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1.
Mem. Inst. Oswaldo Cruz ; 108(supl.1): 92-99, 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-697836

RESUMEN

Rhodnius barretti , a new triatomine species, is described based on adult specimens collected in rainforest environments within the Napo ecoregion of western Amazonia (Colombia and Ecuador). R. barretti resembles Rhodnius robustus s.l. , but mitochondrial cytochrome b gene sequences reveal that it is a strongly divergent member of the “robustus lineage”, i.e., basal to the clade encompassing Rhodnius nasutus , Rhodnius neglectus , Rhodnius prolixus and five members of the R. robustus species complex. Morphometric analyses also reveal consistent divergence from R. robustus s.l. , including head and, as previously shown, wing shape and the length ratios of some anatomical structures. R. barretti occurs, often at high densities, in Attalea butyracea and Oenocarpus bataua palms. It is strikingly aggressive and adults may invade houses flying from peridomestic palms. R. barretti must therefore be regarded as a potential Trypanosoma cruzi vector in the Napo ecoregion, where Chagas disease is endemic.


Asunto(s)
Animales , Enfermedad de Chagas/transmisión , Enfermedades Endémicas , Bosque Lluvioso , Rhodnius/anatomía & histología , Rhodnius/clasificación , Arecaceae , Teorema de Bayes , Colombia , Enfermedad de Chagas/epidemiología , Citocromos b/genética , Ecología , Ecosistema , Ecuador , Filogenia , Análisis de Secuencia , Especificidad de la Especie , Triatominae/clasificación
2.
Mem. Inst. Oswaldo Cruz ; 97(8): 1191-1195, Dec. 15, 2002. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-326336

RESUMEN

The most important vectors of human Plasmodium in the neotropics belong to the subgenus Nyssorhynchus. These species are generally sympatric in terms of their geographical distributions. Some are difficult to identify based solely on examination of adult females using the available morphological keys, in these cases examination of immature stages and male genitalia is required to make correct determinations. However, in epidemiological studies it is necessary to identify the species of adult females which are found near humans, i.e. in studies of malaria transmission or evaluation of control measures. The purpose of the present study was to evaluate the discrimination of adult females of different species of Nyssorhynchus isolated mainly from Southern Colombia (department of Putumayo), using morphometric analysis. Adult females were obtained after rearing larvae collected in natural breeding places and from the progeny of females collected on humans. The morphological characteristics of the immature stages allowed the identification of four species of the subgroup Oswaldoi from Southern Colombia: Anopheles rangeli Gabaldon, Cova Garcia & Lopez, An. oswaldoi (Peryassu), An. benarrochi Gabaldon, Cova Garcia & Lopez and An. triannulatus (Neiva & Pinto). The species An. nuneztovari (Gabaldon) from the Northwest of Colombia was included for comparison. Morphometric analysis allowed differentiation of the females of all species to a confidence level approaching 90 percent using principal components analysis of 10 wing and leg variables, followed by canonical variate analysis of the first four principal components. We conclude that morphometrics may represent a useful taxonomic tool for this group and that its use should be further studied


Asunto(s)
Animales , Humanos , Femenino , Anopheles , Análisis por Conglomerados , Colombia , Intervalos de Confianza , Análisis Multivariante , Análisis de Componente Principal
3.
Mem. Inst. Oswaldo Cruz ; 97(5): 667-673, July 2002. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-321192

RESUMEN

The finding of Panstrongylus geniculatus nymphs inside a house in northeastern Antioquia, Colombia, and the reports related to their increasing presence in homes suggest the need for surveillance methods for monitoring the invasion processes. We analyzed the morphological differences between a wild population and its laboratory descendants, using the techniques of geometric morphometry, with the idea that such differences might parallel those between sylvatic and synanthropic populations. The analyses over five generations showed differences in size but not in shape. Head size and wing size were both reduced from sylvatic to laboratory populations, but the decrease in head size occurred only up to the second generation while the decrease in wing size proceeded up to the fifth generation. In contrast, although a decrease in sexual size dimorphism has been proposed as a marker of colonization in human dwellings, we did not detect any significant loss of dimorphism between sexes of P. geniculatus over the five generations studied. We conclude that size changes may have a physiological origin in response to a change of ecotopes, but more than five generations may be required for the expression of permanent morphological markers of human dwellings colonization


Asunto(s)
Animales , Masculino , Femenino , Panstrongylus , Constitución Corporal , Distribución de Chi-Cuadrado , Cabeza , Laboratorios , Panstrongylus , Análisis de Componente Principal , Caracteres Sexuales , Alas de Animales/anatomía & histología
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