Three new species and one new subspecies of Euryops (Asteraceae: Senecioneae) from the Klein Karoo in the Western Cape Province, South Africa.
Author
Vlok, J. H. J.
text
South African Journal of Botany
2020
2020-09-30
133
167
173
http://dx.doi.org/10.1016/j.sajb.2020.07.025
journal article
286104
10.1016/j.sajb.2020.07.025
108593c9-fd23-4fa7-80b2-61df903bb150
1727-9321
10496796
3.2.
Euryops bertilii J.H.J.Vlok
,
sp. nov
Euryops vlokii
B
.Nord
. ms. (
Manning and Goldblatt, 2012
)
Type:
South Africa
,
Western Cape Province
, Ladismith (3320):
Anysberg Nature Reserve
, about
2 km
south of old
Allemorgensfontein
railway station, (-CB),
650 m
,
8 July 2006
,
Vlok
&
Schutte
550
(
NBG
holo.;
S
, iso)
.
Densely branched shrublet up to
30 cm
tall (
50 cm
when flowering, due to the long peduncles); young branches densely leafy, older branches covered with almost cork-like remnants of leaf bases.
Leaves
erect, with tips spreading, 10—20 X
3—6 mm
, mostly simple, occasionally with up to five uneven lobes 2—4 x ca.
2 mm
, obtuse to acuminate, glabrous, with small woolly tuft in axil of leaf bases, glaucous-green.
Peduncles
lateral in upper leaf axils,
120—200 mm
long, terete, ca.
1 mm
thick.
Involucre
hemispherical to widely cup-shaped,
7—12 mm
diam.
Involucral bracts
uniseriate, 10 to 12, glabrous, free to base, lanceolate, 6—7 X
2—3 mm
wide, 3-veined, purplish in distal half with paler membranous margin, acuminatepenicillate.
Ray
fl
orets
10; corolla yellow, tube cylindrical,
2 mm
long, lamina oblong,
8—10 mm
long, 4-veined; style branches erect, spreading,
1 mm
long.
Disc
fl
orets
ca. 60; corolla yellow,
4 mm
long; tube cylindrical,
2 mm
long; limb campanulate,
2 mm
long with triangular-acute lobes.
Anthers
2 mm
long with ovate appendage.
Style
terete, branches spreading, ca.
1 mm
long, papillate at the tip.
Pappus
bristles white, numerous,
2 mm
long.
Mature achenes
not seen, ovaries of ray-and disc-florets papillate. (
Plate 2
).
Flowering period: July
Distribution and ecology:
Euryops bertilii
is known only from the Ladismith district where it occurs in Succulent Karoo vegetation, more specifically in the Western Little Karoo unit
sensu
Mucina and Rutherford (2006)
. At a finer scale
Vlok and Schutte-Vlok (2015)
described this vegetation as Kalkveld, a vegetation unit that is restricted to large outcrops of calcrete with very little topsoil.
Diagnosis:
Euryops bertilii
belongs to the sect.
Angustifoliae
as pappus bristles are present on the ray and disc florets and the peduncles are axillary on the stems. It is most similar to
E. namaquensis
Schltr.
and
E. cuneatus
B.Nord.
, but differs in the involucral bracts that are free to the base and the leaves that are not 3-partite, with most leaves simple and only some basal leaves with up to five unevenly sized lobes (involucral bracts basally connate for a third to half their length in
E. namaquensis
and leaves apically 3-lobed and lateral leaf lobes often forking in
E. cuneatus
).
E. namaquensis
is restricted to Namaqualand and
E. cuneatus
occurs from Calvinia southwards to Laingsburg.
Conservation notes:
The
species is known only from the
type
locality, where it occurs occasionally in an area of about 150 ha (
Fig. 3
).
The
plants were very heavily browsed by domestic stock previously, but have recovered well since the property was included in the
Anysberg Nature Reserve
in 2000.
Following
Raimondo et al. (2009)
,
I
propose a conservation status of
Endangered
(
C2
(a) (ii)) for this species.
Etymology:
The species is named for Prof. Bertil Nordenstam (born
20th February 1936
,
Sweden
) to honour his work on the genus
Euryops
and his other contributions to the flora of
South Africa
.
3.2.1. Changes to species key
This species can be accommodated in the existing key to sect.
Angustifoliae
(
Nordenstam, 1968: 38
) by changing couplet 66 to the following:
(i) Involucral bracts free to base; leaves simple or unevenly lobed...
E. bertilii
(ii) Involucral bracts not as above.. ... ... ... ... ... ... .. continue with existing key.