Morphological and environmental variation within Hibiscus krichauffianus (Malvaceae), and the recognition of two new species, H. verecundus and H. calcareus Author McLay, Todd G. B. Author Barker, Robyn M. Author Albrecht, David E. text Australian Systematic Botany 2023 2023-12-15 36 6 457 477 http://dx.doi.org/10.1071/sb23003 journal article 303636 10.1071/SB23003 45893a38-17f2-4bba-9122-80a3c65ea551 1446-5701 13835582

Table 1. Morphological diagnostic characters delimiting H. krichauffianus sens. strict., and the three new entities.

Character	Morphotype A – Hibiscus krichauffianus	Morphotype B – Hibiscus verecundus	Morphotype C – Hibiscus calcareus	Morphotype D – Hibiscus sp. Belele (D.W.Goodall 3417)
Substrate preference	Deep sand	Typically shallow soils over sandstone, laterite or basalt	Lime-rich soils	Insufficient data
Plant habit	Subshrub or shrub to ~1 m high, usually erect or ascending	Low spreading subshrub or shrub to ~0.5 m high, usually decumbent	Low subshrub to ~0.5 m high, spreading, dome-shaped or rounded	Low or dwarf subshrub or shrub to ~0.3 m high
Branchlet indumentum colour	Silvery-white, white, sometimes fading to yellowish-white	Yellowish-brown, sometimes fading to white	White, or silvery-white	White on younger branchlets, older branchlets becoming ferruginous (ferruginous rays and white rays sometimes on the same hair)
Stipule width (mm)	0.16–0.4	0.1–0.17	0.2–0.5	0.2–0.35
Leaf lamina colour (adaxial)	Whitish-silver to grey, becoming greyish-green with age	Green to dark green	Grey to silvery-white	Silvery–ferruginous
Leaf lamina shape	Mostly ovate to lanceolate or oblong, occasionally broadly ovate	Ovate to broadly ovate, rarely elliptic–ovate	Ovate, elliptic–ovate or oblong–ovate	Ovate to elliptic–ovate
Leaf lamina in transverse	Flat to weakly concave or weakly folded	Flat to weakly concave or weakly folded	Mostly strongly concave to vshaped (and appearing folded on many herbarium specimens)	Flat to weakly folded
Leaf lamina length and width (mm)	10–55 × 5–35	9–52 × 8–33	6–28 × 4–16	17–43 × 6–22
Leaf lamina base	Obtuse, truncate or very broadly cuneate	Broadly cuneate, obtuse or truncate	Broadly cuneate or truncate	Truncate, very slightly cordate or broadly obtuse
Leaf lamina margin	Crenate to dentate	Serrate to dentate, rarely crenate	Serrate to dentate or crenate, undulate, sinus between teeth up to halfway to midvein	Dentate to crenate
Abcision line (at peduncle–pedicel junction), whether visible and position	Not obvious, obscured by hairs, usually 1–2 mm from the base, rarely up to one-half length from the base	Sometimes obvious, one-third to one-half length from the base	±Obvious, sometimes obscured by hairs, usually in upper half, 2–17 (–24) mm from the base	±Obvious, sometimes obscured by hairs, approximately one-third length from the base
Number of epicalyx lobes	5–8 (rarely 10, rarely bifurcating)	5–7	7–8	5–6
Epicalyx length (Including fused portion, excluding receptacle) (mm)	7–16	6–10	4–14	6–12
Fusion of epicalyx lobes at base	Fused for 1–4 mm	Free or fused to 0.5 mm	Fused for 1–3.5 mm	Free or fused for up to 1 mm
Epicalyx lobes degree of curvature	Straight in flower, becoming recurved or rarely incurved in fruit	Straight	Straight in flower, becoming recurved in fruit	Straight in flower, becoming recurved in fruit
Corolla colour	Pale pink or mauve (rarely white)	Pale pink or white (sometimes drying pale yellow)	Pale pink to mauve, sometimes almost white	Purple
Petal length (mm)	17–35	15–28	20–44	39–42
Seed indumentum	Patchy indumentum of wispy spreading, white to off-white hairs	Short patchy indumentum of appressed white to yellowish-brown hairs	Short patchy indumentum of appressed white hairs	Short patchy indumentum of appressed white to yellowish hairs
Seed length (mm, greatest dimension)	2–3	1.7–2.3	2.5–3	~3
Seed characteristic features or notes	Reniform (rarely subangular–reniform), funicular remnants brown, membranous and wing-like, on either side of the hilum	Two straighter sides almost forming a right angle at intersection, funicular remnants brown, membranous and wing-like, one centrally placed and one on either side of the hilum	Two straighter sides almost forming a right angle at intersection, funicular remnants brown, membranous and wing-like, on either side of the hilum	Two straighter sides almost forming a right angle at intersection, funicular remnants brown, membranous and wing-like, on either side of the hilum
Flower cleistogamy	Observed in some specimens	No evidence	Observed in a single specimen	Not observed in material examined