NT Flora

Juncus acutus L. subsp. acutus
JUNCACEAE
Synonymy

Common Name: Juncus, Sharp Rush, Spiny Rush

Description: Juncus acutus subsp. acutus most closely resembles the native species J. kraussii, both differing from other Juncus spp. in the bioregion by the well developed cylindical pungent-tipped leaves that closely resemble the flowering stems and the absence of 2 bracteoles at the base of the perianth. Juncus acutus subsp. acutus is readily distinguished from J. kraussii by the larger capsules (4-6 mm long, cg. 2.2-3 mm long) that far exceed the perianth segments, and longer dull seeds (1.3-2 mm long, cf. 0.5-1 mm long). Juncus acutus subsp. acutus also tends to have slightly broader leaf blades that are more variably coloured and often bluish-green (cf. consistently green).

Diagnostic Characters: Juncus species can be distinguished from other monocotyledons in the bioregion by a combination of the following features: leaves non-succulent and with sheaths not fused into a tube, perianth segments 6 in number and green (occasionally red-brown tinged and quickly turning straw-coloured), and fruits capsular with numerous tiny seeds.