ABSTRACT The golden mussel, Limnoperna fortunei, is among the most devastating invasive species in freshwater habitats worldwide, leading to severe environmental disturbances and economic losses. Therefore, management efforts would be greatly improved by methods that efficiently detect and quantify the abundance of the golden mussel in freshwater habitats, particularly in early stages of colonization. In this study, we describe a highly-sensitive real-time PCR assay targeting a 100-bp region of the COI mitochondrial gene of the golden mussel. The method was able to detect as little as 0.225 pg of target DNA. This assay represents an important contribution to surveillance methods, as well as to optimize field measures to contain and manage populations of the golden mussel in its introduced range.

Exon-primed intron-crossing (EPIC) markers as a tool for ant phylogeography. Due to their local abundance, diversity of adaptations and worldwide distribution, ants are a classic example of adaptive radiation. Despite this evolutionary and ecological importance, phylogeographical studies on ants have relied largely on mitochondrial markers. In this study we design and test exon-primed intron-crossing (EPIC) markers, which can be widely used to uncover ant intraspecific variation. Candidate markers were obtained through screening the available ant genomes for unlinked conserved exonic regions interspersed with introns. A subset of 15 markers was tested in vitro and showed successful amplification in several phylogenetically distant ant species. These markers represent an important step forward in ant phylogeography and population genetics, allowing for more extensive characterization of variation in ant nuclear DNA without the need to develop species-specific markers.

Hair snares have been used in North and Central America for a long time in assessment and monitoring studies of several mammalian species. This method can provide a cheap, suitable, and efficient way to monitor mammals because it combines characteristics that are not present in most alternative techniques. However, despite their usefulness, hair snares are rarely used in other parts of the world. The aim of our study was to evaluate the effectiveness of hair snares and three scent lures (cinnamon, catnip, and vanilla) in the detection of felids in one of the largest remnants of the Brazilian Atlantic Forest. We performed tests with six captive felid species - Panthera onca (Linnaeus, 1758), Leopardus pardalis (Linnaeus, 1758), L. tigrinus (Schreber, 1775), L. wiedii (Schinz, 1821), Puma concolor (Linnaeus, 1771), and P. yagouaroundi (É. Geoffroy Saint-Hilaire, 1803) - to examine their responses to the attractants, and to correlate those with lure efficiency in the field. The field tests were conducted at the Parque Estadual Pico do Marumbi, state of Paraná, Brazil. Hair traps were placed on seven transects. There were equal numbers of traps with each scent lure, for a total of 1,551 trap-days. In captivity, vanilla provided the greatest response, yet no felids were detected in the field with any of the tested lures, although other species were recorded. Based on the sampling of non-target species, and the comparison with similar studies elsewhere, this study points to a possible caveat of this method when rare species or small populations are concerned. Meanwhile, we believe that improved hair snares could provide important results with several species in the location tested and others.

The decapod Grapsus grapsus is commonly found on oceanic islands of the Pacific and Atlantic coasts of the Americas. In this study, a simple, quick and reliable method for detecting its larvae in plankton samples is described, which makes it ideal for large-scale studies of larval dispersal patterns in the species.

Although lethargic crab disease (LCD) is causing massive mortalities in populations of the mangrove crab Ucides cordatus of Northeastern Brazil, the identity of its etiological agent was hitherto unknown. In this study we provide robust evidence suggesting that LCD is caused by an anamorph Ascomycota (Fungi). We examined specimens of U. cordatus collected from stocks affected by LCD. Histological and TEM methods detected the presence of hyphae, conidia, and condiophores in several host tissues. Moreover, the abundance of fungal stages is negatively associated with crab health. Finally, DNA was isolated from the fungus and a region of its 18S ribosomal gene was sequenced. Phylogenetic analyses not only confirm the diagnosis of the LCD fungus in crab tissues as an ascomycete, but also suggest a close relationship with members of the subphylum Pezizomycotina.

Nectários extraflorais (NEFs) são glândulas de néctar não relacionadas com o processo de polinização da planta e que podem ocorrer virtualmente em todas as estruturas vegetativas e reprodutivas de angiospermas. Estudos recentes revelaram que NEFs ocorrem em diversas espécies de arbustos e árvores dos cerrados brasileiros. Plantas portadores destas glândulas são visitadas de dia e de noite por diversas espécies de formigas nectarívoras do cerrado. Nesta revisão apresentamos os dados obtidos nos últimos 15 anos sobre a interação entre formigas e plantas com NEFs em vegetação de cerrado. Estudos experimentais no campo indicam que as formigas visitantes de NEFs podem predar ou injuriar insetos herbívoros que encontram sobre as plantas, reduzindo significativamente as taxas de herbivoria sobre as folhas, botões ou flores. Em resposta, algumas espécies de herbívoros desenvolveram vários mecanismos para evitar o ataque das formigas sobre suas plantas hospedeiras. Os benefícios oferecidos às plantas pelas formigas visitantes, entretanto, podem variar com a agressividade da espécie de formiga, com as estratégias defensivas apresentadas pelos insetos herbívoros, bem como com a espécie de planta. Os resultados obtidos para diferentes espécies de plantas de cerrado são discutidos, indicando áreas promissoras para estudos experimentais futuros.

Extrafloral nectaries (EFNs) are nectar-secreting glands not directly involved with pollination which may occur on virtually all above-ground plant parts of angiosperms. Recent studies revealed that such glands are widely distributed amongst the woody flora of the Brazilian cerrados. Plants bearing EFNs are visited day and night by a diverse assemblage of nectarivorous ants. In this review we present the data gathered during the past 15 years on the interaction between ants and EFN-bearing plants in cerrado vegetation. Field experiments indicate that ants visiting EFNs may prey or attack insect herbivores on the plant foliage, significantly reducing herbivore damage to leaves, buds or flowers. As a response, some herbivore species have developed an array of mechanisms to circumvent the ants' deterring capacities on their host plants. Ant-derived benefits to plants, however, may vary with the species of visiting ant, with the defensive tactics of the associated herbivores, as well as with the plant species. We discuss the results obtained for different cerrado plant species, and suggest some promising topics for future experimental investigation.