Gastrolobium graniticum  |  

Gastrolobium graniticum, Family Papilionaceae / Fabaceae, also known as Granite Poison, is
an erect open shrub, growing to 2.5 m tall, with ascending, angular, sparsely to moderately
pubescent branchlets. The branches are purple. The petioles, 5Ð7 mm long, are terete and
continuous but not decurrent with the branchlet. The spreading leaves are opposite, 48Ð62 mm
long, 19Ð32 mm wide, and elliptic to rarely obovate shaped. The leaves have prominently
reticulate venation, a rounded apex and slightly undulated margins. The stipules are erect and
narrowly triangular to hyaline, and to 2Ð3 mm long. The inflorescences consist of more than
30 flowers at the ends of branches. The flowers are yellow-orange in colour with a red ring
surrounding the yellow centre. The calyx, 6Ð8 mm long, is hairless and has two upper and
three lower lobes, which are all usually curved. The upper lobes, 2Ð4 mm long, are sometimes
straight and united higher than the lower lobes. The lower lobes are triangular and are about
3 mm long. The corollas are reflexed and transversely ovate, growing 13Ð15 mm long and
15.5Ð16.5 mm wide, with claws that are 4Ð5 mm long. Woody pods, 12 mm long, are
purplish-black when ripe. Flowering occurs from September to October (Brown et al., 1998;
Chandler, 2001).
This species can be distinguished from its close relative, Net-leaved Poison
(Gastrolobium racemosum), by its ovate leaves attached at the narrower end rather than ovate
leaves attached at the broader end (Brown et al., 1998; Chandler, 2001)