Nelsonia

Scientific name

Nelsonia R. Br.

Common names

blue pussyleaf

Family

Acanthaceae

Similar genera

Hemigraphis, Hygrophila, Staurogyne

Native distribution

Old World tropics

Species cultivated

Nelsonia campestris R.Br. [synonym of Nelsonia canescens (Lam.) Spreng.]

Adventive distribution

It has not been determined if Nelsonia canescens is introduced into or native to the New World.

Weed status

not weedy

Habit

creeping, sprawling, prostrateprostrate:
(adj) growing closely along the ground
, or decumbentdecumbent:
(adj) (of stems) having a portion lying along the ground, with upper parts erect or ascending
herb

Brief description

Small creeping herb. Stem rooting at nodes, emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
vegetation pubescentpubescent:
(adj) (1) covered with short, soft hairs; (2) bearing hairs
. Leaves oppositeopposite:
(adj) (of leaves) two leaves per node; in pairs on opposite sides of an axis
; shortly petiolatepetiolate:
(adj) relating to or in the form of a petiole; bearing petioles
; bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
elliptic to ovateovate:
(adj) egg-shaped in outline; generally with the broad end at or near the base
; apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
acuteacute:
(adj) tapering to a sharp, pointed apex with more or less straight sides; broader than acuminate; forming an angle of less than 90 degrees
; base round to attenuateattenuate:
(adj) narrowing gradually to a point
; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
; venationvenation:
(n) the arrangement of veins in a leaf
pinnatepinnate:
(adj) in the form of a feather; of, e.g., leaflets, lobes, or veins: arranged in two rows along an axis
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
a terminalterminal:
(adj) at the apex
spikespike:
(n) an indeterminate, unbranching inflorescence of sessile flowers or flower clusters on a usually elongated axis
subtended by overlapping bracts. Flowers zygomorphiczygomorphic:
(adj) bilaterally symmetrical; symmetrical along only one plane
, ± spirally arranged; sessilesessile:
(adj) attached directly, without a stalk
. Calyxcalyx:
(n) the outer whorl of the perianth; all the sepals of a flower
4-lobed to base; corollacorolla:
(n) the inner whorl(s) of the perianth; all the petals of a flower
tube 2-lipped, lower 3-lobed, upper 2-lobed; white to pink or bluish purple; stamens 2; stigmastigma:
(n) the portion of the pistil that is receptive to pollen
2-lobed, unequal.

Natural habitat

moist forest regions, savannah woodlands, grassy places, floodplains, riverbanks, and open and disturbed habitats, especially in moist areas along roadsides, trails, and streambeds

Additional comments

Nelsonia contains three species. It is suggested that only a single species, N. canescens, should be recognized.

  Nelsonia   campestris , emersed; photo: S.L. Winterton

Nelsonia campestris, emersed; photo: S.L. Winterton

  Nelsonia   campestris  flower; photo: S.L. Winterton

Nelsonia campestris flower; photo: S.L. Winterton