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We report an arrestment response byBalaustium murorumthat is chemically mediated by excreta of conspecifics. Deutonymphs and adults arrest on saline extracts of their excreta and the excreta of each other. The arrestment could be mimicked by guanine, one of excreta’s principal components, but arrestment to it was lower than to excreta. Hypoxanthine, uric acid, xanthine, and adenine had arrestment properties, except for adenine in the adult. Adult appendages were removed by cauterizing. Without the palps, the adults did not arrest. Arrestment occurred with the first pair of legs removed, but with a decrease in response. Removal of the second pair of legs had no effect on arrestment. Thus, excreta act as an arrestant pheromone that allows mites to recognize suitable refuges under bark close to where pollen falls and arthropod prey are present. Detection of this arrestant pheromone occurs by using the palps and, to a lesser extent, the first pair of legs. [ABSTRACT FROM PUBLISHER]

Soil fungi were cultured from 24 wallows and proximal control sites in Maine and New Hampshire, USA during the autumn moose (Alces alces) breeding season of 2016 to investigate the presence of soil fungi pathogenic to winter tick larvae (Dermacentor albipictus). Twenty genera of fungi were isolated, and all are considered common in a forested ecosystem. The predominant genera isolated in wallows were pathogenic to winter tick larvae and included Aspergillus spp. (in particular A. flavus), Beauveria bassiana, Mortierella spp., Mucor spp., Paecilomyces spp., Penicillium spp., and Trichoderma spp. Wallow soils had specific characteristics and differed from proximal control sites by having: 1) lower fungal diversity, 2) a higher frequency of primary colonizers including Mortierella spp., Mucor spp., Penicillium spp., and Trichoderma spp., and 3) a more variable total amount of fungi indicative of changing (disturbed) soil conditions. We conclude that wallows are sites of soil disturbance that concentrate fungi known to be pathogenic to larval winter ticks. Fungi acquired by breeding moose using wallows might subsequently act as an on-host mechanism of tick control. [ABSTRACT FROM AUTHOR]