The red dwarf honey bee Apis florea Fabricius 1787, a single open comb constructing honey bee native to Asia, has been expanding its distributional range to Africa and Europe, and also reportedly intercepted in Western Australia. The first fully established colony of A. florea in Europe was found in Malta in 2024 near its shipping freeport to the south. The comb was collected, stored, and analysed morphometrically. The following morphometric measurements are reported in this paper: height and width of the comb; surface area of the comb (including crest, worker brood, and drone brood); depth, diameter, and volume of the cells (worker brood, drone brood, and crest); and the angle of the comb against the vertical. The cell measurements were concordant with other cell measurements found in the literature. These data might serve as a reference point for future studies, focusing on comparison of comb morphometry between native and introduced colonies.
For this study, mitochondrial-level research was conducted into the stingless bee species Lepidotrigona arcifera in order to assemble the complete mitogenome sequence of L. arcifera, analyze its structural characteristics, and provide a more reliable and valuable taxonomic basis for resolving the complex phylogeny of Meliponini tribe. We obtained the complete mitogenome of L. arcifera, spanning 15,260 bp in length and comprising thirteen protein-coding genes (PCGs), two ribosomal RNAs (rRNAs), twenty-two transfer RNAs (tRNAs), and a control region (D-loop). Phylogenetic analysis showed that L. arcifera has the closest genetic relationship with Lepidotrigona flavibasis (genus Lepidotrigona), followed by Lepidotrigona terminata (genus Lepidotrigona), and then Tetragonula pagdeni (genus Tetragonula), consistent with our previous findings. We further conducted a comparative analysis of structural variations across mitogenomes, revealing significant divergence in gene order and transcriptional orientation. The thirty-eight mitochondrial genes were categorized into four blocks (I-IV) and the D-loop. An inversion within Block IV distinguished L. arcifera from its closest relative L. flavibasis. Conserved block order was highly consistent within Melipona. Notably, Frieseomelitta varia (genus Frieseomelitta) and Tetragonisca angustula (genus Tetragonisca) formed a distinct clade and shared an identical block arrangement, which differed from other species. This study presents the first complete mitogenome sequence of L. arcifera, enriching the genomic resources for this taxon. More importantly, it reveals extensive mitochondrial gene rearrangements in stingless bees, suggesting that such structural variations represent valuable auxiliary molecular markers for stingless bee species classification.
\AbstractHoney bee colonies in the United States continue to experience health challenges driven by parasites, pathogens, and environmental stressors. To establish a statewide baseline for honey bee health in Utah, we conducted a multi pathogen and parasite survey of 429 feral and managed Apis mellifera colonies collected from seventeen counties across three major ecological regions between 2008 and 2021. Colonies were screened for Varroa destructor, Nosema apis, N. ceranae, Lotmaria passim, Crithidia mellificae, and the bacterial symbionts Spiroplasma apis and S. melliferum. Overall pathogen and parasite occurrence in Utah was low: N. ceranae and L. passim were each detected in 7.3% of colonies, while V. destructor was found in 9.0% of colonies screened. No samples were positive for N. apis, Crithidia spp., or either Spiroplasma species. Pathogen prevalence did not differ significantly between feral and non-migratory managed colonies, but strikingly low Varroa levels were observed in A-lineage feral colonies, with only one of forty-four colonies (2.3%) testing positive. Pathogens and parasites were detected across all ecological regions, although prevalence varied geographically and among mitochondrial DNA lineages. These results provide the first comprehensive assessment of pathogens and parasites in Utah honey bees, establish a critical baseline for future monitoring, and highlight the need for targeted studies investigating the potential mite resistance or reduced exposure of Utah's A-lineage feral populations.
Honey bees (Apis mellifera L.) may inhabit abandoned beehives in trees in the city and forests. Bees that naturally occupy abandoned nests, cavities, or hives are not managed by humans and are not treated for pathogens; consequently, they may be particularly susceptible to diseases. The aim of the study was to evaluate the prevalence of Lotmaria passim, Crithidia mellificae and Nosema spp. in free-living bee colonies through polymerase chain reaction (PCR). The study was conducted on samples of adult bees, pupae, larvae, bee bread and honey. The pathogens were detected in two samples. The predominant pathogen was L. passim, which was found in adult bees and four-day-old larvae. In addition, Nosema apis was found only in bees. The results of this study indicate that pathogens may be present in apparently healthy bee colonies and their larvae. Early detection of pathogens in adult bees and larvae can enhance the effectiveness of veterinary treatment in apiaries.
Varroa mites (Varroa destructor) are a major threat to honey bee health globally. Oxalic acid has gained popularity among beekeepers as a potential varroa mite control agent. This study evaluated the efficacy of oxalic acid vaporisation for managing varroa mites in field conditions in Taiwan. Twenty-four colonies of Italian honey bees (Apis mellifera ligustica) were divided into six groups, each consisting of four colonies: a control (no treatment), four treatment groups receiving two, four, six or eight oxalic acid treatments bi-weekly, and a group treated with Flumethrin strips (40 mg flumethrin/strip). Oxalic acid was vaporized at a rate of approximately 2 g per beehive. After thirty-five days, colonies receiving six and eight oxalic acid vaporisations showed significant reductions in varroa mite infestations, by 86% and 97%, respectively. Moreover, significantly higher worker bee mortality was observed in colonies receiving four, six, or eight oxalic acid vaporisations compared to the control. These findings suggest that six or eight oxalic acid (2 g/hive) vaporisations can effectively control varroa mite infestations in honey bees under field conditions, however beekeepers should be aware of potential impacts on worker bee mortality.
