Xerophyte

Central Spines

0-1(-4) per areole, angular, (0-)50-120 mm long.

Description

In general it is a mounding cactus, forming bulbous piles of from a few to hundreds of spherical to cylindrical stems. Plants may vary from densely spiny (usually) to no spines at all. Echinocereus triglochidiatusSN|7140]]SN|10576]] is the most wide-spread of the Echiniocereus species and is also the most variable in appearance. In fact, the several varieties are so different-looking that the only uniting factor is the bright red bloom and rounded petals.

Taxonomy

A distinct species with two subspecies, the nominate form and subsp. mojavensis (Engelm. & J.M.Bigelow) L.D.Benson.

Note

A spineless form (var. inermis) has been applied at various taxonomic ranks to individual plants with spines absent or nearly so in the eastern portion of var. mojavensis, mainly found in the mountains and mesas of western Colorado and eastern Utah. On these plants, areoles may have very few spines and some stems can be almost completely spineless, but the same plant will have spined stems and many spines per areole in another area.

Flowers

Diurnal, funnel-shaped, 5-10 × 3-7 cm; flower tube 20-35 mm; flower tube hairs 1-2 mm; inner tepals bright orange-red to dark red, proximally paler (bases sometimes yellow or white), 25-40 × 10-15 mm, tips thick and rigid; anthers usually pink to purple. There is a thick nectar chamber and many thready pink stamens at the center of the corolla. The flowers are pollinated by hummingbirds.

Blooming Season

Apr-June, the flowers remain open for 2 or 3 days. Blooming generally begins 5 to 10 years after sowing, as the plant matures.

Chromosome Number

E. triglochidiatus is consistently diploid (2n = 22), apart from the tetraploid (2n = 44) Echinocereus coccineusSN|10576]]SN|7140]] Engelm., which has been treated as conspecific by some previous authors (Benson, 1982; Taylor, 1985). The var. triglochidiatus has been previously reported as var. gonacanthus (Engelm. & Bigelow) Boissevain and perhaps under other names as well.

Ribs

5-8 or 8-12, crests slightly undulate (some populations contain plants with strongly interrupted ribs).

Stem

Usually erect, spherical or cylindrical, 3-70 cm tall, 5-13 cm in diameter.

Radial Spines

(0-)1-10 per areole, (0-)15-90 mm long; Spines are at first yellow, pink or black.

Fruits

Juicy, with deciduous spines, and edible, green to yellow-green or pink (rarely red), (15-)20-35 mm, pulp white, fruiting 2-2.5 months after flowering.

Areoles

10-40 mm apart, and somewhat woolly.Spines (0-)3-11 per areole, with central spines being difficult to distinguish from the radial spines. Straight to curved or contorted, appressed (radial spines) or spreading to projecting outward (some radials, and central spines when present), white to yellow, grey, or sometimes nearly black, but those turn whitish-grey after their first season.