October 21, 2018

Crassula for dummies like me - differences between C. capensis C. umbella and C. saxifraga

Crassula capensis, umbella and saxifraga (drawn from numerous resources)

Distribution:
C. capensis - Found in the south-western Cape Province from just south of Vanrhynsdorp southwards and west of the mountains to near Caledon; usually growing on exposed gravelly slopes or rarely in the shelter of rocks.
C.umbella -Richtersveld and W Karoo through Little Karoo to Humansdorp (NOT WCape!); Sheltered, rocky slopes Succulent Karoo
C. saxifraga - Northern Cape, Western Cape, Eastern Cape); stony flats/slopes or crevices, usually in Renosterveld

Leaves:
C. capensis - in 2 to 4 pairs max.6cm long usually only lower ones with petioles of up to 3 cm.
C. umbella and C. saxifraga have one or sometimes two pairs and no petiole.
C. umbella leaves cordatereniform or fused and amplexicaul also transversely depressed-obovate or more or less fused into a roundish umbrella-like structure around the stem. Up to 15cm.
C. saxifraga leaves flattened, transversely obovate, sessile and mostly pressed flat on the ground and leaves up to 12 cm.

Inflorescence:
C. capensis - umbellate to flat-topped thyrse, with peduncle 3–10 (-13) cm long, flowers 5–7(-12)-merous
C. umbella - elongate thyrse, rarely subumbellate, peduncle to 10 cm.
C. saxifraga - umbellate thyrses, peduncle to 25 cm.

Flowers :
Sepals:
C. capensis - glabrous, slightly fleshy, green often tinged red.
C. umbella - triangular lanceolate yellowish green
C. saxifraga - triangular, to 3 mm

Corolla:
C. capensis - star-shaped, scarcely fused at base, to 2 cm in diameter
C. umbella - stellate, to 1 cm
C. saxifraga -5-merous & tubular

Petals:
C. capensis - lanceolate, 3–6(-8) mm long, usually sharply acute, spreading, anthers brown.
C. umbella - lanceolate to ovate, to 4.5 mm, anthers yellow
C. saxifraga - oblanceolate, to 7.5 mm, tips subacute to rounded, spreading to recurved, anthers brown

Posted on October 21, 2018 18:15 by richardadcock richardadcock | 1 comment | Leave a comment

Archives