Subspecies, varieties, forms and cultivars of plants belonging to the Mammillaria elongata group

• Mammillaria elongata DC.: It forms a tight clumps of erect, ascending, prostrate or recumbent stems. It occurs in more variations than any other Mammillaria species for colour and spine variations.
• Mammillaria elongata f. cristata hort.: Crested form. Garden origin.
• Mammillaria elongata subs. echinaria (DC.) D.R.Hunt: It is different in that it has 2-3 dark central spines. Unlike the subspecies 'elongata' which has none or very short central spines if any.
• Mammillaria elongata f. monstruosa: Slow growing plant with almost spineless stems. Only a few spines are produced at the base of new growing stems. It will form with time an irregular clump of stems.
• Mammillaria elongata cv. Kopper King: It has showy copper colored spines on the top. The pale yellow flowers contrast with the dark coloured spines.