Coryphantha erecta

Structure and identification

Stems are cylindrical and branched, reaching about 50 cm tall in the monograph's descriptions, with a much smaller diameter. Tubercles are small, obliquely conical, flattened above and densely arranged. Thin yellowish lateral spines interweave over the surface. Central spine number varies, and they may be absent. Young tubercle axils contain white wool and brownish glands. Flowers are broad and yellow. [Dicht and Lüthy 2005, pp. 61]

Habitat and variation

The monograph documents the species in Hidalgo, Querétaro, Guanajuato and San Luis Potosí. It occurs on slopes with limestone gravel, among agaves and relatively open woody vegetation. Its slender stem and small, dense tubercles distinguish it from thick-stemmed coryphanthas that also branch. [Dicht and Lüthy 2005, pp. 61]

Water conduction in tubercles

The 2016 anatomical comparison covered 2 adult plants of this species, collected at natural sites during the rainy season. In the central vascular cylinder, vessels occurred in tissue rich in wide-band tracheids, whose walls have ring-like or spiral thickenings. Bundles reaching the tubercles contained vessel elements with smaller diameters than elements in the central cylinder. The authors proposed that this narrowing may restrict water flow to the tubercle. The assessment was based on preparations and cell dimensions, without direct flow measurements. [Terrazas et al. 2016, p. 2–8 PDF, tab. 1–2]

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