Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Manihot walkerae

Manihot davisiae

Texas tapioca, Walker's manihot

Arizona manihot, pata de gallo
Habit Herbs or subshrubs, to 1.5 m. Roots thickened. Herbs or subshrubs, 1–3 m. Roots thickened.
Stems

decumbent to ascending (often growing through associated vegetation), terete when young;

nodes not swollen;

leaf and stipule scars not elevated.

erect, terete when young;

nodes not swollen;

leaf and stipule scars not elevated.
Leaves

stipules lanceolate, entire;

petiole 1–7 cm;

blade peltate, 3–5-lobed, lobes with rounded secondary lobes distal to middle or with 2 pairs of rounded secondary lobes of nearly equal width proximal and distal to middle, median lobe 2–7 cm, margins neither thickened nor revolute, entire, apex cuspidate, surfaces glabrous, abaxial smooth.

stipules lanceolate, entire;

petiole 2–9 cm;

blade basally attached, 5–7-lobed, lobes with rounded secondary lobes distal to middle or with 2 pairs of rounded secondary lobes of nearly equal width proximal and distal to middle, median lobe 4–11 cm, margins neither thickened nor revolute, entire, apex acuminate, surfaces glabrous, abaxial smooth.
Inflorescences

axillary, subspicate racemes, 5–10 cm.

axillary, racemes, to 8 cm.
Pedicels

staminate 1–3 mm;

pistillate 15 mm in fruit, downcurved.

staminate 4–9 mm;

pistillate to 15 mm in fruit, downcurved.
Staminate flowers

calyx tubular, base gibbous, midsection constricted, 10–20 mm, lobes erect or spreading;

stamens 6–8.

calyx campanulate, 7–15 mm, lobes erect or spreading;

stamens 10.
Capsules

1 cm, verrucose-rugose, not winged.

1.5 cm, nearly smooth, not winged.
Seeds

globose, 8–9 mm.

globose, 12 mm.

Manihot walkerae

Manihot davisiae
Phenology Flowering Apr–Sep, following rains. Flowering Jul–Oct.
Habitat Shrublands and grasslands. Desert scrub, thorn scrub, oak woodlands, oak grasslands.
Elevation 20–200 m. (100–700 ft.) 100–2000 m. (300–6600 ft.)
Distribution
from FNA
TX; Mexico (Tamaulipas)
[BONAP county map]
from FNA
AZ; Mexico (Chihuahua, Sinaloa, Sonora)
[BONAP county map]
Discussion

Manihot walkerae is a globally endangered species known from Duval, Hidalgo, and Starr counties and nearby Tamaulipas, Mexico. It is restricted to areas of sandy or gravelly calcareous soils overlying caliche or limestone bedrock. An estimated 95 percent of its habitat in the United States portion of the lower Rio Grande Valley has been converted to largely agricultural uses (www.natureserve.org).

The stamen number (6–8) of Manihot walkerae is notable relative to that of other species in the genus, which typically have 10 stamens per staminate flower.

Manihot walkerae is in the Center for Plant Conservation's National Collection of Endangered Plants.

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

In the flora area, Manihot davisiae is limited to Pima and Santa Cruz counties.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 12, p. 196. FNA vol. 12, p. 194.
Parent taxa Euphorbiaceae > Manihot Euphorbiaceae > Manihot
Sibling taxa
M. angustiloba, M. davisiae, M. esculenta, M. grahamii, M. subspicata
M. angustiloba, M. esculenta, M. grahamii, M. subspicata, M. walkerae
Name authority Croizat: Bull. Torrey Bot. Club 69: 452. (1942) Croizat: J. Arnold Arbor. 23: 224. (1942)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers