Pleradenophora bilocularis

(S. Watson) Esser & A. L. Melo

Phytotaxa 81: 34. 2013.

Common names: Arrow poison plant hierba de la fleche
Illustrated
Basionym: Sebastiania bilocularis S. Watson Proc. Amer. Acad. Arts 20: 374. 1885
Synonyms: Sapium biloculare (S. Watson) Pax S. biloculare var. amplum I. M. Johnston
Treatment appears in FNA Volume 12. Treatment on page 233.
Revision as of 17:31, 29 July 2020 by imported>Volume Importer
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Shrubs or small trees, 1–8 m. Leaves distichous, clustered at branch tips; stipules triangular, 0.8–1 × 1.5–2.5 mm, erose, hyaline; petiole 1.2–4 mm, glands 0–2, orbicular, axil with tuft of coarse glandular-hairs; blade lanceolate, 2–7 × 0.5–1.8 [–3] cm, base acute, margins with fine teeth bearing setae, teeth sometimes replaced by orbicular glands, apex acute. Inflorescences: peduncle 0.2–0.6 cm; fertile portion 3–6 cm; staminate cymules numerous, condensed, each with 3–10 flowers per bract; pistillate flowers 0–4 per inflorescence, 1 flower per bract; bracts ovate, 1.5–2 mm, subtended on each side by row or cluster of 5–7 elliptic glands, 0.1–0.3 mm diam. Pedicels 0–2 mm. Staminate flowers yellowish green; sepals 0.5 mm; filaments 0.3–0.8 mm, anthers 0.2–0.3 mm. Pistillate flowers yellowish green; sepals ovate, 1–2 mm; styles 2.5–3.5 mm, connate 1/3 length, free portion coiled. Capsules subglobose, 0.5–-1 cm diam. Seeds 4–5 mm, wider than long; seed-coat silver and brown mottled, smooth with verrucose patches. 2n = 22.


Phenology: Flowering and fruiting year-round.
Habitat: Sonoran desert scrub, thorn scrub.
Elevation: 0–1000 m.

Distribution

Ariz., Mexico (Baja California Sur), Mexico (Sonora)

Discussion

Pleradenophora bilocularis reaches its northern limit of distribution in southwestern Arizona and is widespread in adjacent Sonora, Mexico. Across its range, there is a six-fold variation in leaf width with collections from Baja California being much wider (to 3 cm) and formerly recognized as a distinct variety (V. W. Steinmann and R. S. Felger 1997). The species is a minor source for “Mexican jumping beans” from seeds parasitized by moth larvae. Indigenous populations used the latex as arrow and fish poison (C. E. Bradley 1956).

Selected References

None.

Lower Taxa

None.

"wider than long" is not a number."connate" is not a number. "distinct" is not a number."/3" is not declared as a valid unit of measurement for this property."fine" is not a number.

0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (?) +  and 0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +
Kenneth J. Wurdack +
(S. Watson) Esser & A. L. Melo +
Sebastiania bilocularis +
1.8 cm18 mm <br />0.018 m <br /> (3 cm30 mm <br />0.03 m <br />) +
2 cm20 mm <br />0.02 m <br /> (7 cm70 mm <br />0.07 m <br />) +
lanceolate +
0.5 cm5 mm <br />0.005 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
10 +  and 14 +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
subglobose +
Arrow poison plant +  and hierba de la fleche +
condensed +  and staminate +
Ariz. +, Mexico (Baja California Sur) +  and Mexico (Sonora) +
0–1000 m. +
pistillate +  and staminate +
yellowish green +
subtending +
0 +  and 2 +
orbicular +
Sonoran desert scrub, thorn scrub. +
leaf-opposed +, terminal +  and axillary +
semipersistent +
palmate +  and pinnate +
crenate +, repand +  and subentire +
verrucose +
0 cm0 mm <br />0 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
connate;distinct +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Flowering and fruiting year-round. +
2[-3]-carpellate +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
silver and brown mottled +
ovoid-oblong +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
distinct +  and connate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Illustrated +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
triangular +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
multifid +  and 2-fid +
0.25 cm2.5 mm <br />0.0025 m <br /> (?) +  and 0.35 cm3.5 mm <br />0.0035 m <br /> (?) +
Sapium biloculare +  and S. biloculare var. amplum +
Pleradenophora bilocularis +
Pleradenophora +
species +
racemelike +
evergreen +, deciduous +, perennial +, biennial +  and annual +
tree +  and shrub +