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Premise of the Study: Factors shaping spatiotemporal patterns of associations in mutualistic systems are poorly understood. We used the lichen-forming fungi Peltigera and their cyanobacterial partners Nostoc to investigate the spatial structure of this symbiosis at an intrabiome scale and to identify potential factors shaping these associations., Methods: Ninety-three thalli were sampled in Québec, Canada, along a south-north and an east-west transect of ~1300 km each. We identified the two main partners (Peltigera species and Nostoc phylogroups) using molecular markers and modeled the effects of environmental variables and partner occurrence on Peltigera-Nostoc distributions., Key Results: Peltigera species showed a high degree of specialization toward cyanobionts, whereas two Nostoc phylogroups dominated both transects by associating with several Peltigera species. Peltigera species had narrower ranges than these two main cyanobionts. Distributions of three Peltigera species were highly associated with precipitation and temperature variables, which was not detected for Nostoc phylogroups at this spatial scale., Conclusions: For these cyanolichens, factors driving patterns of symbiotic associations are scale dependent. Contrary to global-scale findings, generalist Peltigera species were not more widespread within the boreal biome than specialists. Nostoc availability was not the only driver of Peltigera species' geographic ranges; environmental factors also contributed to their intrabiome distributions. Climatic conditions (especially precipitation) limited the range of some Peltigera species more than the range of their cyanobacterial partners at an intrabiome (boreal) scale., (© 2018 Botanical Society of America.)

• Premise of this study: Aquatic cyanolichens from the genus Peltigera section Hydrothyriae are subject to anthropogenic threats and, therefore, are considered endangered. In this study we addressed the phylogenetic placement of section Hydrothyriae within Peltigera. We delimited species within the section and identified their symbiotic cyanobacteria.• Methods: Species delimitation and population structure were explored using monophyly as a grouping criterion (RAxML) and Structurama based on three protein-coding genes in combination with two nuclear ribosomal loci. The 16S and rbcLX sequences for the cyanobionts were analyzed in the broad phylogenetic context of free-living and symbiotic cyanobacteria.• Key results: We confirm with high confidence the placement of section Hydrothyriae within the monophyletic genus Peltigera; however, its phylogenetic position within the genus remains unsettled. We recovered three distinct monophyletic groups corresponding to three species: P. hydrothyria, P. gowardii s.s., and P. aquatica Miadl. & Lendemer, the latter being formally introduced here. Each species was associated with an exclusive set of Nostoc haplotypes.• Conclusions: The ITS region alone provides sufficient genetic information to distinguish the three morphologically cryptic species within section Hydrothyriae. Section Hydrothyriae seems to be associated with a monophyletic lineage of Nostoc, that has not been found in symbiotic association with other members of Peltigera. Capsosira lowei should be transferred to the genus Nostoc. Potential threats to P. aquatica should be re-examined based on the recognition of two aquatic species in western North America., (© 2014 Botanical Society of America, Inc.)

Background: The purpose of this study was to investigate the outcome of the naturalistic treatment of youth with Trichotillomania (TTM) in an anxiety disorders clinic sample., Methods: A retrospective chart review was conducted on 11 treated patients between the ages of 6 and 17, with DSM-IV TTM., Results: Ten patients were initially treated with a serotonin reuptake inhibitor (SRI), whereas one patient was initially treated with an antipsychotic. Three of the 10 patients who started with an SRI had a response (Clinical Global Impression-Improvement Scale (CGI-I)>or=2) in TTM symptoms. Nine patients of the 11 patients were treated with an antipsychotic medication (in 8 patients the antipsychotic was added after an initial trial with an SRI, in 1 patient the antipsychotic was the first line agent), 2 patients remained on an SRI; 8/9 were responders to antipsychotic treatment and 2 patients remitted (complete cessation of hair pulling). Adverse events to the SRI or antipsychotic were experienced by 7/11 patients but did not lead to treatment discontinuation., Conclusions: This retrospective case series suggests that youth with TTM maybe responsive to pharmacological interventions with SRIs and/or antipsychotic agents, although the response seemed to be more robust with antipsychotics. These preliminary findings will need to be replicated in a larger scale controlled design.