Species diversity in vertical, horizontal, and temporal dimensions of a fruit-feeding butterfly community in an Ecuadorian rainforest

To test the hypotheses that fruit-feeding nymphalid butterflies are randomly distributed in space and time, a community of fruit-feeding nymphalid butterflies was sampled at monthly intervals for one year by trapping 6690 individuals of 130 species in the canopy and understory of four forest habitats: primary, higraded, secondary, and edge. The overall species abundance distribution was well described by a lognormal distribution. Total species diversity (γ-diversity) was partitioned into additive components within and among community subdivisions (α-diversity and β-diversity) in vertical, horizontal and temporal dimensions. Although community subdivisions showed high similarity (1 —β-diversity/γ-diversity), significant β-diversity existed in each dimension. Individual abundance and observed species richness was lower in the canopy than in the understory. However, rarefaction analysis and species accumulation curves revealed that canopy had higher species richness than understory. Observed species richness was roughly equal in all habitats, but individual abundance was much greater in edge, largely due to a single, specialist species. Rarefaction analysis and species accumulation curves showed that edge had significantly lower species richness than all other habitats. Samples from a single habitat, height and time contained only a small fraction of the total community species richness. This study demonstrates the feasibility, and necessity, of large-scale, long-term sampling in multiple dimensions for accurately measuring species richness and diversity in tropical forest communities. We discuss the importance of such studies in conservation biology.     

Seasonal cycles of diversity and similarity in a Central American rainforest butterfly community

Despite the importance of understanding the effects of tropical seasonality on ecological diversity, few studies have investigated the influence of environmental factors on seasonal community composition, and even fewer use standardized sampling and robust analytical methods that are directly comparable. Our 104 months of sampling in Costa Rican lowland rainforest yielded 12 757 individuals of 106 fruit‐feeding butterfly species demonstrated biannual cycles in species diversity, but community similarity showed an annual cycle that peaked in the driest months. We found that community diversity and similarity did not decline with increasing time lag, which we attribute to lack of long‐term changes in species abundances. Our findings differ from a similar study in Ecuador, where cycles in weather and community diversity were annual. Long‐term intensive monitoring and robust statistical analysis of changes in community composition in relation to environmental factors can help to elucidate the dynamics of communities, and their response to climate change.     

Pleustonic communities with Lemnaceae in South America

Abstract. Ca. 360 relevés of pleustonic vegetation were recorded in South America between 1983 and 1996.245 relevés, containing three or more pleustonic species, were classified according to the methods of Braun-Blanquet. Within the class Lemnetea (minoris) the following two orders with alliances (All.) and associations (Ass.) can be distinguished: 1. Lemnetalia gibbae   All. Azollo filiculoides-Lemnion gibbae Ass. Lemno minutae-Lemnetum gibbae Azollo filiculoides-Wolffielletum oblongae 2. Lemnetalia aequinoctialis   All. Salvinio minimae-Lemnion minutae Ass. Lemno minutae-Wolffielletum lingulatae   All. Salvinio minimae-Lemnion aequinoctialis     Ass. Lemno aequinoctialis-Wolffielletum lingulatae Lemno aequinoctialis-Wolffielletum welwitschii   All. Woljfio columbianae-Lemnion obscurae     Ass. Woljfio globosae-Lemnetum obscurae The occurrence of the four alliances is mostly dependent on climate and geographical situation. The usefulness of creating pleustonic unities is discussed.     

Movement and vertical stratification of fruit-feeding butterflies in a managed West African rainforest

We analysed movement parameters and vertical stratification in fruit-feeding butterflies between a control, a thinned and a plantation site within a West African rainforest. Overall, distances moved between traps were largest in the plantation. Movement parameters were generally largest in species feeding on early successional hostplants of gap and margin habitats. In these species, distances between recaptures were significantly shorter in the thinned compared to the control forest. Conversely, forest floor species feeding on climbers and understorey shrubs showed significantly larger movement in the thinned forest. Higher strata species also flew larger distances in the thinned understorey. Including higher strata samples, they were significantly less abundant in the thinned plot, although understorey sampling alone indicated the contrary. Comparing vertical distribution patterns between thinned and control sites indicated a disruption of vertical stratification after thinning. Canopy species seem to fly in the upper strata of the more closed-canopy control forest, whereas they descend more frequently in the forest opened by the thinning management. Understorey sampling might therefore lead to biased conclusions due to differences in vertical distribution between forest plots. This study showed that thinning can affect the restricted-range forest floor butterflies as well as the more widespread canopy butterfly fauna.     

A rapid diversification of rainforest trees (Guatteria; Annonaceae) following dispersal from Central into South America

Several recent studies have suggested that a substantial portion of today's plant diversity in the Neotropics has resulted from the dispersal of taxa into that region rather than vicariance, but more data are needed to substantiate this claim. Guatteria (Annonaceae) is, with 265 species, the third largest genus of Neotropical trees after Inga (Fabaceae) and Ocotea (Lauraceae), and its widespread distribution and frequent occurrence makes the genus an excellent model taxon to study diversification patterns. This study reconstructed the phylogeny of Guatteria and inferred three major biogeographical events in the history of the genus: (1) a trans-oceanic Miocene migration from Central into South America before the closing of the Isthmus of Panama; (2) a major diversification of the lineage within South America; and (3) several migrations of South American lineages back into Central America via the closed Panamanian land bridge. Therefore, Guatteria is not an Amazonian centred-genus sensu Gentry but a major Miocene diversification that followed its dispersal into South America. This study provides further evidence that migration into the Neotropics was an important factor in the historical assembly of its biodiversity. Furthermore, it is shown that phylogenetic patterns are comparable to those found in Ocotea and Inga and that a closer comparison of these genera is desirable.     

Digital dermatoglyphics in two Afro-American communities of Central America

The present report provides analytical data of digital dermatoglyphics on 150 subjects (79 males, 71 females) from Bluefields, Nicaragua and 146 (98 males, 48 females) from Livingston, Guatemala. They were classified as belonging to three sub-samples: Negroes (Bluefields) or Black-Caribs (Livingston), Ladinos and Creoles. However due to the very small size of some sub-samples, the findings, related to brief demographical and ethno-historical perspectives, were compared, for Pattern Intensity Index and Total Finger Ridge Count, with those of other human groups. Statistically significant differences occur between Negroes (Bluefields) and Black-Caribs (Livingston) but no sharp differences were found within the other sub-samples. Because the literature doesn't contain dermatoglyphic data for the Afro-American Communities spread over the Atlantic coast of Middle America, from Belize to Panama, and really few data have been collected regarding other anthropological observations, large gaps remain to be filled about these interesting inbreeding populations. It is right to remark that an investigation oriented to a population mixture study necessitates the collection of more dermatoglyphic data before the dermatoglyphic results can be properly evaluated.     

The lichen genus Physcia in Central and South America

Thirty-four species of the lichen genus Physcia (s. str.) in Central and South America are defined. Morphology, anatomy, chemistry, distribution, habitat, relation to other taxa and some evolutionary trends are discussed. A key to the species is presented. Eleven species are described as new; P. cinerea, P. convexella, P. coronifera, P. decorticata, P. kalbii, P. lobulata, P. lopezii, P. manuelii, P. rolfii, P. sinuosa , and P. tenuis. P. nubila is a new name for Heterodermia desertorum .     

Nitrification and nitrogen mineralization in a lowland rainforest succession in Costa Rica,Central America

Summary Nitrogen availability is a critical component of productivity in successional lowland rainforests, and nitrogen losses from a given system may largely depend on rates of nitrification in soils of the system. Two hypotheses were tested in a study of a 6-point secondary rainforest sere in the coastal lowlands of Costa Rica: that nitrification and N mineralization change in a directed fashion in lowland rainforest successions, and that nitrification is regulated by ammonium availability at all points along the sere. Nitrate and mineral N production were measured in short-term laboratory incubations of soils from different stages of secondary succession corresponding to 0, 3, 8, 16, 31 and 60 + years following disturbance. Results indicate that nitrification increases through the first 4 successional stages and then declines somewhat before leveling off. In soil from all sites, most of the N mineralized was nitrified, and added NH₄Cl strikingly stimulated net nitrate production. Added NaH₂PO₄, CaCO₃, and CaSO₄ did not stimulate net nitrate production or did not result in a greater proportion of nitrate than in controls. These results suggest that nitrification and N mineralization may tend to increase through secondary rainforest succession and that ammonium availability along the sere regulates rates of nitrification.     

Similarity but not equivalence: Ecological niche comparison between sandflies from the Pleistocene and future scenarios in Central and South America

Sandfly species (Diptera: Psychodidae) are suspected or proven vectors of Leishmania spp. in the American region. Understanding niche conservatism (NC) in insect vectors allows an understanding of constraints on adaptive responses, and thus implications for disease ecology. Therefore, in this study, the authors evaluated NC in three vector species of leishmaniasis (Lutzomyia gomezi, Psathyromyia shannoni and Pintomyia ovallesi) in Central and South America. For this, the authors performed niche identity and similarity testing through paired comparisons in ENMTools and niche overlap in Niche Analyst. The authors found that species niches were more similar to each other than if the points had been randomly extracted, and they also found extensive similarity between Pa. shannoni and Lu. gomezi niches and in Pa. shannoni niches over different timescales. The authors suggest Pa. shannoni as a priority species due to fundamental niche similarity with phylogenetically related species and also its extensive evolutionary history and ecological plasticity that could affect the emergence and resurgence of leishmaniasis in areas endemic by this vector.     

Feeding responses and food preferences in the tropical, fruit-feeding butterfly, Bicyclus anynana

In the tropical butterfly Bicyclus anynana (Nymphalidae) essential components of fitness (such as fecundity and longevity) depend to a large degree on exogenous adult-derived nutrients, particularly carbohydrates. We investigated which of the nutrients/compounds found in the adult diet act as feeding stimuli, and whether butterflies show preferences for particular nutrients or combinations. Only sugars and alcohols acted as feeding stimuli, the highest responses being found for sucrose, glucose, ethanol, butanol and propanol. Various other compounds (e.g. amino acids, acetic acid, vitamins, lipids, salts, and yeast) did not elicit any probing or feeding responses. Behavioural tests revealed a clear preference hierarchy for sugars (sucrose > glucose > fructose > maltose), but not for alcohols. Butterflies did not discriminate between sucrose solutions enriched with different nutrients and plain sucrose solutions, although they showed a preference for acetic acid and an aversion to salts and ascorbic acid when offered in combination with sucrose. Throughout, both sexes showed very similar patterns. We conclude that locating carbohydrate sources seems sufficient to cover all the butterflies’ nutritional needs, while alcohols function primarily as long range signals, guiding the butterflies to food sources. Thus, fruit-feeding butterflies, in contrast to nectar-feeding butterflies, appear not to have distinctive preferences for e.g. amino acids or salts, but do share a common primary preference for sucrose.     

Summer floods shape meadow butterfly communities in a floodplain nature reserve in Central Europe

How flooding regimes shape temperate-zone butterfly communities has received little attention. At the river Danube in eastern Austria, a levee has largely interrupted natural river dynamics since the late nineteenth century. Only a fraction of the floodplain area still experiences annual summer inundations after snow-melt in the Alps. We surveyed meadow butterfly communities on either side of the levee in a year with an unusually strong flood (2013), and in a season with a weak flood typical for the region (2012). Altogether we observed 67 butterfly species. Butterfly abundance and species richness were lower on meadows with stronger flood impact, but differences were modest. In contrast, species composition differed prominently relative to flooding regime and nectar availability. Grass-feeding species tended to be rarer on flooded meadows, while Brassicaceae-feeding species were more prevalent on nutrient-rich flood-prone meadows. Highly dispersive butterflies made up a larger share on flooded meadows, whereas highly philopatric species were relatively more common at sites with little or no inundation. These results indicate that summer inundations at the river Danube act as filters for the local species composition of butterflies on floodplain meadows. Local resource availability and the differential potential of species to re-colonize meadows after catastrophic floods are likely drivers of these differences. Effects of inundations were not consistently stronger in a year of a catastrophic flood than in a normal season. Butterfly communities on non-flooded meadows had a higher regional conservation value.     

Effects of larval starvation and adult diet-derived amino acids on reproduction in a fruit-feeding butterfly

Availability of adequate nutrition is among the most important factors affecting growth, development, and reproduction in animals. In holometabolous insects, diets and nutritional needs change between life stages, with larval storage, and adult feeding and reproduction being linked to one another. In several butterfly species, adult feeding is of fundamental importance to realize the full reproductive potential, primarily due to a prominent role of adult diet-derived carbohydrates. In contrast, the role of adult diet-derived amino acids is still under debate, despite the fact that butterflies were often found to preferentially feed on amino acid-rich substrates. Recently it was found that amino acids from adult income could compensate for adverse effects of larval food quality. In our study on the tropical butterfly Bicyclus anynana (Butler) (Lepidoptera: Nymphalidae), we used larval starvation to investigate corresponding effects on female reproductive output. Short periods of larval starvation prolonged development time and reduced larval survival, larval growth rate, pupal mass, and egg size. Regardless of the degree of larval starvation, access to amino acids in the adult diet increased egg size, whereas egg number remained largely unaffected. Thus, although there was some evidence for adult diet-derived amino acids being overall beneficial to reproduction, there was no indication that they can compensate for larval starvation.     

The importance of small scales to the fruit-feeding butterfly assemblages in a fragmented landscape

Nowadays 37% of Earth’s ice-free land is composed by fragments of natural habitats settled in anthropogenic biomes. Therefore, we have to improve our knowledge about distribution of organisms in remnants and to understand how the matrix affects these distributions. In this way, the present study aims to describe the structure of the butterfly assemblages and determined how richness and abundance are influenced by the scale of the surrounding vegetation. General linear models were used to investigate how the type and scale of vegetation cover within a radius of 100–2,000 m around the sampling point explained butterfly diversity. After sampling ten forest fragments we found 6,488 individuals of 73 species. For all clades tested null models explain the species richness at the fragments better than other models when we include the effect of butterfly abundance as a covariate. Abundance of Satyrini, Brassolini, and Biblidinae were best predicted by small scales (100–200 m), and large scales were more suited for Charaxinae. The presence of pasture best explains the abundance of all groups except Charaxinae, which was best explained by early-regrowth forest. The abundance of different species and groups are correlated with different kinds of vegetation cover. However, we demonstrate that small scales (100–200 m) are more effective at explaining the abundance of most butterflies. These results strongly suggest that efforts to preserve insect diversity in forest fragments should take in account the immediate surroundings of the fragment, and not only the regional landscape as a whole. In general, actions of people living near forest fragments are as important to fruit-feeding butterflies as large scale actions are, with the former being seldom specified in management plans or conservation policies.     

Effects of adult-derived carbohydrates, amino acids and micronutrients on female reproduction in a fruit-feeding butterfly

It is generally believed that butterflies (and other holometabolous insects) rely primarily on reserves accumulated during the larval stage for reproduction, whereas the carbohydrate-rich adult diet is thought to mainly cover energy requirements. In at least some species though, realization of the full reproductive potential is extensively affected by post-eclosion nutrition. While the importance of carbohydrates is fairly well understood, the role of adult-derived amino acids and micronutrients is controversial and largely unknown, respectively. We here focus on the effects of different adult diets on female reproduction in the tropical, fruit-feeding butterfly Bicyclus anynana (Nymphalidae). Carbohydrates were the most important adult-derived nutrients affecting reproduction. Adding amino acids, vitamins or minerals to sucrose-based solutions did not yield a reproductive output equivalent to that of fruit-fed females, which showed the highest performance throughout. This suggests that either not yet identified compounds of fruit substantially contribute to reproduction, or that resource congruence (the use of nutrient types in a specified ratio) rather than any specific nutrient component is of key importance. Apart from adult income, realized fecundity depended on egg size and longevity, with the former dominating when dietary quality was low, but the latter when quality was high. Thus, the egg size-number trade-off seems to be affected by female nutrition.     

Phylogenetic relationships among species of the genus Oligoryzomys (Rodentia,Cricetidae) from Central and South America

González‐Ittig, R. E., Salazar‐Bravo, J., Barquez, R. M. & Gardenal, C. N. (2010). Phylogenetic relationships among species of the genus Oligoryzomys (Rodentia, Cricetidae) from Central and South America. —Zoologica Scripta, 39, 511–526. The genus Oligoryzomys includes several species very similar in external morphology, which has resulted in a confusing specific taxonomy. Accurate species identification is particularly important because several species of Oligoryzomys act as natural hosts of hantaviruses affecting humans. Here, we assign specific status to individuals from a wide geographical area of Argentina and Chile using sequences of the mtDNA control region. We also compare cytochrome b sequences of 14 species recognized from Central and South America to infer the phylogenetic relationships within the genus. In addition, the results were analysed using available data on chromosome numbers, and the host–parasite relationships reported for the genus Hantavirus. We confirm the geographical distribution of Oligoryzomys longicaudatus (Argentina, Chile), Oligoryzomys nigripes (Argentina, Paraguay, Brazil), Oligoryzomys chacoensis (Argentina, Bolivia, Paraguay), Oligoryzomys fornesi (Argentina, Paraguay), Oligoryzomys destructor (Argentina, Bolivia) and Oligoryzomys microtis (Bolivia, Brazil). Oligoryzomys longicaudatus is strongly related to the Oligoryzomys flavescens complex, which comprises four clades; O. nigripes is closely related to Oligoryzomys stramineus, and Oligoryzomys vegetus, to Oligoryzomys fulvescens from Central America. Oligoryzomys chacoensis, O. destructor, O. fornesi, O. longicaudatus, O. microtis, O. nigripes, O. stramineus, Oligoryzomys moojeni, Oligoryzomys rupestris, O. fulvescens and O. vegetus are confirmed as valid species, whereas O. flavescens, Oligoryzomys magellanicus, Oligoryzomys griseolus, Oligoryzomys victus, Oligoryzomys andinus and Oligoryzomys arenalis need exhaustive revision. The sister species to all the remaining entities of the genus was O. microtis, suggesting an Amazonian origin for the genus.     

Distribution and phenology of monarch butterfly larvae and their milkweed hosts in the South Central US

Biodiversity and Conservation - South Central US milkweeds (Asclepias) are critical adult nectar and larval food resources for producing the first spring and last summer/fall generations of...     

Seasonal flooding decreases fruit-feeding butterfly species dominance and increases spatial turnover in floodplain forests of central Amazonia

The seasonal flood pulse in Amazonia can be considered a primary driver of community structure in floodplain environments. Although this natural periodic disturbance is part of the landscape dynamics, the seasonal inundation presents a considerable challenge to organisms that inhabit floodplain forests. The present study investigated the effect of seasonal flooding on fruit-feeding butterfly assemblages in different forest types and strata in central Amazonia. We sampled fruit-feeding butterflies in the canopy and the understory using baited traps in adjacent upland (unflooded forests—terra firme), white and blackwater floodplain forests (várzea and igapó, respectively) during the low- and high-water seasons. Butterfly abundance decreased in the high-water season, especially of dominant species in várzea, but the number of species was similar between seasons in the three forest types. Species composition differed between strata in all forest types. However, the flood pulse only affected butterfly assemblages in várzea forest. The β-diversity components also differed only in várzea. Species replacement (turnover) dominated the spatial β-diversity in igapó and terra firme in both seasons and várzea in the high-water season. Nonetheless, nestedness was relatively higher in várzea forests during the low-water season, mainly due to the effect of dominant species. These results emphasize the importance of seasonal flooding to structure butterfly assemblages in floodplain forests and reveal the idiosyncrasy of butterfly community responses to flooding in different forest types. Our results also suggest that any major and rapid changes to the hydrological regime could severely affect floodplain communities adapted to this natural seasonal hydrological cycle, threatening the existence of these unique environments.