988 resultados para Paedomorphic characters
Resumo:
Studying thirteen speciemens of the genus Ormia Robineau-Desvoidy, 1830, and one of Euphasiopteryx Towsend, 1915, the author describes six new species: Ormia mendesi sp. n., Ormia lenkoi sp. n., Ormia carreirai sp. n., Ormia crespoi sp. n., Ormia wygodzinskyi sp. n., and Euphasiopteryx lenti sp. n. from Brasil and Argentina. The importance of the ocelli as a generic character, as stated by Towsend (1936) is discussed based on the absence of ocelli in Ormia mendesi sp. n. and Ormia crespoi sp. n. and its presence in Euphasiopteryx lenti sp. n. A key for the determination of Ormia species is presented based chiefly on the males external morphological characters.
Resumo:
A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.
Resumo:
Mice infected with 30 cercariae of Schistosoma mansoni developed portal and septal fibrosis due to the massive and concentrated deposition of eggs in the periportal areas which occurred following the 16th week after infection. The lesion resembled pipe-stem fibrosis seen in human hepatosplenic schistosomiasis in the following characters: portal fibrosis interconnecting portal spaces as well as portal spaces and central canals; portal inflammation; periovular granulomas; vascular obstruction and telangiectasia. The liver parenchyma maintained its normal architecture. Vascular injection techniques with Indian ink and vinylite revealed that the portal system developed numerous dilated collateral venules coming from the large and medium-sized portal branches, about 10 weeks after schistosome infection. The lodging of schistosome eggs into these collaterals resulted in granulomatous inflammation and fibrosis along all the portal tracts, thus forming the pipe-stem lesion. Although not readily demonstrable grossly, the pipe-stem fibrosis of murine schistosomiasis has many similarities with the human lesion and can be considered to have the same basic pathogenesis.
Resumo:
Aedes (Ochlerotatu) rhyacophilus Costa Lima i resurrected from the synonymy with Aedes (Ochlerotatus) scapularis (Rondani). Lectotype and paralectotypes are designated Larval, pupal and both sexes of adult stages are redescribed and illustrated. Bionomics include a picture of a brreding place. Diagnostic characters for distinguishing rhyacophilus from other species of the Scapularis Group are provided. Some data about known distribution are presented.
Resumo:
Megalobulimus lopesi, a new species of megalobulimidae, is described with basis on conchyological and anatomical characters. It is very close to M. grandis (Martens, 1885), the largest species of land gastropds of Brazil, from Sao Sebastiao Island (23º49'S 45º20'W).
Resumo:
In order to stablish new taxonomic characters for the genus Opisthcidius a detailed comparative study of the male external genitalia was performed in O. rubropictus (H. Shaeffer, 1848), the type species, and O. pertinax (Breddin, 1903), mantioned as predators of triatomines. The most representative phallic structures were: the median process of pygophore, the phallosoma struts and the vesica process.
Resumo:
This paper extends previous research and discussion on the use of multivariate continuous data, which are about to become more prevalent in forensic science. As an illustrative example, attention is drawn here on the area of comparative handwriting examinations. Multivariate continuous data can be obtained in this field by analysing the contour shape of loop characters through Fourier analysis. This methodology, based on existing research in this area, allows one describe in detail the morphology of character contours throughout a set of variables. This paper uses data collected from female and male writers to conduct a comparative analysis of likelihood ratio based evidence assessment procedures in both, evaluative and investigative proceedings. While the use of likelihood ratios in the former situation is now rather well established (typically, in order to discriminate between propositions of authorship of a given individual versus another, unknown individual), focus on the investigative setting still remains rather beyond considerations in practice. This paper seeks to highlight that investigative settings, too, can represent an area of application for which the likelihood ratio can offer a logical support. As an example, the inference of gender of the writer of an incriminated handwritten text is forwarded, analysed and discussed in this paper. The more general viewpoint according to which likelihood ratio analyses can be helpful for investigative proceedings is supported here through various simulations. These offer a characterisation of the robustness of the proposed likelihood ratio methodology.
Resumo:
It is described Trypanosoma nupelianus sp. n. parasitizing Rhinelepis aspera taken from Paraná river (Itaipu reservoir, Brazil). Morphometric characters such as body length, width of the body and nucleus dimensions show that T. nupelianus sp. n. is different from other trypanosomes described for fishes from tropical regions.
Resumo:
The heat- and odour-producing genus Arum (Araceae) has interested scientists for centuries. This long-term interest has allowed a deep knowledge of some complex processes, such as the physiology and dynamics of its characteristic lure-and-trap pollination system, to be built up. However, mainly because of its large distributional range and high degree of morphological variation, species' limits and relationships are still under discussion. Today, the genus comprises 28 species subdivided into two subgenera, two sections and six subsections. In this study, the phylogeny of the genus is inferred on the basis of four plastid regions, and the evolution of several morphological characters is investigated. Our phylogenetic hypothesis is not in agreement with the current infrageneric classification of the genus and challenges the monophyly of several species. This demonstrates the need for a new infrageneric classification based on characters reflecting the evolution of this enigmatic genus. To investigate the biogeography of Arum deeply, further spatiotemporal analyses were performed, addressing the importance of the Mediterranean basin in the diversification of Arum. Our results suggest that its centre of origin was the European-Aegean region, and that major diversification happened during the last 10 Myr.
Resumo:
Gastromermis cordobensis n. sp (Nematoda: Mermithidae) a parasite of larvae of the blackfly Simulium lahillei Paterson & Shannon (Diptera: Simuliidae) in Argentina, is described. Diagnostic characters of this species include a mouth ventrlly shifted; six cephalic papillae; eigh hypodermal chords; small and pear shaped amphids; a long and S-shaped vagina; a singl spicule, which is long, has non-uniform walls, and a tip with sculpture; three rows of genital papillae, the middle one with 18 pre-anal and 10 post-anal papillae, the lateral rows have 36 papillae each; oval eggs; and post-parasitic juveniles with long thin tails. Pre-parasitic and parasitic juveniles are included in the description.
Resumo:
Two samples of Biomphalaria prona (Martens, 1873) from Lake Valencia (type locality) and seven from other Venezuelan localities were studied morphologically (shell and reproductive system) and biochemically (allozyme electrophoresis). In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacustrine populations refered to Biomphalaria havanensis (Pfeiffer, 1839) by several authors correspond in shell characters to an extreme variant of B. prona from the Lake and really belong to the last*mentioned species. They may be regarded as the result of a process of directional selection favoring a shell phenotype other than those making up the modal class in the Lake.
Resumo:
Several cytogenetic traits were tested a species diagnostic characters on five triatomine species: Rhodnius pictipes, R. nasutus, R. robustus, Triatoma matogrossensis and T. pseudomaculata. Four of them are described for the first time. The detailed analysis of the meiotic process and the application of C-banding allowed us to identify seven cytogenetic characters wich result useful to characterize and differentiate triatomine species.
Resumo:
Treball de recerca realitzat per un alumne d'ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l'any 2009. 'El Giravolt de la Família Robafaves' és un treball de recerca que engloba tota la història del fet geganter a Mataró des dels seus orígens fins a l'actualitat. Es tracta d'una activitat amb una dimensió cultural, folklòrica i històrica que ha servit per donar respostes a molts dels interrogants promulgats abans de dur a terme aquest projecte. Aquesta família de Gegants ha estat víctima de molts dels entrebancs vigents al llarg de la història així com guerres, revoltes, dictadures, etc. De manera que s'ha pogut comprovar com la política interior i exterior ha afectat a la Família Robafaves d'una manera directa. S'ha fet una investigació a través de les revistes publicades durant la transició democràtica. També cal dir que, s'ha tingut el recolzament d'entrevistes fetes a persones puntals en la història dels Gegants com ara geganters, Caps de Colla, la primera gegantera de la Família Robafaves, etc. Per poder corroborar la base teòrica i documental d'aquest treball s'ha fet un estudi estadístic de la significació social de la Festa Major de Mataró per poder valorar en quina situació es troba actualment. Així doncs, s'ha pogut valorar la influència i importància que tenen els Gegants per Mataró.
Resumo:
A description is given of Madathamugadia wanjii n. sp., a Splendidofilariinae parasite of the gecko Ptyodactylus hasselquistii, on the west bank of the River Jordan and of its life cycle in Phlebotomus duboscqi. The new species is close to M. ivaschkini (Annaev, 1976) n. comb., of Turkmenistan, wich is also transmitted by sandflies (Reznik, 1982). The genus Madathamugadia is now comprised of four species, two from Madagascar and two from the Mediterranean sub-region; it differs from the genus Thamugadia by the presence of a double row of papillae anterior to the cloaca of the male. The larval characters of Splendidofilarinae of lizards confirm the affinity of these parasites to the Splendidofilarinae of birds (Chandlerella and Splendidofilaria); the first group could have arisen from the second by "captures" wich could have occurred in several places.
Resumo:
The morphological comparative study of the phallus organs, of both species, shown five structures wich may be used as taxonomic characters. They are: parameres (Pa), median process pygophore (PrP), basal plate (EPbi), gonopore (PrG) and endosoma process (PrEn).