Hesperoyucca

(Engelmann) Baker

Bull. Misc. Inform. Kew 1892: 8. 1892.

Common names: Our Lord’s candle Quixote plant
Basionym: Hesperoyucca Engelmann in S. Watson, Botany (Fortieth Parallel), 497. 1871
Treatment appears in FNA Volume 26. Treatment on page 439. Mentioned on page 414, 424, 440.
 TaxonIllustrator 
FNA26 Plate 071.jpegYucca constricta
Hesperoyucca whipplei
Hesperaloe parviflora
Bee F. Gunn
Bee F. Gunn
Bee F. Gunn

Plants simple or cespitose, erect, acaulescent, scapose, rosulate, monocarpic or polycarpic; rosettes solitary or in colonies. Leaf-blades linear, rarely narrowly lanceolate, widest at base, tapering to apex, glaucous, somewhat flexible when young, rigid at maturity, margins pale-yellow, mostly denticulate, corneous, apex distinctly spinose. Scape well developed, extending beyond rosettes, usually more than 2.5 cm in diam., glabrous. Inflorescences paniculate, cylindrical, bracteate, glabrous; rachis and peduncle reddish purple; bracts reflexed, deltate, abruptly narrowing to linear, sharp-pointed apex. Flowers bisexual; perianth campanulate or globose; tepals distinct, white or creamy white to greenish or purple-tinged, broadly lanceolate, 3.2–4.5 (–6) cm; filaments ca. 1.3 cm, equal to or longer than pistil, papillose; anthers reniform; pistil 1–1.3 × 0.6–1 cm; ovary superior; style white, 2–3 mm; stigmas green, capitate. Fruits erect, capsular, obovoid, 3–5 × 1.5–4 cm, dehiscence loculicidal. Seeds many per locule, dull black, thin, flattened, 6–8 mm diam. x = 30.

Distribution

w United States, nw Mexico

Discussion

Species 3 (2 in the flora).

DNA evidence (M. A. Hanson 1993; D. J. Bogler 1994; K. H. Clary 1997) supports W. Trelease’s (1893) recognition of Hesperoyucca at the genus level and reinforces S. D. McKelvey’s (1938–1947, vol. 2) statement that several characteristics of Hesperoyucca whipplei are not typical of Yucca and could justify its removal from Yucca.

J. M. Webber (1953) believed that the differences in leaf, inflorescence, and capsule that McKelvey used to separate Hesperoyucca newberryi from H. whipplei are weak and within the normal ranges of variation in the latter species. F. Hochstätter (2000) treated H. newberryi as a subspecies of H. whipplei. DNA evidence (K. H. Clary 1997) supports specific status for H. newberryi, H. whipplei, and a third species from Mexico, H. peninsularis (McKelvey) Clary. Conclusive DNA analyses have not been performed on the proposed varieties and subspecies of H. whipplei (K. H. Clary 2001), nor has there been any recent systematic morphological work that would support those earlier proposals. For these reasons, only the species of Hesperoyucca are described. This treatment follows S. D. McKelvey’s and K. H. Clary’s interpretations.

Selected References

None.

Key

1 Mature capsules with conspicuous placental wings; plants monocarpic and rosettes single, or plants polycarpic and rosettes cespitose; sw California Hesperoyucca whipplei
1 Mature capsules with slight or inconspicuous placental wings; plants monocarpic, rosettes single; Arizona. Hesperoyucca newberryi

"thick" is not a number. "thin" is not a number."narrowing" is not a number."thin" is not a number.

... more about "Hesperoyucca"
longitudinal +
reniform +
glandular-pubescent +  and glandular +
sharp-pointed +
Karen H. Clary +
(Engelmann) Baker +
Hesperoyucca +
elliptic +, ovate +, oblanceolate +, lanceolate +  and linear +
fibrous +, succulent +  and rigid +
deltate +
Our Lord’s candle +  and Quixote plant +
w United States +  and nw Mexico +
pubescent +  and glabrous +
1.3 cm13 mm <br />0.013 m <br /> (?) +
broadened +
loculicidal +, 1.5cm +  and 4cm +
obovoid +
fleshy +  and dry +
tapering +  and lanceolate +
pseudopetiolate +, sessile +  and simple +
long-lived +  and annual +
dentate +, serrulate +  and entire +
pale-yellow +
denticulate +
cylindrical +, ovoid +  and 3-angled +
not +  and articulate +
reddish purple +
globose +  and campanulate +
semisucculent +
1 cm10 mm <br />0.01 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (?) +  and 1 cm10 mm <br />0.01 m <br /> (?) +
Bull. Misc. Inform. Kew +
reddish purple +
flattened +
exserted +  and included +
aboveground +  and subterranean +
3 +  and 1 +
list +  and count +
exserted +  and included +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Hesperoyucca +
Agavaceae +
4.5 cm45 mm <br />0.045 m <br /> (6 cm60 mm <br />0.06 m <br />) +
creamy white;greenish or purple-tinged +
distinct +
lanceolate +
3.2 cm32 mm <br />0.032 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
scapose +, acaulescent +  and simple +
plant +  and cespitose +
polycarpic +  and monocarpic +
small;gigantic +
petal-like +