Mammillaria laui

Mammillaria laui is a species of cactus in the genus Mammillaria, native to Tamaulipas state in Mexico.^[2] A number of subspecies were described, occurring along an elevation gradient; these are no longer accepted.^[2] It is listed as Critically Endangered (CR) in the wild.^[1]

Mammillaria laui
In bloom
Individuals tend to form clumps over time
Conservation status
Critically Endangered  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Cactaceae
Subfamily:	Cactoideae
Genus:	Mammillaria
Species:	M. laui
Binomial name
Mammillaria laui D.R.Hunt
Synonyms[2]
List Escobariopsis laui (D.R.Hunt) Doweld 2000 Escobariopsis laui subsp. dasyacantha (D.R.Hunt) Doweld 2000 Escobariopsis laui subsp. subducta (D.R.Hunt) Doweld 2000 Mammillaria laui subsp. dasyacantha (D.R.Hunt) D.R.Hunt 1997 Mammillaria laui f. dasyacantha D.R.Hunt 1979 Mammillaria laui f. subducta D.R.Hunt 1979 Mammillaria laui subsp. subducta (D.R.Hunt) D.R.Hunt 1997 Mammillaria subducta (D.R.Hunt) Repp. 1989 Mammillaria subducta var. dasyacantha (D.R.Hunt) Repp. 1989

Description

Mammillaria laui grows solitary in depressed, spherical or spurring shapes, reaching up to 6 centimeters in height and 4.5 centimeters in diameter. Its densely packed, bulbous-conical warts are dark green, non-lacerating, and may have sparse wool in the axils or be bare. The plant features 30 to 40 fine, bristle-like radial spines that are 4 to 8 millimeters long, glassy white, irregularly radiating, and protrude outward, covering the body. It also has 5 to 8 central spines, slightly thicker than the radial spines, measuring 6 to 7 millimeters long, protruding, and yellow with a bulbous, thickened base.

The flowers are broadly funnel-shaped, about the same diameter as the plant, and measure 1.6 to 2 centimeters in length. They are bright carmine pink. The whitish fruits are spherical to oblong, small (2 to 6 millimeters long), and contain black seeds.^[3]

Distribution

This species is found between Ciudad Victoria and Jaumave in the Mexican state of Tamaulipas, where it inhabits mountainous regions between 800 and 1700 meters elevation.^[4]

Taxonomy

Mammillaria laui was first described in 1979 by David Richard Hunt. The name honors the German cactus researcher Alfred Bernhard Lau.^[5]

As Mammillaria lauii it has gained the Royal Horticultural Society's Award of Garden Merit.^[6]