Nesting ecology of a neotropical solitary wasp (Hymenoptera: Sphecidae) in Panamá

Cerceris is a very interesting genus, providing species living in all continents, in different climatic conditions, showing behaviors ranging from solitary to social. About the nesting habit of this genus, many authors described nest characteristics and prey, providing useful material for comparison. Yet, the majority of species studied so far live in temperate regions and we lack information about the tropical ones. The high number of species and their wide distribution suggest a phylogenetic adaptability that merit to be studied deeper. I investigated nest and prey of a tropical species, Cerceris binodis Spinola, on Barro Colorado Nature Monument in Panamá. The study was performed during three dry seasons, marking and excavating nests, observing individual's behavior and collecting prey. The nests, reused over the same season and in following years, are especially deep as observed only in another neotropical species, Cerceris lutzi Scullen . This result could be correlated with tropical soils depth and characteristics. In spite of the species being sexually dimorphic, the subterranean cells show no bimodality in size or content. Prey, identified from specimens carried by provisioning females, belongs to Clytrinae (Coleoptera: Chrysomelidae). Quantitative data on prey are analyzed comparing seasons and sites and differences emerged. Cerceris adaptability to ecological trait of the tropics is inferred to explain these differences as well as the ones observed in the nest structure. Cerceris é um gênero bastante interessante, cujas espécies estão presentes em todos os continentes, em diferentes condições climáticas, mostrando comportamentos variando do solitário ao social. Com relação ao hábito de nidificação desse gênero, muitos autores descreveram as características do ninho e das presas, provendo material útil para comparações. Além disso, a maioria das espécies estudadas até agora vivem em regiões temperadas e faltam informações sobre as tropicais. O grande número de espécies e sua ampla distribuição sugerem uma adaptabilidade filogenética que merece ser estudada mais profundamente. Neste trabalho foram investigados o ninho e a presa da espécie tropical Cerceris binodis Spinola, no Barro Colorado Natural Monument no Panamá. O estudo foi realizado durante três estações secas, marcando e escavando os ninhos, observando o comportamento dos indivíduos e coletando a presa. Os ninhos, reutilizados na mesma estação e nos anos seguintes, são especialmente profundos, como observados somente em outra espécie neotropical, Cerceris lutzi Scullen. Esse resultado pode ser correlacionado com a profundidade de solos tropicais e suas características. Apesar de as espécies apresentarem dimorfismo sexual, as celas subterrâneas não mostram diferenças no tamanho ou no seu conteúdo. A presa, identificada dos espécimes carregados pelas fêmeas provedoras, pertencem a Clytrinae (Coleoptera: Chrysomelidae). Os dados quantitativos sobre a presa foram analisados por comparação das estações e locais, evidenciando as diferenças. Infere-se que a adaptabilidade de Cerceris às características ecológicas dos trópicos pode explicar essas diferenças assim como as observadas na estrutura do ninho

Washboarding: Are Man-Managed Honeybees Performing a Vestigial Activity Fostered by Cryptogams?

A common view is that honeybees are mostly managed by beekeepers for commercial purposes or as a hobby, especially in Europe. This misconception is probably due to the lack of systematic studies on wild colonies of honeybees in Europe in comparison to other regions of the world. Since we are used to considering this species as “domesticated”, we may be induced to disregard activities not distinctly linked with colony survival, reproduction, or productivity. Washboarding is one of them in which the entire colony stops resource collection activities; numerous individual bees assemble on the front side of the hive and perform repetitive movements back and forth. They are curiously synchronised but apparently without a scope. In this exploratory work, we carried out a literature review of available, mostly grey, literature. Assuming this behaviour may be linked to cavity-nesting and to tree trunks or rocks being rough surfaces hosting various cryptogams, we performed preliminary observations and manipulative experiments. From our survey, we depict that washboarding is frequently reported in grey literature/beekeepers’ reports, but rarely mentioned in scientific literature. Beekeepers who responded to a designed questionnaire observed this behaviour in various ecological situations, with no trend emerging. Our preliminary experiment of placing cryptogams in front of managed hives resulted in honeybees removing lichens (foliose types) or covering with propolis, and all species were affected. Further research is needed to clarify if lichens are removed because of their chemical compounds, because of hosting potentially toxic microorganisms, or collected as resourcesinfo:eu-repo/semantics/publishedVersio

Australian acacias across eastern Adriatic – abundant but not aggressive

Background and Purpose: Biological invasions are considered among the main factors of global changes and the identification of future invaders may help in taking effective steps to prevent their dispersal and/or establishment. For some Australian Acacia species, especially Acacia dealbata Link, an invasive status has been already described in some European countries. The aim of this work was surveying the actual spatial pattern of Australian acacias across the eastern Adriatic, and, by applying GIS techniques, to learn more about their ecology and distribution. Materials and Methods: We carried on two field surveys during the flowering season of the year 2014, and recorded the locations of Acacia species, their flowering state, floral characteristics, and the insects present on the inflorescences. We georeferenced any plant detected, and collected soils samples under the plant crowns and in close natural or semi-natural areas. Results and Conclusions: Very few species were recorded and mostly in private gardens, A. dealbata being the preferred ornamental. Records referring to plants grown in abandoned or unattended gardens demonstrate the potential of this species to expand if not properly controlled. In addition, we detected no plants outside gardens in natural habitats. Results on soil characteristics, with higher pH values than those usually found under trees of this genus elsewhere, may partly explain our findings. The surveys took place during a spring following an unusually warm winter: this may have influenced both phenology and pollinator activity, finally reducing observations of the latter. Descriptive statistics and MaxEnt analysis have shown the importance of the warmer areas in determining the presence of Acacia species. At present, acacias are not to be considered aggressive invaders along the eastern Adriatic according to our observations; they can be classified as alien, with a local trend toward becoming casual

Morphofunctional Traits and Pollination Mechanisms of Coronilla emerus L. Flowers (Fabaceae)

It is accepted that the papilionaceous corolla of the Fabaceae evolved under the selective pressure of bee pollinators. Morphology and function of different parts of Coronilla emerus L. flowers were related to their role in the pollination mechanism. The corolla has a vexillum with red nectar lines, a keel hiding stamens and pistil, and two wing petals fasten to the keel with two notched folds. Pollinators land on the complex of keel and wings, trigger the protrusion of pollen and finally of the stigma from the keel tip. Data on pollen viability and stigma receptivity prove that flowers are proterandrous. The results of hand-pollination experiments confirmed that insects are fundamental to set seed. Interaction with pollinators allows not only the transport of pollen but also the rupture of the stigmatic cuticle, necessary to achieve both allogamy and autogamy. Field observations showed that Hymenoptera, Lepidoptera, and Diptera visited the flowers. Only some of the Hymenoptera landed on the flowers from the front and elicited pollination mechanisms. Most of the insects sucked the nectar from the back without any pollen transfer. Finally, morphological and functional characteristics of C. emerus flowers are discussed in terms of floral larceny and reduction in pollination efficiency

Winter collection of the underutilized berry Corema album (L.): New insights on its maturation progression

Increasing interest in Corema album L. is raising due to the appealing white colour and potential health benefits related to its bioactive composition. White fruits production culminates in late August on coastal dunes, but fruits of various colours are present almost till flowering (late February). We undertook a preliminary physical-chemical characterisation (biometric, CIELab colour, pH, soluble solids content and titrable acidity) of a late fruit collection to disentangle maturity progression and to reveal latent qualities for future utilisation. Irrespective of fruit perceived colouration (white, translucent, brown, brown with black spots and black), the characterized high acidity (1-3 g.100 mL-1) is suggestive that over-mature fruits can still be further explored as food additives. Moreover, using a multivariate exploratory technique, we found a clear fruit’s maturation progression from white/translucent to black, a so-far unreported maturity stage. Addressing gaps in plant phenology and fruit’s maturity behaviour is needed before undertaking cultivation.info:eu-repo/semantics/publishedVersio

From canopy to single flowers: a downscale approach to flowering of the invasive species Acacia longifolia

Context: Acacia longifolia is a native legume of south-eastern Australia and Tasmania and is invasive in many parts of the world. A key feature to its success is the production of a high quantity of flowers every season, resulting in a massive seedbank that remains dormant in the soil for decades. Many studies have been performed on this species’ reproductive biology, but none has focused on flowering in detail. Aims: Our main objective was to understand this species’ resource allocation strategy that ensures its successful reproduction in the invasive range. Methods: We developed an integrative approach, assessing flowering at different levels, namely, canopy and branch flowering (macro scale), downscaling to individual flower functional stages and their duration, pollen longevity and stigma receptivity (micro scale). We performed this study in three different locations in sand dunes along the Portuguese coast with different environmental conditions. Key results: Canopy flowering shows no difference among sites. Pollen and stigma assessment showed that this species is protogynous, with the stigma being highly receptive long before pollen is released. Once released, pollen lasts roughly 72 h. Individual flowers are relatively short-lived, with a rapid progression from closed flower buds to fully open flowers. Implications: Our results indicated that A. longifolia has a resource trade-off strategy of investing in flowers and pollen that are relatively short-lived, which are counterbalanced by their massive quantities.info:eu-repo/semantics/acceptedVersio

From flower to honey bouquet: possible markers for the botanical origin of Robinia honey.

Flowers are complex structures devoted to pollinator attraction, through visual as well as chemical signals. As bees collect nectar on flowers to produce honey, some aspects of floral chemistry are transferred to honey, making chemical markers an important technique to identify the botanical and geographical origins of honey. We applied a new approach that considers the simultaneous analysis of different floral parts (petals, stamens + pistils, calyxes + nectarines, and nectar) and the corresponding unifloral honey. We collected fresh flowers of Robinia pseudoacacia L. (black locust), selected five samples of Robinia honey from different geographical origins, applied SPME-GC/MS for volatile analyses, and defined the chemical contribution added by different floral parts to the honey final bouquet. Our results show that honey blends products from nectar as well as other flower parts. Comparing honey and flower profiles, we detected compounds coming directly from flower parts but not present in the nectar, such as hotrienol and β-pinene. These may turn out to be of special interest when selecting floral markers for the botanical origin of honey

Acorn isotopic composition: A new promising tool for authenticity maps of Montado’s high-value food products

It is often overlooked that even food production is linked to the ecology of plants and animals. Living organisms respond to environmental short-and long-term variability: acknowledging this may help in the ultimate goal of valorizing a territory/product. We investigated acorns of the two main Quercus species of the Portuguese Montado, a main feed of the renown black Iberian pig. We tested their responses to an aridity gradient by morphological parameters and isotopic signature. Q. rotundifolia and Q. suber acorns did not differ morphologically, even if a higher variability in all parameters was observed in acorns of Q. suber. According to the site-specific Aridity Index, correlations are indicative to higher weight and length only in Q. suber acorns from more arid sites. As for isotopic composition, there were no differences in nitrogen or carbon (δ15N and δ13C) between the two species. However, combining the samples and testing for association with the Aridity Index, we found that more arid sites lead to a 15N enrichment. This result, combined with the positive correlation between AI and acorns length, support the use of acorns as a tool, their isoscapes of nitrogen being a stepping stone for the provenance of the black Iberian pig.info:eu-repo/semantics/publishedVersio

A botanic garden as a tool to combine public perception of nature and life-science investigations on native/exotic plants interactions with local pollinators

Life-sciences are pointing towards an alarming worldwide pollinator decline. This decline proceeds along with overall biodiversity losses, even in the context of urban landscapes and human welfare. At the same time, social-sciences are arguing an increased distance from nature, experienced by citizens. The strong connection between the public good and pollinator sustainability, even in urban areas, is well-documented. However, usually basic and applied life-sciences tend to underestimate public perception of nature, which is better tackled by the fields of social-sciences. Therefore, more efforts are needed to link scientific questions and public 'perception' of nature. We designed a transversal project where research questions directly confront public concerns: i.e., even while addressing scientific knowledge gaps, our questions directly arise from public concerns. Social studies highlighted that appreciation of (exotic) plants is related to the impact they may have on the surrounding natural environment: therefore, we investigated links of native and exotic flowers to local pollinators. Other studies highlighted that scientific results need to link to everyday individual experience: therefore, we investigated pollination modes of the renown Salvia, native and exotic, largely used in cuisine and gardening. The botanic garden was the promoter of scientific questions addressed by the public, and also collated the results in a travelling exhibition. The exhibition, together with a dedicated catalogue, were especially designed to enlighten the wide public on the relationships that plants, native and exotic alike, establish with the surrounding world.info:eu-repo/semantics/publishedVersio

Quality attributes of cultivated white crowberries (Corema album (L.) D. Don) from a multi-origin clonal field

There is a growing interest in Corema album (L.) D. Don fruits due to the unique white colour, mildly acidic lemony flavour and health-promoting properties associated with its bioactive composition. This study performs a physical–chemical characterisation of cultivated C. album fruits from a multi-origin clonal field. The field comprises ten wild populations with distinct geographical origins, grown under the same edaphoclimatic conditions. We analysed fruits CIELab colour parameters, texture profile (TPA), pH, acidity (TA, g.100 mL−1), soluble solids content (SSC, %) and total phenolic content (TPC, mg CAE.100 g−1). Our results showed differences between fruits physical–chemical attributes. Variation patterns in fruits SSC and hardness suggest that the differences might be related to the original geographical location of the populations. The determined TPC levels in all samples were very encouraging at a bioactive level, ranging from 185.3 to 355.6 mg CAE.100 g−1. Fruits from Mira and Pego populations stood out from the ten geographical provenances. Mira fruit samples had higher sweetness and lower acidity, while the Pego ones had firmer fruits and higher phenolic content. The multi-origin clonal field allowed us to offer an interesting scientific comparative background, highlighting the large potential of these berries for introduction in the commercial market. Not only our results support the potential of white crowberry as a new crop; the detected differences also indicate a hidden capacity for small fruit market diversification.info:eu-repo/semantics/publishedVersio