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The genus Dasylirion forms a group of well-represented perennial, dioecious species called "sotoles" in Mexico. This genus is a main component of the arid lands of northern Mexico and southern United States, and plays important ecological and economic roles. Four D. cedrosanum populations from northeastern Mexico were surveyed to gather statistics related to sex ratios and spatial distribution. The statistics were performed on an unbiased sample of 448 plants. Tests for sex ratio and spatial distribution were carried out. No evidence of departure from a 1:1 sex ratio proportion was found, both at the global level and within sampling sites. Patterns of spatial sex segregation were absent for all locations. One plant in the global sample could not be classified either as male or female, being anatomically andromonoecious. Both, the staminate and hermaphroditic flowers of this plant produced well-developed pollen. However, the hermaphroditic flowers were unable to produce fruits, even in the presence of pollen sources. The results are consistent with the expected for a well-established dioecious condition at the evolutionary scale, without environmental influences affecting the sex proportions and their spatial distribution.