裸蕚球屬植物，原產於阿根廷西北部。扁球形，頂部扁平，高10~30cm，直徑約30cm，是本屬植物最大者。外皮深綠色或藍綠色，稜不明顯，具有突起的球型小瘤塊。刺座有白色棉毛，中刺1~3支，側刺彎曲8~15支。刺長3~4cm，新刺紅至黑色，後轉為褐色。花白色至淺粉紅色，直徑2~3cm，常在莖頂環狀排列開放。夏季開花。

A Gymnocalycium species, native to northwestern Argentina. A globular cactus, flat at the apex, 10 - 30 cm high and 30 cm in diameter, the largest one in the genus. Outer skin dark green or blue-green, with small globose warts, ridges unapparent. White bristles grown on the areoles, 1 to 3 centrals and 8 to 15 bending radials. The spines can be 3 to 4 cm long, new ones are red to black initially, and then turn brown. Flowers white to pinkish, 2 - 3 cm in diameter, arranged in rings at the apex of the stem. Flowering in summer.

栽培：全日照通風環境下可生長良好，日照充足時可促進開花。炎夏時切勿讓植株曝曬，以免產生日燒等曬傷跡象。為了防止爛根等情形，需採用排水透氣且酸性的介質。是體型較大的仙人掌類植物，最好是隔年能換盆一次。

The plant grows well in full sun and ventilated conditions. Sufficient sun exposure can promote flowering, however, exposure in high summer may cause signs of scorch, such as sunburn. Plant in well-draining, breathable and acid soil to avoid root rotting. A large cactus species, advised to change pots every other year.

觀賞刺與花的種類。因為刺粗硬略具危險性，須擺放於不易觸及的位置。單株可用陶瓦盆種植，以彰顯樸實的形貌。果實可以食用。

It’s an ornamental cactus valued for the spines and flowers. Advised to put it in a safe place to avoid people touching the dangerous spines. Suitable for single planting in pottery pots to accentuate the earthy look. Fruit edible.