Richardsonii:  Answers to key questions in Budd's Flora and Flora of Alberta leading to this species.   leaves both basal and alternate-cauline; NOT [leaves all basal] leaves 3-7-divided into linear segments; NOT [leaves entire] heads 1-3(5) , in flat-topped corymbs; NOT [heads solitary on unbranched stalks] involucral bracts dissimilar, in 2 definite series, the outer ones partly united; NOT [involucral bracts similar, in 2 or 3 indefinite series, none united]

 

Hymenoxys: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus.  The answers do not apply to all species of Hymenoxys found on the Canadian prairies, but they do apply to H. richardsonii. NOT [plants with woody caudex, leaves linear, involucre glandular-glutinous] plants of dry habitats; NOT [plants of moist habitats] juice watery; NOT milky stem 1-2 dm tall; NOT [stem usually much taller] plants with leafy stems; NOT [plants more or less scapose, cauline leaves none, or few and reduced to bracts] (This applies to H. richardsonii, but not to H. acaulis.) all leaves alternate; NOT [lower leaves opposite] leaves usually pinnatifid with narrow lobes; NOT [leaves lanceolate] flower heads more than 6 mm across heads usually less than 35 mm across; NOT [heads large, usually more than 35 mm across] involucre NOT sticky and gummy involucral bracts of 2 distinct, dissimilar series; NOT [involucral bracts in one or more series, all more or less the same] involucral bracts NOT reflexed; NOT [involucral bracts decidedly reflexed or turned backward when mature] receptacle bare and naked, without chaffy scales but sometimes bristly; NOT [receptacle with chaffy scales between florets] flower heads with both tubular and ray florets (radiate heads) all florets yellow; NOT [disk florets purple, ray florets yellow with usually a purplish base] ray florets yellow; NOT [ray florets white, to pink, purple or blue]; stamens united to form a tube around the pistil pappus, when present, composed of scales or bristles; NOT [pappus composed of hairs] length of seeds less than four times the width; NOT [seeds long, the length four times the width]