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Impact of pollination on the agri-food sector is of paramount importance. Pollinators contribute to the maintenance of ecosystems, the reproduction and survival of many plants, and their presence usually leads to increased yield and quality of agricultural products. Breeding and selecting for plant traits for enhancing pollinator visits could therefore lead to more resilient farming systems. In stating the advantages of enhancing pollinators in agricultural systems, this study was designed aiming to assess six cowpea accessions for their flower traits and their effect on insect-pollinators. Pollinators species abundance and foraging activity was recorded and their impact on yield was investigated. Twenty-five of the twenty-seven flower traits studied differed statistically significantly among cowpea accessions. The main pollinators recorded belonged to the genus Xylocopa (Latreille, 1802). Seed and fresh pod yield was not affected by pollinators. The floral traits related to pollinators abundance and foraging activity were flower color, inflorescence position and the hours that the flowers per plant remained open during the day. However, they were not related linearly to pollinators abundance and foraging activity; therefore, they did not constitute safe traits for selection aiming to increase pollinators visitation. The findings suggested that other traits, such as pollen and nectar reward, probably perform a more important role in attracting pollinators compared to flower traits.

First data about Halictidae (Hymenoptera: Apoidea) in the region of Batna (Eastern Algeria) Investigations carried out on Halictidae bees in different localities in the region of Batna during the s...

Entomophilous and obligate out-crossing non-native plants need to become well integrated in the resident plant–pollinator network to set seeds and become established. However, it is largely unknown how pollination patterns differ between native ranges and those where plants have been introduced. We compared the identity, abundance and visitation rates of pollinators, insect pollen loads, pollen deposition on stigmas, and fruit and seed sets of Hedysarum coronarium, an entomophilous short lived N-fixing perennial, in populations from native and introduced ranges in Spain (South of mainland Spain and Menorca Island, respectively). In both areas, Hedysarum was visited by a similar number of species, mainly hymenopterans; seven species were common between native and introduced areas. However, pollinator richness, abundance, and visits per flower were greater in the native than in the introduced range, as were fruit and seed sets. Hedysarum pollen loads on stigmas and on Apis mellifera, the most common pollinator, did not differ between areas. Lower abundance of pollinators might be causing lower visitation rates, and to some extent reducing Hedysarum fruit and seed sets in the introduced area. Our biogeographical approach shows that integration of a non-native plant in a resident pollinator network does not prevent pollen limitation in the introduced area. Therefore, despite being necessary, pollination mutualistic relationships might not be the key for non-native plant establishment success in the introduced area.

IntroductionAposematism is a defense system against predators consisting of the toxicity warning using conspicuous coloration. If the toxin production and aposematic coloration is costly, only individuals in good physical condition could simultaneously produce abundant poison and striking coloration. In such cases, the aposematic coloration not only indicates that the animal is toxic, but also the toxicity level of individuals. The costs associated with the production of aposematic coloration would ensure that individuals honestly indicate their toxicity levels. In the present study, we examine the hypothesis that a positive correlation exists between the brightness of warning coloration and toxicity level using as a model the paper wasp (Polistes dominula).ResultsWe collected wasps from 30 different nests and photographed them to measure the brightness of warning coloration in the abdomen. We also measured the volume of the poison gland, as well as the length, and the width of the abdomen. The results show a positive relationship between brightness and poison-gland size, which remained positive even after controlling for the body size and abdomen width.ConclusionThe results suggest that the coloration pattern of these wasps is a true sign of toxicity level: wasps with brighter colors are more poisonous (they have larger poison glands).

Arthropods frequently use empty snail shells as shelter or nesting sites. This study analyses the use of shells from the arid-dwelling land snail Sphincterochila candidissima (Draparnaud 1801) by arthropods in the Sierra Elvira (south-eastern Spain). Arthropods of 11 different orders occupied 15.6% of shells. Salticidae (54.6%) and Apoidea (21.3%) comprised the majority of arthropods. Shells were used primarily when environmental temperatures were lowest, suggesting that, in the Sierra Elvira, arthropods use shells to escape from the cold. Weather explained 73% of the variation in shell occupation. However, Apoidea used shells independently of weather, occupying shells as nesting chambers. These results suggest that snail shells may be important refugia and nesting sites for arthropod fauna. Resume. Conditions meteorologiques et utilisation des coquilles vides de gasteropodes par les arthropodes. Les arthropodes utilisent frequement les coquilles vides d'escargots comme abris ou comme sites de nidifi cation. Cette etude analyse l'utilisation par les arthropodes des coquilles d'un escargot aridicole, Sphincterochila candidissima (Draparnaud 1801), dans la Sierra Elvira (sud-est de l'Espagne). Les arthropodes de 11 ordres differents ont ete trouves dans 15,6% des coquilles. Les Salticidae (54,6%) et les Apoidea (21,3%) constituaient la majorite des arthropodes. Les coquilles ont ete utilisees principalement lorsque la temperature de l'environnement etait basse. Cela suggere que, dans la Sierra Elvira, les arthropodes utilisent les coquilles pour echapper au froid. Les conditions meteorologiques expliquent 73% des variations d'occupation des coquilles observees. Toutefois, les Apoidea ont utilise les coquilles independamment du temps, en les occupant comme des chambres de nidifi cation. Ces resultats suggerent que les coquilles d'escargots peuvent etre importants comme refuges et comme sites de nidifi cation pour la faune d'arthropodes.

Study of recently collected bees from south-eastern Spain revealed a new species of subgenus Panurgus (Pachycephalopanurgus) Patiny, 1999, closely related to P. canescens Latreille, 1811, and P. calceatus Pérez, 1895. Within this group of three species, P. meridionalis sp.nov. is characterized by the presence of a pair of latero-ventral teeth on the third tergum of the male (unique among Panurginae). This new species is only the second species of Pachycephalopanurgus recorded from Europe, the other five being North African. Distributional patterns in subgenus Pachycephalopanurgus are mapped and summarized.