Xerophyte

Central Spines

1 to 7 grey to reddish vertical and straight-projecting, 2-7 cm long.

Seeds

1,6-2,7 mm long and o,6-1,7 mm wide, testa cells tabular net patterned with a verrucose surface sculpture.

Description

Thelocactus tulensisSN|1065]]SN|1065]] is a globular and strongly tubercled cactus with larger white to puple flowers. It is a very variable polymorphic species which comprises innumerable geographical forms linked one to each others by populations of plants with intermediate characteristics. Such variations has led to establishment of several unnecessary names for this species.

Roots

Fat underground tap root.

Tubercles

Plump, very prominent, but quite variable in shape and size, 10-30 mm wide and 12-25 mm tall, conical rounded or somewhat angular in cross section.

Flowers

Diurnal, silver white, pink or purple with darker mid-stripes, 2,5-5 cm long and 3,5-8 cm wide. Tube very short.

Spines

Acicular, straw coloured, whitish or brownish red, becoming grey with age, evenly distributed on the stem, straight to twisted, flattened.

Ribs

8 to 13 strongly tuberculate with small distinct connecting ribs between tubercles of the same vertical row.

Stem

Depressed to globose (or somewhat elongated in cultivation), 2,5-25 cm tall, 6-18 in diameter, glaucous green, dark olive green, brownish or magenta and strongly tuberculate.

Fruits

Spherical to oblong up to 10 cm in diameter, green to brown opening by basal pore.

Habit

Thelocactus tulensisSN|1065]]SN|1065]] is a geophyte succulent plant simple or branching at the top and sides when old, and sometime abundantly cespitose

Blooming Season

Early summer.

Radial Spines

4 to 12 radiating straight or more or less recurved, 7-15 mm long.

Areoles

2-9 mm long, 2-6 mm wide, 12-35 mm apart, with partially developed grooves,without nectar secreting glands.