Vernoniastrum H. Rob., 1999

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 : 93-94

publication ID

https://dx.doi.org/10.3897/phytokeys.60.6734

persistent identifier

https://treatment.plazi.org/id/1BB3366D-B68A-1839-57F8-280407E5B4AF

treatment provided by

PhytoKeys by Pensoft

scientific name

Vernoniastrum H. Rob., 1999
status

 

Vernoniastrum H. Rob., 1999 Figures 23 F–G View Figure 23 ; 25 D–I View Figure 25

Vernoniastrum H. Rob.. Proc. Biol. Soc. Wash. 112(1): 233. 1999. - Type: Crystallopollen latifolium Steetz in Peters.

Vernonia sect. Lepidella Oliv. & Heirn, Fl. Trop. Afr. 3: 267. 1877, non Lepidella Tiegh. 1912 or Lepidella E.J. Gilbert 1925. - Type: Vernonia petersii Oliv. & Hiern.

Vernonia subsect. Lepidella (Oliv. & Hiern) S.B. Jones, Rhodora 83: 72. 1981.

Descriptions

. Annual or perennial herbs 0.3-1.0 m tall; stems pilose, hairs simple with elongate apical cells with slightly asymmetric bases. Leaves alternate. Inflorescence with 1-many heads. Involucre campanulate; involucral bracts ca. 50 in ca. three series, gradate, persistent; receptacle epaleaceous. Florets ca. 50 in a head; corollas reddish-purple, basal tube narrowly funnelform, throat shorter than lobes or anther thecae, lobes pilosulous distally; anther bases acuminate to acutely tailed; apical appendage glabrous, with thin cell walls. Style base with node; style branches with acicular sweeping hairs. Achenes 4-6-angled, setulae aparse on sides, idioblasts usually grouped in transverse bands, raphids elongate; pappus bristles subpersistent, marginally densely barbellate; outer squamae persistent. Chromosome number n = 10 ( Jones 1979, 1982).

Pollen triporate, lophate, perforated tectum discontinuous in lacunae, muri papillate, with or without micropunctations on muri (Fig. 25 D–I View Figure 25 ).

With habit similar to Polydora but often perennial, lacking L-shaped hairs, having tailed anther bases, and a chromosome number n = 10. Also characteristic of the core element of Vernoniastrum are the transverse bands of crowded idioblasts in the achene walls.

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Asterales

Family

Asteraceae

Loc

Vernoniastrum H. Rob., 1999

Robinson, Harold, Skvarla, John J. & Funk, Vicki A. 2016
2016
Loc

Vernonia petersii

Oliv & Hiern ex Oliv 1873
1873