A taxonomic revision of Inulanthera (Asteraceae: Anthemideae) *
Author
Magoswana, S. L.
Author
Boatwright, J. S.
Author
Manning, J. C.
Author
Magee, A. R.
text
South African Journal of Botany
2016
2016-07-31
105
141
157
http://dx.doi.org/10.1016/j.sajb.2016.02.203
journal article
10.1016/j.sajb.2016.02.203
1727-9321
10496274
Inulanthera
KällersjÖ
in Nord. J. Bot. 5 (6): 539 (1986);
Bremer & Humphries in Bull. Bri
t. Mus
. (Nat. Hist.), Bot. 23: 95 (1993).
Type
:
I. calva
(Hutch.)
KällersjÖ (=
I. dregeana
(DC.)
KällersjÖ).
Single to multi-stemmed shrubs,
0.3–2 m
tall, usually resprouting from a woody caudex or rarely reseeding; stems sub-erect, simple or branched from near base or in upper half,
1–8 mm
diam., striate, glabrous or sparsely lanate.
Leaves
alternate, sub-erect to incurved or spreading to recurved, linear to obovate or pinnatisect to bi-pinnatisect, 2–70 ×
1–40 mm
, entire, dentate or serrate; base tapering or cuneate to auriculate, plane or margins revolute, glabrous to villous or whitish woolly, sometimes ± discolorous, glandular-punctate, coriaceous; axillary shoots absent or developed in upper or lower leaves.
Capitula
homogamous, in sparse or dense compound corymbs
15–130 mm
across; inflorescence branches
5–40 mm
long, sometimes with primary branches
15–40 mm
long and secondary branches
3–35 mm
long; inflorescence bracts linear to elliptic or lanceolate, 2–10 ×
1–9 mm
.
Involucre
campanulate or subglobose, 3–10 ×
3–12 mm
, involucral bracts 3- to 5-seriate, glabrous to pubescent or cobwebby to densely whitish woolly, conspicuously orange gland-dotted; outer bracts ovate to elliptic or lanceolate, 2–10 × 0.5–3.0 mm, obtuse to acuminate or attenuate, serrulate.
Receptacle
conical, paleate or rarely epaleate (
I. nuda
only).
Florets
bisexual, 20 to 75, yellow; corolla funnel-shaped, 5-lobed, glandular, tube ± as long as limb.
Anthers
tailed, apical appendages ovate, endothecial cells polarized.
Style
terete with thickened base, branches truncate, papillate apically.
Cypselas
obconic or obovoid, 1.0–2.5 × 0.5–1.0 mm, prominently 7- to 10-ribbed, brownish-gold, glabrous to scabrid, sessile glands sometimes present between ribs (
I. dregeana
and
I. tridens
); non-myxogenic.
Pappus
formed by ribs extended apically into small horns or scales 0.2–0.5 x ±
0.5 mm
, scales sometimes becoming broadly membranous and basally connate.
Diagnostic characters
Inulanthera
shares tailed anthers with the shrubby South African genus
Osmitopsis
but is distinguished from that genus by the discoid capitula (generally in corymbs) and apically papillate, linear styles.
Osmitopsis
is characterised by conspicuously radiate capitula with white ray florets and apically penicillate, linear to oblong styles.
Distribution and ecology
Nine species distributed in
South Africa
from
Eastern Cape Province
through
KwaZulu-Natal
and
Free State
, extending to
Lesotho
and
Swaziland
, with a single species endemic to either
Angola
(
Inulanthera schistostephioides
),
Madagascar
(
I. brownii
) and
Zimbabwe
(
I. nuda
). Occurring on mountain slopes in thick grassland, on forest margins and bush clumps or along streams, often on dolerite, sandstone or basalt.
Key to the species of
Inulanthera
1. Primary leaves without axillary leaf tufts or shoots:
2. Plants single-stemmed; leaves glabrous, sessile, ovate to lanceolate and sharply serrate …………………………………….........
4.
I. leucoclada
2′. Plants multi-stemmed; leaves pubescent, at least beneath, narrowed at base or petiolate, obovate to elliptic, entire or variously lobed but not sharply serrate:
3. Leaves pinnatisect; involucral bracts rounded; endemic to
Angola
……….………………………………
7.
I. schistostephioides
3′. Leaves entire to 2- or 3-lobed, involucral bracts attenuate or obtuse; widespread in
South Africa
,
Lesotho
and
Swaziland
:
4. Straggling shrublets; leaves narrowly oblong to elliptic, entire or 3-lobed with lanceolate lobes; involucral bracts attenuate with dark apices ………………………….
9.
I. tridens
4′. Stout rounded shrubs; leaves linear or deeply 2- or 3-lobed with linear lobes; involucral bracts obtuse without dark apices ………………………...………………………………...........
8.
I. thodei
Fig. 3.
Known distribution of
Inulanthera brownii
.
1′. At least upper primary leaves with axillary leaf tufts or shoots:
5. Leaves pinnatisect:
6. Receptacle paleate; involucral bracts glabrous; leaves
≤
8 mm
long by
≤
2 wide; endemic to
South Africa
………………………
2.
I. coronopifolia
.
6′. Receptacle epaleate; involucral bracts pubescent; leaves
≥
10 mm
long by
≥
5 mm
wide; endemic to
Zimbabwe
………………...
6.
I. nuda
5′. Leaves entire, or variously lobed but never pinnately cut:
7. Leaf margins sharply and regularly serrate to base; leaves and involucral bracts glabrous ………….…………………………….
5.
I. montana
7′. Leaf margins lobed or serrate in distal half only; leaves and involucral bracts cobwebby to glabrescent:
8. Leaves sub-erect, obovate to oblanceolate, 3- to 10-crenate or -dentate in distal half,
4–15 mm
wide, base attenuate; endemic to
Madagascar
……………………………………………………
1.
I. brownii
8′. Leaves spreading to recurved, oblong to narrowly ovate, 3- to 5-lobed,
3–5 mm
wide, base cuneate; endemic to
South Africa
…………………………………………………….
3.
I. dregeana
.