Zhailimeryx, A New Lophiomerycid Artiodactyl (Mammalia) from the Late Middle Eocene of Central China and the Early Evolution of Ruminants

A new genus and species of primitive selenodont artiodactyl, Zhailimeryx jingweni, occurs in the late middle Eocene Zhaili Member of the Heti Formation, Yuanqu Basin, Shanxi Province, China. A phylogenetic analysis of dental characters suggests that Zhailimeryx is closely related to Lophiomeryx and other lophiomerycid ruminants of Asia and Europe. Zhailimeryx and other Eocene records of Lophiomerycidae from Asia support an Asian origin for this family, followed by dispersal into Europe both before and after the Grande Coupure. Morphological evidence from Zhailimeryx suggests that ruminant artiodactyls had already undergone substantial diversification prior to the late middle Eocene, and it reopens the issue of whether the higher taxa Tragulina and Pecora are valid expressions of ruminant phylogeny.     

Effects of different abiotic and biotic factors on spatial primary seed dispersal in the semachorous species Scrophularia canina

Seed dispersal is one of the most important steps in the plant life cycle. However, there is, generally, a lack of fieldworks focused on wind dispersal and especially on semachorous dispersal (seeds spread when the fruits are shaken by wind and other vectors, such as animals), including boleochorous dispersal. Therefore, we aimed to determine how different types of wind and animals affected seed dispersal under natural conditions in the widespread species Scrophularia canina. We evaluated the effects of wind gusts (simulating them using a leaf blower) and wild animals (using differently sized dogs) on seed dispersal in a population located in south-western Europe. We found that S. canina is a semachorous species, and its spatial seed dispersal was affected by wind gust speed and direction, plant structure and vector type. The results also revealed the presence of xerochasy, individual anisotropy with strong winds, and primary short-distance dispersal associated with successional processes independent of the vector. Additionally, there was a masking effect of plant structure on the seed shadow outline. It is essential to conduct fieldworks to reveal what actually happens in nature, taking into account the characteristics determining seed dispersal. In addition, in these works it is important to find out what factors affect seed distributions of anemochorous and semachorous species.     

A dig into the past mitochondrial diversity of Corsican goats reveals the influence of secular herding practices

The goat (Capra hircus) is one of the earliest domesticated species ca. 10,500 years ago in the Middle-East where its wild ancestor, the bezoar (Capra aegagrus), still occurs. During the Neolithic dispersal, the domestic goat was then introduced in Europe, including the main Mediterranean islands. Islands are interesting models as they maintain traces of ancient colonization, historical exchanges or of peculiar systems of husbandry. Here, we compare the mitochondrial genetic diversity of both medieval and extant goats in the Island of Corsica that presents an original and ancient model of breeding with free-ranging animals. We amplified a fragment of the Control Region for 21 medieval and 28 current goats. Most of them belonged to the A haplogroup, the most worldwide spread and frequent today, but the C haplogroup is also detected at low frequency in the current population. Present Corsican goats appeared more similar to medieval goats than to other European goat populations. Moreover, 16 out of the 26 haplotypes observed were endemic to Corsica and the inferred demographic history suggests that the population has remained constant since the Middle Ages. Implications of these results on management and conservation of endangered Corsican goats currently decimated by a disease are addressed.     

A GIS-based Model of the Distribution of the Rare Liverwort Aneura maxima at the Landscape Scale for an Improved Assessment of Its Conservation Status

Testing whether rare species are limited by narrow habitat conditions from correlations between species occurrence and measured environmental factors is usually hampered by the lack of statistical power associated to the low number of observations. Aneura maxima is an exceedingly rare liverwort in Europe whose recent discovery precluded the inclusion within the Red Data Book of European bryophytes. A series of new observations resulting from intensive bryophyte grid-mapping at the border between France and Belgium allowed the statistical investigation of the factors accounting for its distribution at the landscape scale. The species was systematically observed in deep ravines on damp, loamy soils under light tree cover within broadleaf woodlands. These conditions differ from those of other European localities, suggesting that A. maxima is not limited by a narrow ecological range. Attempting to predict the occurrence of A. maxima at the landscape scale from data on land use and soil conditions resulted in a model where the species was actually observed in only a half of the squares where its probability of occurrence was the highest. The species thus does not seem to have colonized all its potential habitats, which may be explained by the poor dispersal ability of this dioecious, rarely fertile species. Given the relative frequency of A. maxima in the Semois river basin, but taking into account its seemingly low dispersal ability and its preference for swampy habitats that are threatened by draining and spruce plantations, a status as 'conservation dependent' to 'near threatened' within the category 'lower risk' is proposed.     

Spatial and temporal variation in dispersal pattern of an invasive pine

Understanding dispersal ability of an invasive species is crucial for describing its potential spread. Despite this, we still know little about the dispersal potential of many invasive species. We explored dispersal spectra in Pinus strobus, an invasive tree in sandstone areas in Central Europe. We studied dispersal of the species using distribution of self-sown trees in the field. We compared these observed data with theoretical dispersal curves derived using information on wind speed, seed terminal velocity and tree height. Finally, we fitted various empirical dispersal curves to the observed data. All the analyses based on the observed field data were done for the whole dataset, and for the dataset divided by habitat types and age categories of the self-sown trees. P. strobus seeds can disperse up to 757.5 m from the source. The observed data fall within the confidence intervals of the predictions based on a negative exponential model. When comparing different dispersal functions fitted to the data, it was not easy to decide which of the dispersal curves provides the overall best fit. This was because different functions were the best predictors of different parts of the dispersal curve. We suggest that future studies should provide not only empirical fitted dispersal curves but also observed data and provide estimates of confidence intervals. Such information will provide insights into the reliability of the dispersal estimates in general and help to evaluate the predictive power of the different models.     

Estimation of the dispersal of a major pest of maize by cline analysis of a temporary contact zone between two invasive outbreaks

Dispersal is a key factor in invasion and in the persistence and evolution of species. Despite the importance of estimates of dispersal distance, dispersal measurement remains a real methodological challenge. In this study, we characterized dispersal by exploiting a specific case of biological invasion, in which multiple introductions in disconnected areas lead to secondary contact between two differentiated expanding outbreaks. By applying cline theory to this ecological setting, we estimated σ, the standard deviation of the parent–offspring distance distribution, of the western corn rootworm, Diabrotica virgifera virgifera, one of the most destructive pests of maize. This species is currently invading Europe, and the two largest invasive outbreaks, in northern Italy and Central Europe, have recently formed a secondary contact zone in northern Italy. We identified vanishing clines at 12 microsatellite loci throughout the contact zone. By analysing both the rate of change of cline slope and the spatial variation of linkage disequilibrium at these markers, we obtained two σ estimates of about 20 km/generation^1/2. Simulations indicated that these estimates were robust to changes in dispersal kernels and differences in population density between the two outbreaks, despite a systematic weak bias. These estimates are consistent with the results of direct methods for measuring dispersal applied to the same species. We conclude that secondary contact resulting from multiple introductions is very useful for the inference of dispersal parameters and should be more widely used in other species.     

The rise and fall of an alien: why the successful colonizer Littorina saxatilis failed to invade the Mediterranean Sea

Understanding what determines range expansion or extinction is crucial to predict the success of biological invaders. We tackled this long-standing question from an unparalleled perspective using the failed expansions in Littorina saxatilis and investigated its present and past habitat suitability in Europe through Ecological Niche Modelling. This intertidal snail is a typically successful Atlantic colonizer and the earliest confirmed alien species in the Mediterranean Sea, where, however, it failed to thrive despite its high dispersal ability and adaptability. We explored the environmental constraints affecting its biogeography, identified potential glacial refugia in Europe that fuelled its post-glacial colonisations and tested whether the current gaps in its distribution are linked to local ecological features. Our results suggested that L. saxatilis is unlikely to be a glacial relict in the Mediterranean basin. Multiple Atlantic glacial refugia occurred in the Last Glacial Maximum, and abiotic environmental features such as salinity and water temperature have influenced the past and current distributions of this snail and limited its invasion of the Mediterranean Sea. The snail showed a significant overlap in geographic space and ecological niche with Carcinus maenas, the Atlantic predator, but distinct from Pachygrapsus marmoratus, the Mediterranean predator, further pointing to Atlantic-like habitat requirements for this species. Abiotic constrains during introduction rather than dispersal abilities have shaped the past and current range of L. saxatilis and help explaining why some invasions have not been successful. Our findings contribute to clarifying the processes constraining or facilitating shifts in species’ distributions and biological invasions.

     

On the spread of the Russian sturgeon Acipenser gueldenstaedtii (Acipenseriformes: Acipenseridae) in the Neotropics: A marine path to invade freshwater drainages in South America?

Acipenser gueldenstaedtii is a species of sturgeon described from Caspian Sea and Black Sea and their tributaries, occurring in the Eastern Atlantic, Europe and Middle East. This and other two sturgeon species have been accidentally introduced in the Rio Negro, Uruguay, a tributary of the Rio de La Plata. Recently, it has been demonstrated the presence and establishment of A. gueldenstaedtii widespread in the Rio Paraná basin, the largest tributary of the Rio de La Plata, corresponding to the second largest river drainage in the Neotropics. We herein register the presence of the species in the next northern freshwater drainage in South America, representing the first record for Brazil. We further discuss the possibility of dispersal through marine environments to other freshwater drainages in South America through the analysis of its documented occurrence and marine ecoregions in southwestern Atlantic.     

Dispersal traits and dispersal patterns in an oro-Mediterranean thorn cushion plant formation of the eastern High Atlas, Morocco

This study describes the dispersal traits and dispersal patterns of 51 perennial plant species belonging to 19 families in an oro-Mediterranean thorn cushion plant formation on the High Atlas, Morocco. Diaspore type, mass, number, antitelechoric mechanisms and dispersal time were studied with respect to growth forms, dispersal modes and spatial dispersal. Species spanned 10⁵ range of diaspore mass, which coincided with those found in other high mountain regions. Diaspore mass was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. Barochorous and zoochorous species are more likely to have heavy diaspores, whereas anemochorous and ballistic species have a medium diaspore mass and semachorous and ombro-hydrochorous species have low diaspore mass. Diaspore number was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. The barochorous, ombro-hydrochorous and zoochorous species tended to produce higher diaspore numbers than species with other dispersal modes. Bradyspory was well-developed by trees and large shrubs dispersed by biotic vectors. Synaptospermy was represented by its long dispersal component. Myxospermy was significantly associated with semi-shrubs and perennial herbs with restricted spatial dispersal. It seems that ombro-hydrochory combined with myxospermy and a high number of light seeds is an efficient mechanism that ensures successful establishment of the most typical and endemic thorn cushion plant species, such as Alyssum, Vella and Ormenis. In our study area, the highest dispersal availability was synchronized with the dry summer season (July–August) and the beginning of the rainy months (September). The dispersal peak for the wind-dispersed species, which is the most effective primary dispersal mode, occurs during the dry season, while dispersal for the biotic-dispersed species takes place throughout the year.     

Monitoring and dispersal of the invading Gracillariidae Cameraria ohridella

The horse‐chestnut leafminer Cameraria ohridella is an invasive lepidoptera (Gracillariidae) which has spread throughout Europe over the last two decades. The species can be detected easily because of its noticeable damage to horse‐chestnut trees leaves, which allows the easy collection of large‐scale monitoring data. It is therefore an interesting model species to study invasion processes, and this review summarizes recent progresses in that regard. The date reported here result from monitoring of C. ohridella population based on pheromone traps and visual observation of damage carried out in Belgium, France, Germany, Switzerland and the UK. The patterns of spread measured using these different monitoring method, and the key factors associated with short‐distance dispersal (within cities), and large‐scale dispersal (across landscapes) are presented and discussed.     

Strongly diverging population genetic patterns of three skipper species: the role of habitat fragmentation and dispersal ability

The fragmentation of landscapes has an important impact on the conservation of biodiversity, and the genetic diversity is an important factor for a populations viability, influenced by the landscape structure. However, different species with differing ecological demands react rather different on the same landscape pattern. To address this feature, we studied three skipper species with differing habitat requirements (Lulworth Skipper Thymelicus acteon: a habitat specialist with low dispersal ability, Small Skipper Thymelicus sylvestris: a habitat generalist with low dispersal ability, Essex Skipper Thymelicus lineola: a habitat generalist with higher dispersal ability). We analysed 18 allozyme loci for 1,063 individuals in our western German study region with adjoining areas in Luxembourg and north-eastern France. The genetic diversity of all three species were intermediate in comparison with other butterfly species. The F _ST was relatively high for T. acteon (5.1%), low for T. sylvestris (1.6%) and not significant for T. lineola. Isolation by distance analyses revealed a significant correlation for T. sylvestris explaining 20.3% of its differentiation, but no such structure was found for the two other species. Most likely, the high dispersal ability of T. lineola in comparison with T. sylvestris leads to a more or less panmictic structure and hence impedes isolation by distance. On the other hand, the isolation of the populations of T. acteon seems to be so strict that the populations develop independently. Although no general genetic impoverishing was observed for the endangered T. acteon, small populations had significantly lower genetic diversities than big populations, and therefore the high degree of isolation among populations might threaten its local and regional survival.     

Updating Geographic Distribution of Artemia urmiana Günther, 1890 (Branchiopoda: Anostraca) in Europe: An Integrated and Interdisciplinary Approach

Artemia urmiana (a species previously considered endemic of Lake Urmia, NW Iran) has been found in Lake Koyashskoe, a hypersaline lake on the Black Sea coast of the Crimean peninsula (Ukraine). Therefore, this is the first record of A. urmiana in Europe which updates its distribution. The species identification was based on an integrated and interdisciplinary approach using discriminant analysis of the morphometric characters, scanning electron microscopy, and molecular profile analysis. The data derived from the above mentioned approaches converge to significant similarity of the population under investigation with A. urmiana. The updated geographic distribution of the species, deriving from the present report, asks for additional contribution of other disciplines (e.g., avian dispersal of cysts, history of salt trade) to be finally clarified. At present we suggest that the punctuated geographic distribution of A. urmiana is probably linked to its low dispersal capability, and we suppose that its presence in two distant sites could be explained by historical human salt trade between Lake Urmia and the ancient port of Kimmerik, whose remains have been found in the present Lake Koyashskoe. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The historical ecology of yellow perch (Perca flavescens[Mitchill]) and their parasites

Aim To determine the origins of the host–parasite association between among yellow perch (Perca flavescens[Mitchill]) and the parasites Crepidostomum cooperi Hopkins, Proteocephalus pearsei La Rue and Urocleidus adspectus Beverly Burton. Of secondary interest are the parasites Bunodera luciopercae (Muller) and Proteocephalus percae (Muller) predictably associated with the Eurasian perch. Location The areas considered are the Holarctic, since the upper‐Cretaceous, and contemporary North America. Methods Published and new information from host and parasite phylogenies, palaeontology, palaeogeography and plate tectonics and host biology is incorporated to assess the origins of yellow perch and several of its parasites. This information is used to determine the origins for these host–parasite associations. Results Cladistic analysis suggests a Laurasian origin for Percidae and Perca, and that Perca is sister to the other genera in the family. Parasite phylogenies support a North American origin for the three species associated with yellow perch and a Laurasian origin for B. luciopercae. Proteocephalus pearsei and P. percae are not sister taxa. The fossil record for Perca dates to the Miocene in Europe and the Pleistocene in North America. North America and Europe were connected across the North Atlantic since at least the upper Cretaceous with separation complete by the Miocene. Europe was separated from Asia by the Obik Sea from the late Cretaceous until the Oligocene. Western cordillera orogeny and its accompanying high rates of water flow and Pleistocene glaciation represent barriers to Perca dispersal. Main conclusions The origin of Perca in North America dates at least to the late Oligocene when North America and Europe were connected across the North Atlantic and Europe and Asia were separate landmasses, and does not result from Pleistocene dispersal across Beringia from Asia. The present disjunction of Perca species in North America and Europe is due to the vicariant separation of North America and Europe. Based on the available information, yellow perch and its parasites have a North America origin. The association between yellow perch and the parasites in all cases is a consequence of host switching from other sympatric host species in North America and is not explained by co‐speciation. Even the association between the host‐specific Urocleidus adspectus and yellow perch originated with a host switch and is not due to co‐speciation. The basis for this host switching is geographical and ecological sympatry, especially shared feeding habits, with other North American fish hosts.     

Molecular phylogeny of the Sphaerophorus globosus species complex

The Sphaerophorus globosus complex (Lecanorales, lichenized Ascomycota) shows a large morphological variation, and three relatively distinct morphotypes can be distinguished in parts of the distribution area. Here, we utilize a multigene‐based maximum‐parsimony approach (nITS+ LSU rDNA, mtSSU rDNA, β‐tubulin, and actin) to investigate whether these morphotypes constitute distinct species. The results show that there are at least two well‐supported monophyletic groups that we interpret as phylogenetic species within the S. globosus complex. These species do not completely correspond to the predefined morphotypes. One group, an apparently undescribed species, contains noncoralloid specimens from the North American Pacific Northwest. The other group, S. globosus, consists of two well‐supported monophyletic groups: one contains coralloid epiphytic specimens from the North American Pacific Northwest that are morphologically indistinguishable from epiphytic specimens from Europe and are presently interpreted as belonging to the same species and the other is morphologically variable and contains terrestrial specimens from Europe, North America, and southernmost South America and coralloid epiphytic and epilithic specimens from Europe. The results suggest that the population in southernmost South America originated by long‐distance dispersal from arctic populations in the Northern Hemisphere.     

Harmonia axyridis: an environmental risk assessment for Northwest Europe

In this paper, we summarize the international situation with respect to environmental risk assessment for biological control agents. Next, we apply a recently designed, comprehensive risk evaluation method consisting of a stepwise procedure to evaluate the environmental risks of Harmonia axyridis in Northwest Europe. This resulted in the very clear conclusion that H. axyridis is a potentially risky species for Northwest Europe, because it is able to establish, it has a very wide host range including species from other insect orders and even beyond the class of Insecta, it may feed on plant materials, it can cover large distances (>50 km per year), it does move into non-target areas, it may attack many non-target species including beneficial insects and insects of conservation concern, its activities have resulted in the reduction of populations of native predators in North America, it is known as a nuisance in North America and recently also in Northwest Europe, and it may develop as a pest of fruit in North America. Considering the H. axyridis case, current knowledge would lead to the conclusion that, although the predator is capable to effectively control several pest species, its risks are manifold and it should, thus, not have been released in Northwest Europe. At the time of the first releases in Nortwest Europe in 1995, the available scientific literature made clear that H. axyridis is a large sized polyphagous predator and has a great reproductive capacity in comparison with other ladybird beetles, and that there was a need to study non-target effects because of its polyphagous behaviour. In retrospect, this information should have been sufficient to reject import and release of this species, but it was apparently ignored by those who considered release of this predator in Northwest Europe. The case of Harmonia releases in Northwest Europe underlines that there is an urgent need for harmonized, world-wide regulation of biological control agents, including an information system on risky natural enemy species.     

Spatial ecology of multiple parasitoids of a patchily‐distributed host: implications for species coexistence

1. The coexistence of multiple species sharing similar but spatially fragmented resources (e.g. parasitoids sharing a host species) may depend on their relative competitive and dispersal abilities, or on fine‐scale resource partitioning. Four generalist and one specialist parasitoid species associated with the holly leaf miner, Phytomyza ilicis, in a woodland network of 127 holly trees were investigated. 2. To understand coexistence and persistence of these potential competitors, patterns of occurrence in relation to patch size and isolation, vertical stratum within patches, and incidence and abundance of potential competitors were documented. Field experiments creating empty habitat patches suggested that dispersal rather than local demographic processes determines abundance and incidence. 3. Parasitoids showed species‐specific responses to patch properties, with the incidence of species determined mostly by patch size. Parasitism rates were less clearly related to patch characteristics, but parasitism rates for most species were lower in patches where the numerically dominant parasitoid species, Chrysocharis gemma, was present. No evidence of vertical stratification was found in species composition or abundance within patches, making it unlikely that coexistence is enhanced by fine‐scale resource division. 4. Overall, the patterns detected may be attributed to the distribution of C. gemma and differences in species' ecology other than dispersal ability. The life history of C. gemma may allow it to pre‐emptively exploit a large fraction of the available hosts, avoiding direct competition with other parasitoids. In contrast, direct competition is more likely among the pupal parasitoids Cyrtogaster vulgaris, Chrysocharis pubicornis, and Sphegigaster flavicornis which have a similar biology and phenology. For these species, coexistence may be facilitated by contrasting incidence in relation to patch size and isolation.     

Biogeography of Aegagropila linnaei (Cladophorophyceae,Chlorophyta): a widespread freshwater alga with low effective dispersal potential shows a glacial imprint in its distribution

Aim Aegagropila linnaei is a freshwater macroalga that is generally regarded as a rare species. It is apparently absent from large but seemingly suitable areas of the Northern Hemisphere, implying a limited dispersal potential and an imprint of Pleistocene glaciations in its biogeography. However, despite the popularity of its enigmatic lake ball‐form, detailed biogeographical studies of A. linnaei have never been conducted. The main means of reproduction of A. linnaei is fragmentation and akinetes are not formed, supporting the assumption of limited dispersal capacity. The aim of this study was to reconstruct the biogeography of A. linnaei, and to identify possible refugia during glaciations, as well as to evaluate dispersal potential by quantitative desiccation experiments. Location Palaearctic. Methods The current distribution of A. linnaei was inferred from herbarium specimens, literature data and recent field observations. All herbarium specimens were morphologically re‐examined. Desiccation experiments were performed with vegetative filaments of three isolates of A. linnaei, as no specialized resistant stages are known. For comparison, the widespread freshwater algae Cladophora glomerata and Rhizoclonium sp. were included. Internal transcribed spacer (ITS) ribosomal DNA sequences were generated and a ribotype network was constructed. Results Aegagropila linnaei was recorded from 283 locations in freshwater and brackish environments. The majority of locations were in central and northern Europe in previously glaciated areas. Desiccation experiments showed that A. linnaei is very susceptible to desiccation. Based on ITS sequences of 34 samples, five different ribotypes were identified. Four of these ribotypes had a restricted distribution. Aegagropila linnaei represents a single species with little genetic variation (0.1–0.5%). Main conclusions This is the most comprehensive study of this species so far, reporting many new locations and tackling several taxonomic problems. Few additional finds were made from North America, and the origin of A. linnaei is inferred to be in Asia. The highest density of its present‐day locations is in previously glaciated areas in Europe, where glacial ice‐dammed lakes might have functioned as refugia. Low effective long‐distance dispersal capacity is inferred, based on high susceptibility to desiccation and its modes of dispersal.     

The barriers to oceanic island radiation in bryophytes: insights from the phylogeography of the moss Grimmia montana

Aim In contrast to angiosperms, bryophytes do not appear to have radiated in Macaronesia and the western Mediterranean. We evaluate if: (1) the apparent lack of radiation in bryophytes reflects our failure to recognize cryptic endemic species; (2) bryophytes are characterized by extremely low evolutionary rates; or (3) bryophytes have a high dispersal ability, which prevents genetic isolation. Location Worldwide, with a special emphasis on Macaronesia and the western Mediterranean. Methods Three chloroplast regions were sequenced from samples of the moss Grimmia montana from its entire distribution range. Network analyses, Fst and Nst statistics were used to describe and interpret the phylogeographical signal in the data. Results Despite significant phylogeographical signal in the chloroplast genome, which demonstrates limits to gene flow at the continental scale, repeated sister group relationships observed among accessions from different geographical areas suggest recurrent colonization patterns. These observations are consistent with mounting evidence that intercontinental distributions exhibited by many bryophyte species result from long‐distance dispersal rather than continental drift. Madeiran and western Mediterranean island haplotypes are either shared by, or closely related to, European and North American ones. Fst values between Madeira, western Mediterranean islands, North America and Europe are not significantly different from zero, and suggest that Madeira and the south‐western Mediterranean are subject to strong transatlantic gene flow. By contrast, haplotypes found in the Canary Islands are shared or closely related to those of populations from south‐western Europe or southern Africa. Main conclusions Multiple origins and colonization events are not consistent with the hypothesis of a relictual origin of the Macaronesian moss flora. One possible reason for the failure of taxa that experienced multiple colonization events to radiate is niche pre‐emption. We suggest that strong gene flow, coupled with the occupancy of all suitable niches, either by earlier conspecific colonizers or by other species, could be the mechanism preventing island radiation in G. montana and other cryptogams with high long‐distance dispersal abilities.     

What happens when fire is too early? Observations of fire-stimulated fruit opening releasing underdeveloped seeds for an endemic Cerrado shrub

The relation of fire with the reproductive process of species from tropical grasslands and savannas has long been investigated. Post-fire flowering is well documented in the Cerrado, but fire-mediated fruit opening and seed dispersal has rarely been described, with very few historical records being known. Even less is known about the effects of different fire seasons on species reproduction. Here, we describe the fire-stimulated fruit opening of Jacaranda ulei, an endemic Cerrado shrub with medical importance to traditional communities. We show that fruits opened within 2 weeks after an early dry season fire, but there were almost no viable seeds as fruits were still immature when burned. When put together with the known records for other species, dry dehiscent fruits and anemochory arise as common traits that favour fire-mediated fruit opening. As these are common attributes in the Cerrado, it is possible that several other species also have fire-stimulated seed dispersal but remain vastly unnoticed and underreported in the literature. Additionally, the peak reproductive effort of these species coincides with the period of prescribed burns of the Integrated Fire Management Program and, consequently, several species could also have their reproductive cycle interrupted to disperse immature seeds. We hope our note encourages further studies on the fire-mediated fruit opening and seed dispersal of Cerrado species, particularly in relation to fire season and seed quality.     

Internal transport of alien and native plants by geese and ducks: an experimental study

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