Perityle emoryi |
Perityle stansburyi |
|
---|---|---|
Emory's Rock daisy |
Stansbury's Rock daisy |
|
Habit | Annuals (sometimes persisting), 2–60 cm (delicate or robust, stems relatively few to many, erect or spreading); puberulent to hirsute, glandular-pubescent. | Perennials or subshrubs, 7–45 cm (often dense clumps to 60 cm across); hirtellous. |
Leaves | petioles 3–45 mm; blades ovate, cordate, suborbiculate, or triangular, 17–60 × 10–50 mm, margins deeply toothed, lobed, cleft, or divided, lobes indented to irregularly dissected. |
petioles 3–10 mm; blades subdeltate, suborbiculate, or subovate, 3–14 × 3–15 mm, margins usually 2–5-lobed or serrate, sometimes subentire or 3-lobed. |
Peduncles | 1–70 mm. |
5–60 mm. |
Involucres | campanulate to hemispheric. |
campanulate. |
Ray florets | usually 8–14, rarely rudimentary or 0; corollas white, laminae oblong, 1–4(–6) × 1–3 mm. |
6–14; corollas yellow, laminae 3–6 × 1.2–3 mm. |
Disc florets | 40–100+; corollas yellow, tubes 0.7–1.3 mm, throats tubular to tubular-funnelform, 0.8–1.3 mm, lobes 0.1–0.2 mm. |
60–80; corollas yellow, tubes 1.2–1.5 mm, throats tubular to subfunnelform, 2.4–3 mm, lobes 0.4–0.6 mm. |
Phyllaries | 10–20, lanceolate or oblanceolate to ovate-lanceolate, 4–6 × 1–2 mm. |
14–22, lanceolate to broadly oblanceolate, 5–6 × 1–2 mm. |
Heads | borne singly or in corymbiform arrays, 4–10 × 4–10 mm. |
borne singly or in corymbiform arrays, 7–8 × 5–9 mm. |
Cypselae | suboblong, oblanceolate, or subcuneate, (1.5–)2–3 mm, margins thin (not calloused), long- or short-ciliate; pappi 0 or of 1 antrorsely to retrorsely barbellate bristles 1–3 mm plus crowns of hyaline, laciniate scales. |
narrowly oblanceolate, 2–3.5 mm, margins thin-calloused, short-hairy; pappi of single, ± stout bristles 2.5–4 mm plus crowns of vestigial, hyaline scales. |
2n | = 65–72 or 100–116. |
= 34. |
Perityle emoryi |
Perityle stansburyi |
|
Phenology | Flowering year round (depending on latitude). | Flowering spring–fall. |
Habitat | Coastal bluffs, desert plains, slopes, washes | Rock crevices |
Elevation | 10–1500 m (0–4900 ft) | 1200–2600 m (3900–8500 ft) |
Distribution |
AZ; CA; NV; UT; Mexico; South America (Chile, Peru)
|
NV; UT |
Discussion | Perityle emoryi is a widespread polyploid of diverse habitats and is often weedy. It is variable; none of the variation appears to have population significance and does not require taxonomic recognition. The range of P. emoryi appears to be gradually expanding. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Perityle stansburii with its large habit, relatively broad leaves, radiate heads, bristle pappus, chromosome number, and wide distribution, fills most expectations as the ancestral taxon of the group of related species called the “southwestern alliance.” This natural assemblage of taxa, which is thought to have evolved through geographic displacement and subsequent genetic differentiation, includes P. congesta, P. gracilis, P. intricata, P. inyoensis, P. megalocephala, P. specuicola, P. tenella, and P. villosa. These taxa, which are found mostly to the south and west of P. stansburii, all have rayless heads and may or may not have pappus bristles. In western and northwestern Utah and adjacent Nevada, P. stansburii occurs in crevices of rock exposures. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 321. | FNA vol. 21, p. 326. |
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Peritylinae > Perityle > sect. Perityle | Asteraceae > tribe Heliantheae > subtribe Peritylinae > Perityle > sect. Laphamia |
Sibling taxa | ||
Synonyms | Laphamia stansburii | |
Name authority | Torrey: in W. H. Emory, Not. Milit. Reconn., 142. (1848) | (A. Gray) J. F. Macbride: Contr. Gray Herb. 56: 39. (1918) |
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