T. chiloensis var.eburneus is a fiercely spiny cactus with impressive and showy ivory spines.
 

This is the stouter spined form of T. chiloensis, nowadays this plant is not considered a distinct variety but only one of the variable phenotypes of this this clinal species.
 

Growth Habits: T. chiloensis var.eburneus is a fiercely spiny cactus. It develops into a shrub or small tree.
Stem: Rarely single, usually of several branches, sometimes of many, arising from near the base, starting nearly at right angles to the main trunk but soon erect, up to 8 m tall, stems 10-12.5 cm in diameter ; 10 to 17 low and broad ribs, separated by narrow intervals, divided into large tubercles even when fully mature.
Areoles/Spines: Areoles large whitish, 2 cm apart. Spines yellowish with brown tips, at least when young, greyish later; 1 to 4 centrals, porrect, often stout, 5-7 cm (or even 12 cm); 8 to 12 radials, up to 4 cm long.
Flowers: Nocturnal 14 cm. long, outer perianth-segments white but tinged with red or brown; inner perianth-segments white, acuminate.
Sun Exposure: Outside full sun or afternoon shade, inside needs bright light, and some direct sun.

Taxonomical notes:
The original name   for this cactus was Trichocereus chiloensis. In 1950, Skottsberg pointed that the name was misspelled, and was changed to "chilensis" for "Chile"+"ensis". The rules of nomenclature now, give priority to the original name, misspelling included, except if the name was changed by the original author. Thus, Friedrich & Rowley retained chiloensis when they included the genus Trichocereus into the genus Echinopsis.

Photo of conspecific taxa, varieties, forms and cultivars of Lobivia (Echinopsis) pentlandii .
 Of plants belonging to the Lobivia... complex (This Taxon has lots of synonyms (like most Lobivia) whit several controversial varieties and subspecies):

• Trichocereus chiloensis
• Trichocereus chiloensis var. eburneus
• Trichocereus chiloensis var. borealis

Scientific name: Trichocereus chiloensis (Colla) Britton & Rose, The Cactaceae; descriptions and illustrations of plants of the cactus family 2: 137-139, f. 199-200, 1920

Origin: North-Central Valley of Chile, from Curico to Puenta Colorado.

Synonyms:

• Echinopsis chiloensis (Colla) Friedrich & Rowley
• Cereus chilensis var. quisco,
• Trichocereus chiloensis var. zizkaanus,
• Cereus quisco,
• Trichocereus chiloensis var. quisco,
• Cereus chiloensis var. funkianus,
• Trichocereus funkii,
• Cereus funkii, Trichocereus chiloensis var. funkii,
• Cereus chiloensis var. eburneus,
• Eulychnia eburnea,
• Cereus chiloensis,
• Trichocereus chilensis,
• Cactus chiloensis,
• Trichocereus chiloensis var. eburneus,
• Cereus chiloensis var. zizkaanus
• Trichocereus chilensis (Colla) Fric & Kreuz. 1935
• Trichocereus chilensis var. eburneus (Phil.) W.T.Marshall 1941

The beautiful fang-like spines grow up from big felty areoles.