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Several studies have been devoted to analyze the association between spatial patterns of biological soil,crusts (BSC) and coverage of higher plants and, their conclusions are not always consistent. Knowing the interaction between BSC and vascular plants is crucial to understand the dynamics of the arid and semi-arid ecosystems. This research aims to know how the presence of the plant species Larrea tridentata, solar radiation and soil moisture influence the composition of BSC, under the hypothesis that the latter differs depending on those three factors. Three microsites were defined and simultaneously located at 20 randomly chosen points: under shrub east exposition (BAE), under shrub west exposition, (BAO) and area out of the canopy projection (FA). Morphotypes of the analyzed BSC (lichens, mosses, cyanobacteria, and liverworts) showed preferences to certain microsites. Lichens and mosses showed higher cover in sites underneath the plant. Lichens cover was about twice under L. tridentata than in areas without the plant cover. On average, mosses covered an area four times greater under the canopy of L. tridentata than in areas without plants. Cyanobacteria also showed greater coverage beneath the canopy, particularly in the west exposition (BAO). Both solar radiation and soil moisture showed differences between microsites. The results suggest that solar radiation is a relevant factor in CBS composition at the study area. Lichens, cyanobacteria and moss showed higher frequencies and coverage underneath L. tridentata than in open areas.