The Lemon-yellow rosemallow is in Family Malvaceae.
They are a perennial herb up to 1 or 1.5 m high with green stems.
Younger stems have hairs that are lost on older plants.
They may become a rounded shrub over 2 m high with woody stems.
There are multiple branching stems and woody stems have fissured bark.
Leaves are opposite and decussate (in 4 ranks).
Petioles, up to 5 or 10 cm long are covered in stellate hairs when young.
Stipules, at the base of the petiole are up to 1.5 cm long and a mm or two wide.
They may have a few short hairs.
The almost round to ovate blades may have 3 or 5 slight to obvious lobes.
From 5 to around 15 cm wide the blades have a pointed tip and serrated edge.
Leaves have simple and stellate hairs mainly when young and on the lower surface.
Older leaves usually still have some on the lower surface and there maybe a few on the midvein on the upper.
Blades are paler on the lower surface.
Inflorescences are scattered solitary axillary flowers.
They are on a hairy pedicel/peduncle up to 2 cm long.
Under the flower are 5 bracts that are partly fused into an epicalyx.
Up to 2.5 or 3 cm long they are joined for a few mms at the base.
They widen towards the middle then narrow towards the end.
Growing past the tip of the blade the midvein forms a narrow bristle-like extension around 5 mm long.
There are stellate hairs on the outer surface of the blade.
The calyx has 5 green sepals around 1.5 to 2 cm long and under 1 cm wide.
The bases are fused for around half that length with roughly ovate lobes on the rim.
Sepals have a prominent midrib (nerve, vein) and often a smaller one each side.
There are hairs on the outer surface especially on the midrib.
The 5 petals have a narrow base and a roughly circular lobe.
The overlapping lobes, up to 6 cm long have a few small hairs on the outer surface.
They are a bright to lemon-yellow with a dark red-brown base.
The stamen filaments are fused into a tube with 5 triangular lobes at the top.
Down the sides of the tube are the anthers on the short free filament ends.
The superior ovary has 5 locules with ovules in vertical rows.
The single style divides into 5 short branches at the top of the staminal tube.
Each branch has a spherical deep purple stigma with short hairs.
Fruit are a thin papery loculicidal capsule up to around 2.5 cm long.
The old epicalyx and calyx lobes are still attached.
Each of the 5 chambers has numerous dark seeds.
J.F.
