Publ. Bussey Inst. Harvard Univ. 1979: 20, plates 3, 4. 1979.

Common names: Spectacle-pod
Etymology: Latin dimorphus, having two forms, and carpus, fruit, alluding to production of two fruit types in some species
Treatment appears in FNA Volume 7. Treatment on page 604. Mentioned on page 237, 240.

Annuals, biennials, or, rarely, perennials; not scapose; densely pubescent throughout, trichomes usually subsessile and stellate, mixed with minutely stalked, dendritic ones, rarely unbranched. Stems erect [ascending], unbranched or branched proximally, branched distally. Leaves basal and cauline; petiolate or sessile; basal not rosulate, petiolate, blade margins dentate, pinnatifid, or lobed; cauline sessile, subsessile, or shortly petiolate, blade (base not auriculate), margins entire or lobed. Racemes (corymbose), considerably elongated in fruit. Fruiting pedicels divaricate, sometimes ascending or slightly reflexed, slender. Flowers: sepals widely spreading to reflexed, oblong, (equal), lateral pair not saccate basally; petals (spreading), white or lavender, obovate (longer than sepals), claw well-differentiated from blade, (apex rounded); stamens (somewhat spreading), tetradynamous; filaments not dilated basally; anthers oblong [sagittate]; nectar glands distinct, lateral and median present; (gynophore to 0.5 mm). Fruits silicles, subsessile, breaking into two 1-seeded units at maturity, didymous, suborbicular, or broader than long, winged, strongly angustiseptate; valves keeled, enclosing seeds when falling off, not winged, narrowly winged, or margined, indurated around margin, glabrous or pubescent; replum concealed by valve margin; septum complete (ca. 0.1 mm wide); ovules 2 per ovary; style relatively short or obsolete, (terete or flattened); stigma conical, decurrently 2-lobed (appearing entire). Seeds aseriate, strongly flattened, not winged, broadly oblong to suborbicular; seed coat (smooth), not mucilaginous when wetted; cotyledons accumbent to obliquely incumbent. x = 9.


sw United States, n Mexico.


Species 4 (3 in the flora).

Dimorphocarpa membranacea (Payson) Rollins is known from northern Mexico (San Luis Potosí, Tamaulipas).


1 Fruit valves (7-)8-10 mm; petals (7-)8-10(-12) mm, claws not expanded basally; distal cauline leaves sessile, blades usually ovate to narrowly oblong, rarely lanceolate, bases obtuse to truncate. Dimorphocarpa candicans
1 Fruit valves 4-5.5(-6.5) mm; petals (3.5-)4-7(-8) mm, claws expanded basally; distal cauline leaves shortly petiolate or subsessile, blades linear to lanceolate, bases cuneate > 2
2 Distal cauline blades: margins pinnately lobed; fruit valves nearly as long as wide, rounded apically. Dimorphocarpa pinnatifida
2 Distal cauline blades: margins usually entire, rarely dentate; fruit valves often longer than wide, truncate apically. Dimorphocarpa wislizeni
... more about "Dimorphocarpa"
Ihsan A. Al-Shehbaz +
Rollins +
Spectacle-pod +
sw United States +  and n Mexico. +
Latin dimorphus, having two forms, and carpus, fruit, alluding to production of two fruit types in some species +
Publ. Bussey Inst. Harvard Univ. +
rollins1958a +  and rollins1979c +
Cruciferae +
Dimorphocarpa +
Brassicaceae tribe Physarieae +