Philadelphus mearnsii

W. H. Evans ex Rydberg in N. L. Britton et al.

N. Amer. Fl. 22: 174. 1905.

Common names: Mearns’s mock orange
Synonyms: Philadelphus hitchcockianus S. Y. Hu P. mearnsii subsp. bifidus C. L. Hitchcock
Treatment appears in FNA Volume 12. Treatment on page 478. Mentioned on page 474, 475, 476.

Shrubs, 5–15 (–40) dm. Stems tan-brown, weathering gray, striate, stiffly divaricately branched, strigose-sericeous; internodes 0.1–3.5 cm; short-shoots often present; axillary buds exposed. Leaves: petiole 0.5–4 mm; blade green or gray-green abaxially and adaxially, oblong-lanceolate, linear-lanceolate, or elliptic to ovate, 0.5–1.7 (–3) × 0.1–0.6 (–1.1) cm, coriaceous, margins entire, ± revolute, surfaces ± equally moderately strigose, hairs appressed, coarse, 0.2–0.6 (–0.9) mm, without understory of coiled-crisped hairs; veins inconspicuous. Inflorescences: flowers solitary, produced from previous years long-shoots, often appearing axillary. Pedicels 0.5–2 mm. Flowers: hypanthium sparsely to moderately strigose-sericeous or glabrous; sepals ovatelanceolate, 2–3.5 (–4.2) × 1.3–2.3 mm, apex acute to acuminate-caudate, abaxial surface sparsely to moderately strigose-sericeous or glabrous, adaxial surface glabrous except villous along distal margins; petals white, oblong-lanceolate to broadly oblong-ovate, (5–) 7–8.5 (–10) × 2.5–4.5 (–5.8) mm; stamens 13–18 (–24); filaments distinct, 1.3–4 mm; style 1, clavate, 2–3.2 mm, narrow base 0.5–1.5 mm; stigmatic portion 1.3–2 mm, distally lobed to 0.5 mm. Capsules ovoid-turbinate, 3–5.5 × 3.2–5.5 mm, sepals ± persistent at distal 1/3 or more distally, capsule distal surface impressed in 4 (–8) radial lines. Seeds not caudate, 1–1.2 mm.


Phenology: Flowering Apr–Jun; fruiting May–Nov.
Habitat: Limestone mountains, oak-pinyon zones.
Elevation: 1300–1800(–2200) m.

Distribution

V12 524-distribution-map.jpg

N.Mex., Tex., Mexico (Coahuila)

Discussion

Philadelphus hitchcockianus, with its hypanthium and abaxial sepal surfaces glabrous, is here synonymized with P. mearnsii, which has its hypanthium and abaxial sepal surfaces moderately sericeous-strigose; substantial variation in this character is found in several populations. Hu S. Y. (1954–1956) alleged that P. hitchcockianus and P. mearnsii also differ in fruit size; however, that character is variable and overlapping.

Selected References

None.

Lower Taxa

None.

"connate" is not a number. "distinct" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Philadelphus mearnsii"
glabrous +  and strigose-sericeous +
distinct +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
perigynous +  and epigynous +
oblong;depressed-ovate +
acute +  and acuminate-caudate +
Alan S. Weakley +  and James Henrickson +
W. H. Evans ex Rydberg in N. L. Britton et al. +
exfoliating +
clawed +  and tapered +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
1.7 cm17 mm <br />0.017 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
gray-green +  and green +
0.5 cm5 mm <br />0.005 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
elliptic +  and ovate +
coriaceous +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
arching;spreading;ascending;spreading;ascending;erect +
0.3 cm3 mm <br />0.003 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
ovoid-turbinate +
coriaceous +
0.32 cm3.2 mm <br />0.0032 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
Mearns’s mock orange +
N.Mex. +, Tex. +  and Mexico (Coahuila) +
1300–1800(–2200) m. +
1-49-flowered +
loculicidal +  and septicidal +
intercostal +  and interstylar +
Limestone mountains, oak-pinyon zones. +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
coiled-crisped +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
8-ribbed +  and 4-ribbed +
glabrous +  and strigose-sericeous +
hemispheric +, obconic +  and turbinate +
axillary +  and terminal +
0.1 cm1 mm <br />0.001 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
drought-deciduous +
revolute +  and plane +
0 +  and 1/2 +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
perigynous +  and epigynous +
0.85 cm8.5 mm <br />0.0085 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.58 cm5.8 mm <br />0.0058 m <br />) +
7mm;8.5mm +
spreading +  and ascending +
oblong-lanceolate +  and broadly oblong-ovate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Flowering Apr–Jun +  and fruiting May–Nov. +
N. Amer. Fl. +
rusty brown +
1 +  and 50 +
not caudate +
0.1 cm1 mm <br />0.001 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.42 cm4.2 mm <br />0.0042 m <br />) +
persistent +
connate +  and distinct +
reflexed +  and spreading +
glabrous +, strigose +  and villous +
ovatelanceolate +
enlarged +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
reddish-brown +, brown +  and grayish +
free +, connate +  and distinct +
gray +  and tan-brown +
weathering +
spreading;arching;spreading;arching;ascending;erect +
strigose-sericeous +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +
clavate +
0.2 cm2 mm <br />0.002 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
Philadelphus hitchcockianus +  and P. mearnsii subsp. bifidus +
Philadelphus mearnsii +
Philadelphus +
species +
with simple trichomes +  and glabrous +
inconspicuous +
deciduous +  and evergreen +