Xerophyte

Central Spines

Dark brown/grey to black, but also whitish or yellowish brown,1 to 4, up to 1.5(-2) cm long; the spines are close set, often interlacing, neatly arranged and give a comb-like effect. They're porrect or spreading, and straight.

Seeds

1.7-2.4 x 1.3-1.6 mm, keeled, brown, shiny, smooth; testa cells flat.

Description

Uebelmannia pectiniferaSN|14312]]SN|14312]] is a solitary cactus 10-50(-100) cm tall. It is a multiform species and very variable in habitat, comprising a complex of numerous local forms, where each form is linked to others by populations of plants with intermediate characteristics. Three subspecies are recognized, the nominate form (subsp. pectinifera), subsp. flavispina (Buining & Brederoo) P.J.Braun & Esteves and subsp. horrida (P.J. Braun) P.J. Braun & Esteves. The circumscription into subspecies possibly represents convenient over-simplification of the situation in nature.

Flowers

Diurnal, slender funnel-shaped greenish yellow. They are 8-16 mm long, 6-10(-12) mm in diameter. Tube to c. 8 mm, with triangular bract-scales, white hairs and bristles. Perianth-segments pale yellow, tinged reddish or greenish; style 6-7 mm; stigma-lobes 7-8.

Blooming Season

Flowers come sporadically from Early spring to Late Summer.

Ribs

13-40 (15 to 18 in subsp. pectinifera), acute, straight, vertical and prominent, not tuberculate, to 5 mm high and 5-7 mm broad.

Stem

Solitary or (rarely) aggregated, globular to fusiform or elongated or cylindrical, it is reported to grow to as much as 1 m tall and 10-15(-17) cm wide with gummiferous ducts under the epidermis. The epidermis is dark reddish-green to reddish-brown or green to grey-green, with or without waxy plates and rough. (In cultivation the colour of the plants depends on sun exposure, the plants grown in shadow are green with white stripes, while the ones in full sun take on a dark frost brown or purple colour) .

Radial Spines

Absent.

Fruits

Pear shaped to cylindrical, violet-red to bright pinkish, 1.5-2.5 cm long 6-8 mm wide, with few glabrescent or slightly woolly bract-scales.

Areoles

2 mm in diameter set closely (less than 3 mm apart), to form an almost continuous felt-like line down the ribs' sides, with sparse greyish or brownish wool when young, later glabrescent.