Cyanthillium Blume, 1826

Robinson, Harold, Skvarla, John J. & Funk, Vicki A., 2016, Vernonieae (Asteraceae) of southern Africa: A generic disposition of the species and a study of their pollen, PhytoKeys 60, pp. 49-126 : 59

Cyanthillium Blume, 1826 Figures 4 D–F ; 5 A–C

Cyanthillium Blume, Bidjr. 889. 1826. - Type: Cyanthillium villosum Blume

Isonema Cass., Bull. Soc. Philom. Paris 1817: 152. 1817, nom. illeg., non Isonema R. Br., 1810. - Type: Isonema ovata Cass.

Cyanopsis Blume ex DC., 5: 69. 1836, nom. illeg. superfl., non Cass. 1817.

Vernonia sect Tephrodes DC., Prodr. 5: 24. 1836. - Lectotype: Conyza cinerea Blume (Jones 1981a).

Claotrachelus Zoll. & Moritz ex Zoll., Natuur-Geneesk. Arch. Ned. Indie 2: 263, 565. 1845. - Type: Claotrachelus rupestris Zoll. & Moritz ex Zoll.

Seneciodes L. ex Post & O. Kuntze, Lex. Gen. Phan. 2: 515. 1903. - Type: Conyza cinerea L.

Triplotaxis Hutch., Bull. Misc. Inform. 1914: 355. 1914. - Lectotype: Herderia stellulifera Benth. in Hook. (Robinson 1990a).

Vernonia subsect. Tephrodes (DC.) S.B. Jones, Rhodora 83: 70. 1981.

Resources.

Traditionally treated as part of Vernonia .

Descriptions.

Annual or short-lived perennial herbs to 1 m tall; stems erect or spreading; hairs symetrically or asymetrically T-shaped with short stalk. Leaves alternate; petioles narrow; blades membranaceous, ovate to narrowly lanceolate. Inflorescences terminal, moderately densely to laxly branching, distinctly cymiform or with rather corymbiform branches, with minute bracteoles; peduncles rather short to elongate. Heads narrowly campanulate, involucral bracts ca. 30 in 3(-5) series, gradate, thinly chartaceous, green with pale or purplish margins, persistent, often with pilose to sericeous pubescence; receptacles epaleaceous. Florets 15-94 in a head; corollas bluish to lavender, funnelform with slender lower tubes, throat a third as long to nearly as long as lobes, lobes with simple hairs especially near tips; anthers without tails; apical appendages oblong-ovate, glabrous, with thin cell walls; style base with broad node; style branches with acicular sweeping hairs. Achenes 5-ribbed, or terete, setulae shortly cleft at tips, with idioblasts, sometimes with glands, raphids elongate; inner pappus of many long, sometimes rather fragile, slender-tipped capillary bristles, outer series of persistent squamellae, one species with callose ring. Chromosome number n = 9, 18, 20 ( Turner and Lewis 1965, Mathew and Mathew 1976, Jones 1979).

Pollen ca. 30 μm in diameter (dry); triporate, echinolophate, ca. 21 lacunae rather irregularly disposed at poles and in intercolpi; perforated tectum restricted to ridges of muri, with distinct microperforations; spinules of muri short, shorter than width of mural ridge, pointed, without columellae under each murus; baculae single at junctures of muri and no baculae between junctures, each intersection of muri with stout columella that is firmly attached to footlayer (Fig. 4 D–F ).

Notable secondary metabolites, 5-alkylcoumarins, sesquiterpene glaucolides, guanolides ( Bohlamnn and Jakupovic 1990, as Vernonia chinensis Less., Vernonia cinerea Less.).

Figures

Figure 4. Scanning electron micrographs of acetolyzed pollen of echinolophate Bothriocline and Cyanthillium and sublophate-lophate Distephanus. A-C Bothriocline schimperi Oliv. & Hiern ex Benth. A Equatorial view, note incipient colpus of 3 connected lacunae centered on pore B Near polar view C Fractured grain D-F Cyanthillium cinereum (L.) H. Rob. D Equatorial view E Lateral view with apertures on sides F Lateral view G-I Distephanus angustifolia (DC.) H Rob. & B. Kahn. G Polar view H Equatorial view I Lateral view. (A-C, F. Meyer 8159; D-F, Evans 344; G-I, Sidley 2211).

Figure 5. Photographs of Cyanthillium cinereum (L.) H. Rob: A Inflorescence, B habit, C Close up of heads in fruit. See Appendix C for citation details.