When mating interactions are influenced by multiple sources of selection, they may involve multiple stages of mate assessment. At each stage, a different set of morphological and behavioural traits may be important in determining the outcome of the interaction. Here, we test the potential for multiple sources of selection to shape mating interactions in Leiobunum vittatum harvestmen, commonly known as ‘daddy longlegs’. We provide a qualitative and quantitative study of mating interactions, and investigate the influence of multiple morphological traits on each of several distinct stages of their mating interactions. Mating interactions start with a struggle between males and females during which the male attempts to secure the females in a mating embrace. Success at this stage depends on the length of the male’s clasping pedipalps: those with shorter pedipalps (and thus greater mechanical advantage) were more successful. Male size relative to the female determines how quickly males achieve this embrace. Mating interactions then proceed to tactile exchanges between males and females, indicating the potential for mutual mate choice and/or peri- and post-copulatory selection. We found no morphological predictors of the timing of these later stages of the mating interactions, and suggest that the exchange of a nuptial gift is important for the dynamics of these stages. Overall, our results highlight L. vittatum as a potentially highly informative group for studying how traits involved in mating are shaped by the interaction of selection across multiple stages in mating interactions.

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A new species of a gregarious Meteorus wasp (Braconidae) constructs an unusual cocoon mass. Meteorus restionis sp. n. is described and distinguished from similar species. Cocoons of M. restionis are dark-brown, ovoid, and they are attached perpendicularly by their posterior end along a long, suspended cable. Th e cable is formed by intertwined, independent threads which are glued together at irregular intervals along its length, suggesting a certain degree of cooperation or at least tolerance among larvae during the construction of the cable. Intertwining and gluing the individual threads in a single cable presumably gives it a greater resistance against wind and other environmental stress. Prior to emergence the wasp cuts a neat, circular cap at the anterior end of its cocoon, and the cap remains attached by some threads to the rest of the cocoon.

The foraging behaviour of social insects is highly flexible because it depends on the interplay between individual and collective decisions. In ants that use foraging trails, high ant flow may entail traffic problems if different workers vary widely in their walking speed. Slow ants carrying extra‐large loads in the leaf‐cutting ant Atta cephalotes L. (Hymenoptera: Formicidae) are characterized as ‘highly‐laden’ ants, and their effect on delaying other laden ants is analyzed. Highly‐laden ants carry loads that are 100% larger and show a 50% greater load‐carrying capacity (i.e. load size/body size) than ‘ordinary‐laden’ ants. Field manipulations reveal that these slow ants carrying extra‐large loads can reduce the walking speed of the laden ants behind them by up to 50%. Moreover, the percentage of highly‐laden ants decreases at high ant flow. Because the delaying effect of highly‐laden ants on nest‐mates is enhanced at high traffic levels, these results suggest that load size might be adjusted to reduce the negative effect on the rate of foraging input to the colony. Several causes have been proposed to explain why leaf‐cutting ants cut and carry leaf fragments of sizes below their individual capacities. The avoidance of delay in laden nest‐mates is suggested as another novel factor related to traffic flow that also might affect load size selection The results of the presennt study illustrate how leaf‐cutting ants are able to reduce their individual carrying performance to maximize the overall colony performance.