Trans. Amer. Philos. Soc., n. s.7: 337. 1840
c United States, n Mexico.
Species 3 (3 in the flora).
See discussion of Filagininae following the tribal description (p. 385).
Diaperia occurs in open, moist or dry habitats of humid to semiarid, temperate to subtropical climates. Though apparently not aggressively invasive in their native range, the species are competitive in disturbed habitats (vacant lots, fallow fields, lawns, cemeteries, and roadsides). Diaperia verna var. verna, in particular, is widely regarded as a weed; the species are potentially invasive outside the flora.
Diaperia appears to be monophyletic, with ancestors near Evax sect. Filaginoides Smoljaninova of the Mediterranean basin and central Asia (particularly E. eriosphaera Boissier & Heldreich; J. D. Morefield 1992). It is separated from Evax by stems well-developed, leafy, usually branched, paleae falling together (coherent distally by tangled indument), and staminate paleae somewhat enlarged, apices obtuse, ± herbaceous, uniformly hairy (Morefield 2004). Species of Diaperia are sharply distinct by size, shape, and arrangement of branches, glomerules, heads, and capitular leaves.
Diaperia candida is aberrant by its inner florets bisexual, bisexual paleae distally gibbous, and reported chromosome complement of 2n = 14 (D. J. Keil and D. J. Pinkava 1976). These traits might eventually justify resurrection of the monotypic Calymmandra Torrey & A. Gray, after further study and confirmation of the chromosome number. While 2n = 14 is common elsewhere in Gnaphalieae, all other 25 counted species of Filagininae have 2n = 28 (species of Evax, Filago, Logfia, Micropus, Psilocarphus, and Stylocline) or 2n = 26 (Diaperia and Evax). The implication that D. candida retains an ancestral diploid condition has no phylogenetic support (J. D. Morefield 1992).
|1||Heads in racemiform or spiciform arrays, 1.5–2 mm; branches proximal or none; longest pistillate paleae 0.9–1.3 mm; bisexual florets 3–5 (corollas 0.5–0.9 mm, protruding from heads); functionally staminate florets usually 0||Diaperia candida|
|1||Heads in ± dichasiform or pseudo-polytomous arrays, 2–4.5 mm; branches proximal and distal, rarely none; longest pistillate paleae 1.9–4 mm; bisexual florets 0; functionally staminate florets 2–5 (corollas 1.4–2.5 mm, hidden in heads)||> 2|
|2||Heads in subdichasiform arrays, ± campanulate to spheric, 2–3.3 mm, heights ± equal to diams.; capitular leaves ± hidden between and surpassed by heads; pistillate paleae scarcely imbricate; cypselae mostly 0.7–0.9 mm||Diaperia verna|
|2||Heads in strictly dichasiform or pseudo-polytomous arrays (sometimes appearing monochasiform), ellipsoid to ± cylindric, 3.5–4.5 mm, heights 2–3 times diams.; capitular leaves visible between and surpassing heads; pistillate paleae imbricate; cypselae mostly 0.9–1.2 mm||Diaperia prolifera|
|Author||James D. Morefield +|
|Common name||Rabbit-tobacco + and dwarf cudweed +|
|Etymology||Greek diapero, to pass through, alluding to pseudo-polytomous branching pattern (“proliferous inflorescence”) of type species +|
|Illustrator||Linny Heagy +|
|Synonym||Evax Diaperia +|
|Taxon name||Diaperia +|
|Taxon parent||Asteraceae tribe Gnaphalieae +|
|Taxon rank||genus +|
|Volume||Volume 19 +|