cardunculus showed the presence of triterpenoid saponins in the involucral
bracts of this plant (Mucaji et al.
bract shape and width are diagnostic for the parental species (Heiser 1947) and are inherited additively in hybrids (LHR, pers.
About the time resin secretion by floral bractlets became associated with reward rather than defense functions, the involucral
bracts evolved larger size and often bright colors, apparently as a floral advertisement to pollinators [ILLUSTRATION FOR FIGURE 3 OMITTED].
bract and bracteoles of the staminate flower have a single-layered epidermis on both surfaces (see Figure 2A, B).
bracts linear-lanceolate, acute, [+ or -] 1 mm wide; with stellate, glandular and long simple eglandular trichomes in more or less similar proportions (generally, the eglandular trichomes are the most abundant).
30-55 cm long), involucral
bracts and primary bracts green or sometimes reddish at their distal portion (vs.
Euphorbia spellenbergiana is a delicate completely prostrate annual, with entire, oblong to suborbicular, or ovate leaves, reduced subequal or nonexistant involucral
gland appendages, smooth (non-ridged) seeds, and puberulent stems.
5 mm de largo, glabras o pilosas, receptaculo conico, paleas exteriores ovadas, ciliadas, ubicadas por pares y rodeando en conjunto con una bractea involucral
al aquenio contiguo, las interiores lanceoladas, enteras a someramente trifidas; flores liguladas 5, sus tubos de 1 a 1.
Nature of proximal involucral
bract: 0, stipuliform; 1, involucral
15 mm in diameter, white, glabrous; scape bracts obovate, distinctly concave and inflated toward the apex, apex rounded to obtuse and apiculate, erect, entire, whitish-hyaline in the basal 3/5, red in the apical 2/5, inconspicuously and sparsely white-lepidote inside, glabrous outside, membranous, the upper ones somewhat involucral
, 35-45 x 25 mm, about equaling 2/5 of the sepals length.
Within the inflorescence, branches are usually subtended by primary or involucral
bracts (Goetghebeur, 1986).
It differs from most Mexican Scirpeae in having well developed leaves and foliaceous involucral
bracts, characters shared with Bolboschoenus and Scirpus sensu stricto.