Recent work indicates clinically meaningful differences in domains of psychopathic personality -- such as grandiose-manipulative (GM), callous-unemotional (CU), and daring-impulsive (DI) traits -- and parenting factors. Yet, different domains of parenting and reports from multiple informants may vary in their associations to psychopathic traits. This study examined psychopathic traits and their links with parental monitoring behaviors, parental knowledge, and adolescent disclosure. Further, we evaluated whether adolescents' self-reported resting arousal moderated these associations. A mixed clinic-referred/community sample of 134 adolescent-parent dyads (M[subscript age] = 14.49; SD = 0.50; 66.4% female) completed multi-dimensional measures of psychopathy, parental monitoring behaviors, parental knowledge, and adolescent disclosure; adolescents also self-reported on their resting arousal. Results indicated links between: (a) increased parent-reported GM traits and decreased parent-reported parental knowledge, and (b) increased parent-reported DI traits and lower parent-reported monitoring behaviors, which were attenuated at high levels of adolescent-reported resting arousal. Associations between elevated dimensions of psychopathic traits and lower levels of parental monitoring behaviors, parental knowledge, and adolescent disclosure were most consistent within-informants, with some cross-informant associations identified for links between elevated GM and DI and lower levels of parental monitoring behaviors and parental knowledge. These findings have important implications for our understanding of how to assess and prevent psychopathy and associated externalizing problems, and suggest that targeting modifiable environmental and psychophysiological factors may be particularly important.