Trachymyrmex septentrionalis ant microbiome assembly is unique to individual colonies and castes.

Within social insect colonies, microbiomes often differ between castes due to their different functional roles, and between colony locations. Trachymyrmex septentrionalis fungus-growing ants form colonies throughout the eastern USA and Northern Mexico that include workers, female and male alates (unmated reproductive castes), larvae, and pupae. How T. septentrionalis microbiomes vary across this geographic range and between castes is unknown. Our sampling of individual ants from colonies across the Eastern USA revealed a conserved core T. septentrionalis worker ant microbiome, and that worker ant microbiomes are more conserved within colonies than between them. A deeper sampling of individual ants from two colonies that included all available castes (pupae, larvae, workers, female and male alates), from both before and after adaptation to controlled laboratory conditions, revealed that ant microbiomes from each colony, caste, and rearing condition were typically conserved within but not between each sampling category. Tenericute bacterial symbionts were especially abundant in these ant microbiomes and varied widely in abundance between sampling categories. This study demonstrates how individual insect colonies primarily drive the composition of their microbiomes, and that these microbiomes are further modified by developmental differences between insect castes and the different environmental conditions experienced by each colony.

Biomarkers in a socially exchanged fluid reflect colony maturity, behavior and distributed metabolism

In cooperative systems exhibiting division of labor, such as microbial communities, multicellular organisms, and social insect colonies, individual units share costs and benefits through both task specialization and exchanged materials. Socially exchanged fluids, like seminal fluid and milk, allow individuals to molecularly influence conspecifics. Many social insects have a social circulatory system, where food and endogenously produced molecules are transferred mouth-to-mouth (stomodeal trophallaxis), connecting all the individuals in the society. To understand how these endogenous molecules relate to colony life, we used quantitative proteomics to investigate the trophallactic fluid within colonies of the carpenter ant Camponotus floridanus. We show that different stages of the colony life cycle circulate different types of proteins: young colonies prioritize direct carbohydrate processing; mature colonies prioritize accumulation and transmission of stored resources. Further, colonies circulate proteins implicated in oxidative stress, ageing, and social insect caste determination, potentially acting as superorganismal hormones. Brood-caring individuals that are also closer to the queen in the social network (nurses) showed higher abundance of oxidative stress-related proteins. Thus, trophallaxis behavior could provide a mechanism for distributed metabolism in social insect societies. The ability to thoroughly analyze the materials exchanged between cooperative units makes social insect colonies useful models to understand the evolution and consequences of metabolic division of labor at other scales.

Three new species of the genus Proctotydaeus (Acari: Iolinidae) associated with Brazilian stingless bees

Proctotydaeus (Acari: Iolinidae) species live in bird nests, insect colonies, plants and barn straw, and comprise 17 species belonging to four subgenera. Here, we report three new species of Proctotydaeus mites living inside stingless bee colonies in Brazil. Proctotydaeus (Neotydeolus) lasaroi Da-Costa, Rodighero & Ferla sp. nov., Proctotydaeus (Oriolella) dorsoreticulatus Da-Costa, Rodighero & Ferla sp. nov. and Proctotydaeus (Oriolella) quadrifasciatae Da-Costa, Rodighero & Ferla sp. nov. are described and illustrated based on specimens collected from three species of stingless bees in the state of Rio Grande do Sul, Brazil.

Asian Giant Hornet Vespa mandarinia Smith (1852) (Insecta: Hymenoptera: Vespidae)

Vespa mandarinia Smith, commonly called the Asian giant hornet, is the largest hornet in the world. Its size and distinctive markings make it easily distinguishable from other Asian hornet species. Not only is the wasp occasionally life-threatening to humans, it can decimate a number of insect colonies, most notably wild and farmed honey bees. Vespa mandarinia is native to Japan and occurs in several countries in Asia. The first Vespa madarinia hornet detected in the United States was in Washington State in 2019. This 5-page fact sheet written by Caitlin Gill, Cameron Jack, and Andrea Lucky and published by the UF/IFAS Entomology and Nematology Department describes the hornet, its biology, its predatory strategies, and its medical significance. The fact sheet also provides some strategies for management of this dangerous and destructive hornet.https://edis.ifas.ufl.edu/in1281