Astrophytum myriostigma cv. Kikko nudum

Geographic & Climate

• Geographic Coordinates: Cultivar origin: No wild type locality (Domesticated horticultural selection originating in Japan). Basal species Astrophytum myriostigma range: 21°40'N to 24°30'N, 99°40'W to 101°30'W (Central-Northern Mexico: San Luis Potosí, Nuevo León, Tamaulipas).

• Climate Classification: Cultivated lineage. Basal species occurs in BWh (Hot desert climate) transitioning to BSh (Hot semi-arid / steppe climate).

• Habitat Characteristics: Native data for this specific cultivar is non-existent as it arose solely under cultivation. The basal species thrives at 1,000–2,000 m above sea level, on alkaline limestone slopes and calcareous stony soils with scarce annual rainfall (250–400 mm) concentrated in summer.

Botanical Morphology

• Diagnostic Features: Characterized by acute, triangular, pointed outgrowths (tubercles) aligned along each rib margin, forming a distinctive saw-tooth or tortoiseshell relief. The epidermis is entirely glabrous ("nudum"), completely lacking the white flecks or trichome scales typical of the standard type. Areoles sit on the tips or notches of the tubercles and are spineless. Produces yellow, silk-lustered actinomorphic flowers (4–6 cm across) from the apical meristem.

• Growth Habit: Solitary, globose to shortly columnar with age. Winter-dormant (dry rest required below 10°C). Slow growth rate. Typically reaches 10–25 cm in height and 10–18 cm in stem diameter at maturity.

History & Etymology

• Etymology: Genus name Astrophytum derives from the Greek astron (star) and phyton (plant), describing the star-like rib symmetry. Specific epithet myriostigma comes from Greek myrios (countless) and stigma (mark/spot). Cultivar epithet 'Kikko' (亀甲) translates from Japanese as "turtle shell", referring to the geometric plates. 'Nudum' denotes the naked, unspotted epidermal surface.

• Historical Context: While wild A. myriostigma was first collected by Henri Galeotti in 1836 near San Luis Potosí, the 'Kikko' mutation was isolated and stabilized through selective hybridization and line-breeding by Japanese nurserymen in the late 20th century, becoming an iconic collectible in high-end succulent horticulture.