Synonymy
Phyllocactus anguliger Lemaire (1851) Jard. Fleur. 1, pl. 92
Phyllocactus serratus Brongnart in Labouret (1853) Monogr. Cact. 417
Phyllocactus angularis  Labouret (1853) Monogr. Cact. 511 sphalm.
Epiphyllum anguliger (Lemaire) G. Don in Loudon (1855) Encycl. Pl. ed. 3, 1380
Phyllocactus darrahii K. Schumann (1903) Gesamtb. Kakateenk. Nachtr. 69
Epiphyllum darrahii (K. Schumann) Britton & Rose (1913) Contr. U. S. Nat. Herb. 16:256
Epiphyllum beahmii hort. nom. nud.
Epiphyllum gertrudianum hort. nom. nud.
Epiphyllum anguliger v. darrahii Ewald. nom nud.
Epiphyllum anguliger v. pillocarpa Ewald nom. nud.
Epiphyllum anguliger v. pulocarpa Ewald nom.. nud.

Ethymology
This species is named for its deeply toothed stems which sometimes make a perfect rectangle .

History
This plant was first distributed by the Horticultural Society of London which obtained it from the collector, T. Hartweg, in 1846.

Origin and habitat
C & S Mexico (Jalisco, Nayarit, Colima, Guerrero and Matanego). Epiphytic in oak forests.

Systematics
A very variable species but rather distinct and recognition of subspecific taxa seems unnecessary. Most closely related to E. crenatum and E. lauii.

Cultivation
An easily cultivated, fast growing epiphyte. Needs a compost containing plenty of humus and sufficient moisture in summer. Should  be kept at 16-25ºC (61-77ºF), it may drop to 10-15ºC (50-59ºF) for shorter periods. Best grown in semi-shade. Flowers in late autumn or early winter.

Cultivars & hybrids
Disophyllum 'What Luck' (WC (REDC) 1997)
(E. anguliger x 'Bonanza Belle')
Persimon orange, darker at edges, outer tepals
rusty orange, overlapping, wide form. Style and stamens light orange. Small,
flat, deeply lobed stems.
ML Reg # 12184

E. anguliger 'Beahmianus'
Collected by Thomas MacDougall in 1967, in Oaxaca, Mexico. Flowers white with a lavenderpink throat.

E. anguliger 'Gertrudianus'
Flowers smaller than in most clones, 6-7,5 cm long.

Description
Stems profusely branched, primary stems terete at base, often woody, apical part and secondary stems flat and rather succulent, 20-30 cm long, 3-5 cm wide, deeply lobed, often to near midrib, the lobes rectangular to obtuse or rounded; areoles small nude or with 1-2 white britsles; epidermis green, smooth.
Flowers to 18cm long, 6-7 cm wide, nocturnal, strongly sweet-scented; pericarpel with podarias; receptacle 8-16 cm long, 4 mm thick, pale yellow, greenish or pinkish, bracteoles few, minute, linear and green, adpressed; outer tepals 10, linear to linear-lanceolate, acute, spreading or reflexed, 4-5 cm long, lemon yellow to brownish yellow; inner tepals lanceolate to ovate, acute or acuminate, white, sometimes toothed, as long as outer tepals; stamens white, erect to subdeclinate, nearly as long as tepals; style longer than inner tepals, white; stigma lobes 8-11, linear.
Fruit ovoid, brownish, greenish or yellowish, 3-4 cm thick.