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gray amsonia, woolly bluestar

tubular bluestar

Stems

erect, 11–65 cm, glabrous or tomentose;

branches usually borne on most of stem (occasionally confined to distal portion), well exceeding infructescence.

erect, 16–60 cm, glabrous or sparsely to moderately pubescent;

branches often borne on most of stem (or only distal portion), often remaining shorter than infructescence.

Leaves

petiole 1–5 mm, glabrous or tomentose (leaves rarely sessile);

leaf blades slightly or moderately heteromorphic;

stem leaf blades ovate to narrowly lanceolate, narrowly to very narrowly elliptic, or elliptic, (2–)3–5(–6) cm × (3–)4–27 mm, margins entire, not revolute, not ciliate, apex acute (somewhat acuminate), surfaces glabrous or densely (rarely sparsely) tomentose;

branch leaf blades narrower than stem leaf blades, (2.2–)3–4.7(–5.6) cm × (2–)3–6(–13) mm.

petiole 0–2.5 mm, glabrous or sparsely to moderately pubescent;

blades slightly heteromorphic;

stem leaf blades linear to ligulate (very narrowly elliptic or lanceolate), (2.3–)3–6.5(–9) cm × (0.7–)1–2.8(–5) mm, margins entire, sometimes somewhat revolute, ciliate or not, apex narrowly acute, surfaces glabrous or sparsely to moderately pubescent;

branch leaf blades linear, (1.1–)2.5–5.2(–7) cm × 0.5–1.3(–3) mm.

Flowers

sepals subulate or narrowly deltate (deltate), (2–)3.5–6(–7.5) mm;

corolla tube green to purplish or pinkish green, (7–)8–12(–13) mm, lobes bluish (violet- to lavender-tinged) to white especially after anthesis (pinkish, bluish, or purple-tinged), (2.8–)4.5–8 mm, outer surface of corolla glabrous.

sepals narrowly deltate (to subulate) with weak, often curved apex, (2–)3.5–7(–9.5) mm;

corolla tube bluish to lead-colored, lavender or purplish below, often greenish above, (20–)28–41(–45) mm, lobes white to cream or bluish white (pale pink), (6.5–)9–13.5(–18) mm, outer surface of corolla glabrous.

Seeds

(8–)11–17 × (3–)3.9–5.5(–6.3) mm.

5.3–8.1(–10.5) × 1.5–2.7 mm.

Follicles

erect (aberrantly deformed and spreading), 2–8(–9.5) cm × (4–)4.8–6.8 mm, apex acuminate, glabrous (partly tomentose).

erect, (3.8–)6–11(–20) cm × (2.4–)2.9–4 mm, apex short-acuminate (acute), glabrous.

Amsonia tomentosa

Amsonia longiflora

Distribution
map from USDA
sw United States
[WildflowerSearch map]
[BONAP county map]
map from USDA
sc United States; n Mexico
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Both varieties of Amsonia tomentosa have an unusual pattern of variation in pubescence. Stems and leaves are usually either densely tomentose or glabrous, with intermediate density of pubescence rare. In some populations, the two forms are found together, suggesting that indument may be a single-gene trait.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 2 (2 in the flora).

The varieties of Amsonia longiflora are distinguished by differing pubescence. Both are generally found on limestone substrates. Notes on a specimen collected by R. C. Sivinski (Sivinski 4282, UNM) indicate that var. longiflora was collected on dolomite and had pale blue corollas, whereas nearby var. salpignantha occurred on gypsum and had white to pale pink corollas (the latter is rarely reported, and corolla lobe color is not consistently different between the two varieties). It is not known whether this substrate preference may be consistent and contributes to maintaining the distinction between the two. Both are restricted to southern New Mexico and Texas, but var. longiflora is confined to a relatively small portion of western Texas, while var. salpignantha is more widely distributed in western Texas, and occurs also in several counties in a disjunct portion of central Texas.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Parent taxa Apocynaceae > Amsonia > subg. Articularia Apocynaceae > Amsonia > subg. Sphinctosiphon
Sibling taxa
A. arenaria, A. ciliata, A. fugatei, A. grandiflora, A. hubrichtii, A. jonesii, A. kearneyana, A. longiflora, A. ludoviciana, A. palmeri, A. peeblesii, A. rigida, A. tabernaemontana, A. tharpii
A. arenaria, A. ciliata, A. fugatei, A. grandiflora, A. hubrichtii, A. jonesii, A. kearneyana, A. ludoviciana, A. palmeri, A. peeblesii, A. rigida, A. tabernaemontana, A. tharpii, A. tomentosa
Subordinate taxa
A. tomentosa var. stenophylla, A. tomentosa var. tomentosa
A. longiflora var. longiflora, A. longiflora var. salpignantha
Key
1. Stem leaf blades ovate to lanceolate (narrowly elliptic to elliptic), (6–)8–27 mm wide, branch leaf blades markedly narrower, 4–13 mm wide; w, s Arizona, California, Nevada.
var. tomentosa
1. Stem leaf blades narrowly to very narrowly elliptic or narrowly lanceolate, (3–)4–8(–10) mm wide, branch leaf blades slightly narrower, (2–)3–6(–7) mm wide; n Arizona, Utah.
var. stenophylla
1. Stems, leaves, petioles, and outer surface of calyces glabrous; leaf margins not ciliate, not revolute.
var. longiflora
1. Stems, leaves, petioles, and outer surface of calyces usually sparsely to moderately pubescent (seldom glabrate to glabrous); leaf margins at least sparsely ciliate, occasionally somewhat revolute.
var. salpignantha
Name authority Torrey & Frémont in J. Frémont: Rep. Exped. Rocky Mts., 316. (1845) Torrey in W. H. Emory: Rep. U.S. Mex. Bound. 2(1): 159. (1859)
Source FNA vol. 14. Treatment authors: Linh Tõ Ngô, Wendy L. Applequist. FNA vol. 14. Treatment authors: Linh Tõ Ngô, Wendy L. Applequist.
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