PCA analysis of the variables evaluated among the floral morphs of Opuntia streptacantha in Cadereyta de Montes, Queretaro, Mexico. Trait: a = corolla aperture set in FAA (mm), b = perianth segment length (mm), c = total flower length (mm), d = pericarp length (mm), e = pericarp width (mm), f = cladode length (cm), g = number of ovules, h = equatorial diameter of the ovarian chamber (mm), i = polar diameter of the ovarian chamber (mm), j = longest stamen length (mm), k = shortest stamen length (mm), l = anther-stigma distance (mm), m = style length (mm), n = number of pollen grains per anther, o = number of stamens, p = cladode width (cm), q = fruit length (cm), r = seed length (cm), and s = seed width (cm).