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Larval populations of Clunio sp.1 are reported for the first time from marine fouling samples obtained in Hurghada during November 2015. This is a new record for the Egyptian Red Sea fauna. A full structural description of the larva is provided and its local distribution is discussed. [ABSTRACT FROM AUTHOR]

We present a biologically plausible dynamics model to simulate swarms of flying insects. Our formulation, which is based on biological conclusions and experimental observations, is designed to simulate large insect swarms of varying densities. We use a force-based model that captures different interactions between the insects and the environment and computes collision-free trajectories for each individual insect. Furthermore, we model the noise as a constructive force at the collective level and present a technique to generate noise-induced insect movements in a large swarm that are similar to those observed in real-world trajectories. We use a data-driven formulation that is based on pre-recorded insect trajectories. We also present a novel evaluation metric and a statistical validation approach that takes into account various characteristics of insect motions. In practice, the combination of Curl noise function with our dynamics model is used to generate realistic swarm simulations and emergent behaviors. We highlight its performance for simulating large flying swarms of midges, fruit fly, locusts and moths and demonstrate many collective behaviors, including aggregation, migration, phase transition, and escape responses. [ABSTRACT FROM AUTHOR]

Vespula germanica is a social wasp that has become established outside its native range in many regions of the world, becoming a major pest in the invaded areas. In the present work we analyze social communication processes used by V. germanica when exploiting un-depleted food sources. For this purpose, we investigated the arrival pattern of wasps at a protein bait and evaluated whether a forager recruited conspecifics in three different situations: foragers were able to return to the nest (full communication), foragers were removed on arrival (communication impeded), or only one forager was allowed to return to the nest (local enhancement restricted). Results demonstrated the existence of recruitment in V. germanica, given that very different patterns of wasp arrivals and a higher frequency of wasp visits to the resource were observed when communication flow between experienced and naive foragers was allowed. Our findings showed that recruitment takes place at a distance from the food source, in addition to local enhancement. When both local enhancement and distant recruitment were occurring simultaneously, the pattern of wasp arrival was exponential. When recruitment occurred only distant from the feeder, the arrival pattern was linear, but the number of wasps arriving was twice as many as when neither communication nor local enhancement was allowed. Moreover, when return to the nest was impeded, wasp arrival at the bait was regular and constant, indicating that naive wasps forage individually and are not spatially aggregated. In conclusion, this is the first study to demonstrate recruitment in V. germanica at a distance from the food source by modelling wasps’ arrival to a protein-based resource. In addition, the existence of correlations when communication was allowed and reflected in tandem arrivals indicates that we were not in the presence of random processes. [ABSTRACT FROM AUTHOR]

In social insects, secretions of the exocrine gland may modulate their behavior. Although many glands have their functions elucidated, this is absent for the intramandibular glands in ants. To study the function of intramandibular gland secretions in the antNeoponera villosa, its compounds were subjected to behavioral analyses. These analyses revealed a significant increase in the walking time of ants exposed to the nestmate mandible extract. The results suggest that intramandibular gland compounds ofN. villosamay play the role of alarm or scent trial pheromones. [ABSTRACT FROM AUTHOR]

Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities at 10:00, 13:00, and 16:00 hours than at 07:00 hours. Thrips densities did not differ among blocks at the budding stage, but they did at peak flowering and podding stages. Dispersion indices suggested that both male and female BFTs were aggregated. Active male aggregation occurred only on green plant parts and it varied across blocks, crop stages, and locations. Similarly, active female aggregation was observed in peak flowering and podding stages. Such active aggregation indicates a semiochemical or behaviour-mediated aggregation. Identification of such a semiochemical may offer new opportunities for refining monitoring and management strategies for BFT on cowpea, the most important grain legume in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

During the mating season, honeybee males, the drones, gather in congregation areas 10-40 m above ground. When a receptive female, a queen, enters the congregation, drones are attracted to her by queen-produced pheromones and visual cues and attempt to mate with the queen in mid-air. It is still unclear how drones and queens find the congregations. Visual cues on the horizon are most probably used for long-range orientation. For shorter-range orientation, however, attraction by a drone-produced aggregation pheromone has been proposed, yet so far its existence has not been confirmed conclusively. The low accessibility of congregation areas high up in the air is a major hurdle and precise control of experimental conditions often remains unsatisfactory in field studies. Here, we used a locomotion compensator-based walking simulator to investigate drones' innate odor preferences under controlled laboratory conditions. We tested behavioral responses of drones to 9-oxo-2-decenoic acid (9-ODA), the major queen-produced sexual attractant, and to queen mandibular pheromone (QMP), an artificial blend of 9-ODA and several other queen-derived components. While 9-ODA strongly dominates the odor bouquet of virgin queens, QMP rather resembles the bouquet of mated queens. In our assay, drones were attracted by 9-ODA, but not by QMP. We also investigated the potential attractiveness of male-derived odors by testing drones' orientation responses to the odor bouquet of groups of 10 living drones or workers. Our results demonstrate that honeybee drones are attracted by groups of other drones (but not by workers), which may indicate a role of drone-emitted cues for the formation of congregations. [ABSTRACT FROM AUTHOR]

Densities of two allochronic, geographically overlapping populations of periodical cicadas were censused in the eggnest stage in order to test the hypothesis that larger populations can be supported when the root-feeding nymphs are of different ages. In a frequently burned chest-high stand of scrub oak (Quercus ilicifolia) on Long Island, Magicicada septendecim emerged in 1974 (Brood XIV), then again in 1978 (Brood I) from under the same individual plants over an area of about 1.2 x 3.5 km. Adjacent to this, in the same vegetation, periodical cicadas emerged in 1974 but not in 1978. A nested scheme of sampling revealed significantly higher total eggnest densities when Broods I and XIV occupied the same ground than when Brood XIV existed by itself. The major component of variation in density was among quadrats within plots. That is, cicadas exhibited patchiness on a small scale (metres) which was not reflected in patchiness on a larger scale (tens of metres). Microspatial distributions were thus patchy in both Brood I and XIV, yet dense patches of one brood were usually not correlated with dense patches of the other. Apparently the vegetation appears about as uniform to the cicadas as it does to the human observer, the primary cause of the patchy oviposition pattern being either mutual attraction among oviposition females or lack of dispersal from the chorusing and mating centers. The degree of patchiness is inversely density-dependent, in that the most patchy distributions were invariably those with lowest density. However, several plots with low density were not very patchy. This pattern makes biological sense, remembering that mutual attraction cannot operate unless the animals perceive one another, and at low densities they may sometimes do so and sometimes not. Further analysis, plotting mean crowding against mean density (following Iwao 1968) suggests that mutual attraction among females is weakened at high densities. As modes of data analysis, both kinds of plots-mean crowding vs. mean density and patchiness vs. mean density-bring out patterns that would not otherwise be apparent. In this connection, we offer an empirical definition for the concept, density-independent aggregation." [ABSTRACT FROM AUTHOR]