https://opendata.uni-halle.de//handle/1981185920/35798 2026-04-09T19:29:52Z 2026-04-09T19:29:52Z Seidelmann, Karsten https://opendata.uni-halle.de//handle/1981185920/39105 2026-02-03T11:54:41Z 2021-10-19T00:00:00Z

Title: Territoriality is just an option: allocation of a resource fundamental to the resource defense polygyny in the European wool carder bee, Anthidium manicatum (Hymenoptera: Megachilidae) Author(s): Seidelmann, Karsten Abstract: The wool carder bee Anthidium manicatum is one textbook example of resource defense polygyny among solitary bees, known for intense male–male competition, forced copulations, and the extreme form of interspecific territoriality toward other flower visitors. This mating system depends on the spatial structure of the defended resource and requires several adaptations in males. The allocation of patches with host plants as well as male body size and phenology was analyzed over 3 years in the diverse habitat of a botanical garden. Anthidium manicatum males searched in groups up to 12 individuals a wide diversity of patches with various food plants of foraging females. Territories were established in small high-quality patches only. Males abandoned aggressive and territorial behavior in large patches. Available patches were occupied by males of the various body size fractions independently of each other according to patch profitability. The higher competitive weight of large males in small patches compared to spacious ones was balanced by an opposing correlation of patch profitability. Although the mating system in A. manicatum is clearly a resource defense polygyny, males were found to be plastic in their behavior, and territoriality was not consistently observed. Mate acquiring tactics, be they territory holder (bourgeois), sneaker, floater, or scrambler for mating, can be considered to be different behavioral phenotypes within one environmentally sensitive conditional strategy.

2021-10-19T00:00:00Z Frahnert, Konrad Sebastian Seidelmann, Karsten https://opendata.uni-halle.de//handle/1981185920/39104 2026-02-03T11:54:39Z 2021-10-19T00:00:00Z

Title: Individual Scent-Marks of Nest Entrances in the Solitary Bee, Osmia cornuta (Hymenoptera: Apoidea) Author(s): Frahnert, Konrad Sebastian; Seidelmann, Karsten Abstract: The ability to recognize the own nest is a basic skill in nest constructing solitary bees. Osmia cornuta females use a dual mechanism of visual orientation to approach a nest and olfactory verification of the tube when entering it. Occupied tubular cavities were steadily marked by the resident female. Nest marking substances originate from Dufour’s gland and cuticle, enriched by external volatiles. Scent tags were dominated by alkanes and alkenes in a species-specific mixture enriched by small amounts of fatty acid esters, alcohols, and aldehydes. The individual nest tags are sufficiently variable but do not match perfectly with the nesting female. Furthermore, tags are not consistent over time, although females continue in marking. Besides the correct position of the entrance in space, bees have to learn also the bouquet of the used cavity and update their internal template at each visit to recognize their own nest by its actual smell. Due to the dominance of the species-specific hydrocarbon pattern, nest marks may function not only as an occupied sign but may also provide information on the species affiliation and constitution of the nest owner.

2021-10-19T00:00:00Z Tehel, Anja Vu, Quynh Bigot, Diane Gogol-Döring, Andreas Koch, Peter Jenkins, Christina Doublet, Vincent Theodorou, Panagiotis Paxton, Robert J. https://opendata.uni-halle.de//handle/1981185920/35852 2026-02-03T11:54:40Z 2019-01-29T00:00:00Z

Title: The two prevalent genotypes of an emerging infectious disease, deformed wing virus, cause equally low pupal mortality and equally high wing deformities in host honey bees Author(s): Tehel, Anja; Vu, Quynh; Bigot, Diane; Gogol-Döring, Andreas; Koch, Peter; Jenkins, Christina; Doublet, Vincent; Theodorou, Panagiotis; Paxton, Robert J. Abstract: Deformed wing virus (DWV) is an emerging infectious disease of the honey bee (Apis mellifera) that is considered a major cause of elevated losses of honey bee colonies. DWV comprises two widespread genotypes: the originally described genotype A, and genotype B. In adult honey bees, DWV-B has been shown to be more virulent than DWV-A. However, their comparative effects on earlier host developmental stages are unknown. Here, we experimentally inoculated honey bee pupae and tested for the relative impact of DWV-A versus DWV-B on mortality and wing deformities in eclosing adults. DWV-A and DWV-B caused similar, and only slightly elevated, pupal mortality (mean 18% greater mortality than control). Both genotypes caused similarly high wing deformities in eclosing adults (mean 60% greater wing deformities than control). Viral titer was high in all of the experimentally inoculated eclosing adults, and was independent of wing deformities, suggesting that the phenotype ‘deformed wings’ is not directly related to viral titer or viral genotype. These viral traits favor the emergence of both genotypes of DWV by not limiting the reproduction of its vector, the ectoparasitic Varroa destructor mite, in infected pupae, and thereby facilitating the spread of DWV in honey bees infested by the mite.

2019-01-29T00:00:00Z Fleischer, Jörg Krieger, Jürgen https://opendata.uni-halle.de//handle/1981185920/35851 2026-02-03T11:54:41Z 2018-11-20T00:00:00Z

Title: Insect pheromone receptors : key elements in sensing intraspecific chemical signals Author(s): Fleischer, Jörg; Krieger, Jürgen Abstract: Pheromones are chemicals that serve intraspecific communication. In animals, the ability to detect and discriminate pheromones in a complex chemical environment substantially contributes to the survival of the species. Insects widely use pheromones to attract mating partners, to alarm conspecifics or to mark paths to rich food sources. The various functional roles of pheromones for insects are reflected by the chemical diversity of pheromonal compounds. The precise detection of the relevant intraspecific signals is accomplished by specialized chemosensory neurons housed in hair-like sensilla located on the surface of body appendages. Current data indicate that the extraordinary sensitivity and selectivity of the pheromone-responsive neurons (PRNs) is largely based on specific pheromone receptors (PRs) residing in their ciliary membrane. Besides these key elements, proper ligand-induced responses of PR-expressing neurons appear to generally require a putative co-receptor, the so-called “sensory neuron membrane protein 1” (SNMP1). Regarding the PR-mediated chemo-electrical signal transduction processes in insect PRNs, ionotropic as well as metabotropic mechanisms may be involved. In this review, we summarize and discuss current knowledge on the peripheral detection of pheromones in the olfactory system of insects with a focus on PRs and their specific role in the recognition and transduction of volatile intraspecific chemical signals.

2018-11-20T00:00:00Z