitalia were examined clinically. PMSG proved to be more effective in inducing superovulation than FSH-P, probably because PMSG caused no stress since it was administered as a single dose. No differences were observed between the 30-and 40-mg dose of FSH-P or between the application as a single or fractionated dose. Differences did occur, however, between the number of ovulations and embryos obtained at each collection. On the basis of postmortem analysis, we concluded that lack of egg uptake by the infundibulum had occurred in cases of increased ovulation, with excessive increase in volume of the ovary. We also recommend using smaller doses of FSH-P and suggest that avoiding stress in handling is essential for a good response to hormonal stimulation by Zebu cattle. © 1986.

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In a group of 12 Pitangueiras breed heifers exhibiting a high return rate to service, three were noted to be carriers of the 1 29 translocation. One of the heifers exhibited trisomy for the X-chromosome in addition to the 1 29 translocation. The appearance and external genitalia of the 1 29 T; trisomy X heifer were not altered, although on rectal examination the internal genitalia, including the ovaries, appeared similar to that of a prepubertal heifer. © 1987.

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This study investigated the role of the early lactation milk (ELM) on the male reproductive performance and the participation of GnRH on this effect in Wistar rats. Newborn males were divided into three experimental groups: 1) ELM-deprived pups, 2) ELM-deprived pups treated with exogenous GnRH 1, 7, 25, and 31 h after birth, and 3) non-ELM-deprived and without exogenous GnRH. In relation to the other two groups, the ELM-deprived male rats exhibited as adults: reduced fertility, decreased weight of both vas deferens and seminal vesicle, and reduced levels of fructose in the seminal vesicle and prostate gland. We suggest that the intake of ELM during the neonatal period is important to the later sexual development of rats, and that GnRH is somehow involved in such an effect.