Sibling Species

Genes involved in the reproductive isolation are particularly useful as molecular markers in speciation studies. Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae), a putative species complex, is a vector of visceral leishmaniasis in Latin America. We isolated from this species a fragment homologous to cacophony, a Drosophila gene that encodes features of the lovesong, an acoustic signal that is important in the sexual isolation of closely related species and known to vary considerably among L. longipalpis putative siblings species. Using an intron of the sandfly cacophony as a marker, we analyzed the molecular variation and sequence divergence among five populations of L. longipalpis from Brazil, three allopatric (Jacobina, Lapinha and Natal) and two putative sympatric sibling species from the locality of Sobral. A high level of polymorphism was found and analysis of the data indicates that very little gene flow is occurring among the populations of Jacobina, Lapinha, and Natal. A high level of differentiation was also observed between the two putative sympatric species of Sobral, one of which seems to be the same sibling species found in Natal, while the other is somewhat more related to Jacobina and Lapinha. However, the amount of estimated gene flow among the Sobral siblings is about seven times higher than the previously estimated for period, another lovesong gene, perhaps indicating that introgression might be affecting cacophony more than period. The results suggest that L. longipalpis is not a single species in Brazil, but it is yet not clear whether the different populations studied deserve species status rather than representing an incipient speciation process.

The specifics of distribution and status of local mammal species of sibling complexes demonstrating signs of significant either current or recent range dynamics are considered. These species complexes comprise pairs of sibling and morphologically close species, which until recently have not been unambiguously distinguished, thus it was impossible to analyse their range dynamics. However, range dynamics of this group of species is of great interest since it determines the emergence of high species diversity and realisation of mechanisms of compact organisation of communities that include close species. The amassed by today knowledge on distribution of species and the identification criteria developed for some of those species based on collection specimens allow to analyse changes in their distribution ranges. Such data in most cases allow to perform reconstructions and to develop respective hypotheses on dispersal routes of species in the region. In total, 9 species complexes were considered. Ranges of species that by direct or indirect evidence demonstrate changes in the area of their distribution and in the same time change the system of interspecific spatial relationships within each group are described. These spatial relationships can vary from allopatry to marginal or significant sympatry. Such complexes of "small" species were described in the composition of former "large" polytypic species with signs of invasions or expansions of their components among bats (Plecotus auritus + austriacus, Pipistrellus pipistrellus + pygmaeus, Eptesicus serotinus + lobatus) and rodents (Spermophilus suslicus + odes-sanus, Microtus arvalis + obscurus, Mus musculus + spicilegus). Similar but less expressed signs can be also traced in some other groups (Spalax zemni + arenarius, Sylvaemus sylvaticus + whiterbyi, Capreolus capreo-lus + pygargus). Distribution maps for all these species complexes are presented with reconstructions of possible directions of their dispersal through the territory of the region (Ukraine and adjacent countries). Zones of prochoresis, where these species most likely were absent in the recent past, are determined and analysed. The time and pace of expansion of "small" species in the region are estimated. The significance of morphological criteria of species and the possibilities of revision of old collection specimens to analyse temporal changes of biota are shown as well as the importance of cartographic data for such analysis. By using data from revisions, it is possible to estimate geographical tendencies and velocity of expansion for many species, including those that represent groups of morphologically close or sibling species. K e y w o r d s : sibling species, mammals, range dynamics, biological invasions, biogeography, Ukraine.

The two sibling mouse-eared bats, Myotis myotis and M. blythii, cope with similar orientation tasks, but separate their trophic niche by hunting in species-specific foraging microhabitats. Previous work has shown that both species rely largely on passive listening to detect and glean ...

Multimammate rats (genus Mastomys) are abundant in many regions throughout sub-Saharan Africa, and are of high economical and sanitary importance as agricultural pests as well as reservoir/vectors of human diseases. In pest management and in epidemiological studies, unequivocal species identification of individuals collected in the field is crucial. However, the discrimination among most of the Mastomys species is often difficult,

Background Mosquito sampling methods are essential for monitoring and evaluating malaria vector control interventions. In urban Dar es Salaam, human landing catch (HLC) is the only method sufficiently sensitive for monitoring malaria-transmitting Anopheles. HLC is labour intensive, cumbersome, hazardous, and requires such intense supervision that is difficulty to sustain on large scales. Methods Novel tent traps were developed as alternatives to HLC. The Furvela tent, designed in Mozambique, incorporates a CDC Light trap (LT) components, while two others from Ifakara, Tanzania (designs A and B) require no electricity or moving parts. Their sensitivity for sampling malaria vectors was compared with LT and HLC over a wide range of vector abundances in rural and urban settings in Tanzania, with endophagic and exophagic populations, respectively, using randomised Latin-square and cross- over experimental designs. Results The sensitivity of LTs was greater than HLC while the opposite was true of Ifakara tent traps (crude mean catch of An. gambiae sensu lato relative to HLC = 0.28, 0.65 and 1.30 for designs A, B and LT in a rural setting and 0.32 for design B in an urban setting). However, Ifakara B catches correlated far better to HLC (r2 = 0.73, P < 0.001) than any other method tested (r2 = 0.04, P = 0.426 and r2 = 0.19, P = 0.006 for Ifakara A and LTs respectively). Only Ifakara B in a rural setting with high vector density exhibited constant sampling efficiency relative to HLC. The relative sensitivity of Ifakara B increased as vector densities decreased in the urban setting and exceeded that of HLC at the lowest densities. None of the tent traps differed from HLC in terms of the proportions of parous mosquitoes (P ≥ 0.849) or An. gambiae s.l. sibling species (P ≥ 0.280) they sampled but both Ifakara A and B designs failed to reduce the proportion of blood-fed mosquitoes caught (Odds ratio [95% Confidence Interval] = 1.6 [1.2, 2.1] and 1.0 [0.8, 1.2], P = 0.002 and 0.998, respectively), probably because of operator exposure while emptying the trap each morning. Conclusion The Ifakara B trap may have potential for monitoring and evaluating a variety of endophagic and exophagic Afrotropical malaria vectors, particularly at low but epidemiologically relevant population densities. However, operator exposure to mosquito bites remains a concern so additional modifications or protective measures will be required before this design can be considered for widespread, routine use.

The genus Cyclope Risso, 1826 (family Nassariidae) has appeared in the fossil record since the Pliocene. Although it is still found today, the teleoconch morphology has never undergone modification, despite the fact that the protoconch morphologies of fossils (multispiral) and ...