Leafl. Bot. Observ. Crit. 1: 206. 1906.
Subshrubs or perennial herbs, often woody at base, glabrate to densely pubescent, hairs variously stellate to simple. Stems solitary to many, erect or ascending, rarely decumbent. distinct. Flowers: calyx somewhat accrescent or not, not inflated, lobes not strongly ribbed, lanceolate to ovate or ovate-triangular; corolla campanulate to subrotate, whitish or pinkish to rose-purple, exceeding calyx; staminal column ± included; filaments terminal and subterminal; ovary (6–) 10–15 (or 16) -carpellate; ovules 2 or 3 (or 4) per carpel; styles (6–) 10–15 (or 16) -branched, (branches equal in number to carpels); stigmas terminal, obliquely capitate. Fruits schizocarps, erect, not inflated, subglobose, apically retuse, moderately indurate; mericarps (6–) 10–15 (or 16), drying black, 1-celled, oblong in lateral view, rounded at apex, thin-walled, smooth laterally, without dorsal spur, densely pubescent dorsally and apically with coarse, hirsute, velutinous simple hairs overlaying stellate hairs, sides smooth, glabrous, dehiscence loculicidal except ventral-basally where joined to columella by vascular-bundles. Seeds 2 or 3 (or 4) per mericarp, reniform to obovate-reniform, glabrate or puberulent marginally with simple, white to tawny hairs 1–2 mm. x = 33.
Iliamna comprises one widespread species of the mountainous West (I. rivularis), and seven local species (two eastern and five western) differing principally but modestly in pubescence, leaf, involucellar bractlet, and calyx characters, and exhibiting varying degrees of intergradation. All, with the exception of I. bakeri, are species of relatively mesic, open woodlands, scrub, and meadows, often along stream banks. Each of the species apparently regenerates following disturbance or fire, sometimes in dense stands.
Species 8 (8 in the flora).
|1||Involucellar bractlets 8–14 × 2–6 mm, 3/4 to exceeding calyx length||> 2|
|1||Involucellar bractlets 3–10 × 1 mm, 1/3–2/3 calyx length||> 3|
|2||Involucellar bractlets lanceolate-ovate, 8–12 × 2–3 mm, 3/4 calyx length.||Iliamna grandiflora|
|2||Involucellar bractlets elliptic-lanceolate to -ovate, 10–14 × 4–6 mm, equaling or exceeding calyx length.||Iliamna latibracteata|
|3||Calyces at anthesis 5–8(–11) mm; involucellar bractlets 3–6(–8) mm.||Iliamna rivularis|
|3||Calyces 9–20 mm; involucellar bractlets (5–)6–10 mm||> 4|
|4||Calyx lobes ovate to triangular-ovate, ± as wide as long, ± equaling tube in length||> 5|
|4||Calyx lobes lanceolate to narrowly ovate, longer than wide, exceeding tube in length||> 6|
|5||Leaf blades 6–20 cm wide, (3-)5- or 7-lobed, terminal lobe triangular-ovate, sinuses broad.||Iliamna remota|
|5||Leaf blades 1.5–8 cm wide, shallowly and crenately 3-lobed or deeply 3- or 5-lobed, terminal lobe narrowly oblong, sinuses narrow.||Iliamna bakeri|
|6||Calyx 9–12 mm; involucellar bractlets 6–8 mm.||Iliamna corei|
|6||Calyx 15–20 mm; involucellar bractlets 5–10 mm||> 7|
|7||Calyces and stems pubescent with simple and stellate hairs; petals deep rose-purple; plants 1–2 m.||Iliamna longisepala|
|7||Calyces and stems obscurely pubescent with fine stellate hairs; petals whitish or pinkish; plants 0.5–0.7 m.||Iliamna crandallii|