Austronea (Asparagaceae, Scilloideae), a new genus from southern Africa, including the description of seven new species
Author
Martínez-Azorín, Mario
Author
Crespo, Manuel B.
Author
Alonso-Vargas, María Ángeles
Author
Dold, Anthony P.
Selmar Schonland Herbarium, Department of Botany, Rhodes University, Grahamstown 6140, South Africa.
Author
Pinter, Michael
Institute of Biology, Division Plant Sciences, NAWI Graz, Karl-Franzens University Graz, Holteigasse 6, A- 8010 Graz, Austria.
Author
Wetschnig, Wolfgang
Institute of Biology, Division Plant Sciences, NAWI Graz, Karl-Franzens University Graz, Holteigasse 6, A- 8010 Graz, Austria.
text
Phytotaxa
2018
2018-08-21
365
2
101
129
http://dx.doi.org/10.11646/phytotaxa.365.2.1
journal article
10.11646/phytotaxa.365.2.1
1179-3163
13704788
5.
Austronea olifanta
Mart.
-Azorín, M.B.Crespo, M.Pinter & M.A.Alonso
sp. nov.
(
Fig. 11
)
Ab
Austronea barkerae
affinis foliorum characteribus, sed hac diversa nempe foliis minus numerosis
1–4
(nec
3–9
), a basi nec angustatis nec pseudopetiolatis, in maturitate glabrescentibus vel fere glabris (nec manifeste pilosis); floribus albidis (nec pallide brunneolis), ovario
2.8–3.1 mm
long. (nec ca.
1.8 mm
long.) et stylo longiore
1.8–2 mm
long. (nec ca.
1 mm
long.).
Type
:—
SOUTH AFRICA
.
Western Cape
.
Clanwilliam
(3218): ca.
6 km
south of
Clanwilliam
, near Clanwilliam-Citrusdal-Cederberg road crossing (-
BB
), elev.
124 m
,
23 September 2015
(in flower),
M
. Martínez-Azorín,
M
.
B
. Crespo,
M
.
A
. Alonso &
M
. Pinter MMA1170
(
holotype
,
GRA
!;
isotype
,
ABH74854
!)
.
Herbaceous deciduous geophyte. Bulb hypogeal, solitary, ovoid to subglobose, 11–25 ×
10–26 mm
, extended into a short hypogeal neck up to
1.5 cm
long, with pale brown membranous outer tunics and white fleshy tightly packed inner tunics. Roots fleshy, white, branched, 5–40 ×
0.7–1 mm
. Leaves 1–4, rosulate, sessile, withered or almost withered at flowering time, aerial portion 15–35 ×
2–8 mm
, from narrowly lanceolate to ovate-lanceolate with acute apex in young leaves to obovate with obtuse apex in older leaves, flattened, slightly canaliculated, green, somewhat leathery, smooth, young leaves distinctly hairy and ciliate, with somewhat retrorse hairs
0.5–1 mm
long, older leaves wider and nearly glabrous, although usually sparsely hairy along the lower portions, prostrate to suberect, with a white hypogeal leaf portion connecting to the bulb neck. Inflorescence nodding in bud, raceme
2–4 mm
long, capitate or subcorymbose, with 4–21 flowers; peduncle
9–24 cm
long, erect, flexuose, distinctly papillose on the lower half; pedicels
2–5 mm
long at anthesis, spreading, smooth; bracts ovate-lanceolate, ca.
1 mm
long, clasping the pedicels, spurred, the lowermost with a spur up to
2.5 mm
long, membranous, white with a central darker band. Flowers pentacyclic, trimerous, stellate, opening about noon and withering in the evening, only 1–2 flowers open at a time, flower buds white-green; tepals 6, entire, white on the adaxial side with a green longitudinal central band on the abaxial side, slightly glandulous at the apex, biseriate, outer overlapping inner at the base, connate for ca.
1.5 mm
to form a cup, free portions patent; outer tepals ovate, 3.8–4.6 ×
1.8–2 mm
, with margins only slightly revolute at anthesis; inner tepals oblong, 3.7–4.4 ×
1.7–1.9 mm
, more or less flat. Stamens 6, suberect or slightly spreading, adnate to perigone for ca.
1 mm
; filaments white, fleshy, subterete and attenuate to the apex, 2.6–2.8 ×
0.4 mm
, smooth; anthers yellow, oblong, ca.
1 mm
long before dehiscence, dehiscing by longitudinal slits, with yellow pollen. Ovary yellowish to pale green, ovoid, somewhat truncate to the style, 2.8–3.1 ×
1.5 mm
; style white, columnar,
1.8–2 mm
long, slightly contrated at the middle, trigonous in transversal section; stigma small and slightly papillate. Capsule and seeds unknown.
FIGURE 11.
Austronea olifanta
Mart.
-Azorín
et al.
from S of Clanwilliam, (type locality), Western Cape, South Africa in flower on 23 September 2015 corresponding to
MMA1170
and in leaves on 24 July 2016 corresponding to
MMA1490-1491
.
A.
Inflorescence;
B.
Flowers, frontal and dorsal views;
C.
Dissected flower in lateral view;
D.
Plants in flower;
E.
Withered leaves at flowering time;
F.
Young plants in leaf;
G.
Mature plants in leaf. Scale bars: A–C: 5 mm; D–G: 1 cm.
Etymology
:—Named after the Olifants River valley where the
type
locality of
A. olifanta
is located near Clanwilliam in the
Western Cape Province
of
South Africa
.
Phenology
:—
Austronea olifanta
flowers around September in the wild at the
type
locality and leaves are present in July–August.
Habitat
:—This species grows on sandy soil derived from Table Mountain sandstone on rocky ground with open vegetation classified as FFs3 Olifants Sandstone Fynbos, with mean annual precipitation ranging from
250–700 mm
, peaking May to August, with 3–10 days of frost per year (
Mucina & Rutherford 2006
).
Distribution
:—
Austronea olifanta
is only known from the surroundings of Clanwilliam and Pakhuis Pass in the
Western Cape Province
(
Fig. 10
).
Diagnostic characters and taxonomic relationships
:—
Austronea olifanta
is characterized by the 1–4, sessile, lanceolate to obovate, flattened to slightly canaliculate leaves, distinctly hairy in young plants with cilia of
0.5–1 mm
long, and almost glabrous in older mature plants but usually shortly hairy along the lower portions; inflorescence subcorymbose on an elongate peduncle; tepals white on the adaxial side with a green central band on the abaxial side,
3.7–4.6 mm
long, connate for ca.
1.5 mm
to form a cup, and patent free portions. Inflorescence, flower size and morphology of
A. olifanta
resemble those of several species in the genus, such as
A. barkerae
,
A. ecklonii
,
A. marginata
,
A. pulchromarginata
,
A. trichophylla
and
A. vermiformis
. However, leaf morphology of these species is clearly different (
Manning & Goldblatt 2003
,
2007
,
Martínez-Azorín
et al.
2016
). Among them,
A. trichophylla
and
A. barkerae
show hairy leaves, however
A. trichophylla
differs from
A. olifanta
by the single, narrowly linear, thickened leaf and is restricted to the surroundings of Grahamstown in the
Eastern Cape Province
. The closest species to
A. olifanta
is
A. barkerae
with respect to the leaf and flower morphology, but the latter differs by the more numerous (3–)5–7(–9) leaves, which are narrowed into a pseudopetiole, always distinctly hairy at least on the abaxial surface in mature plants, the pale-brownish flowers, smaller ovary ca.
1.8 mm
long and shorter style ca.
1 mm
long (
Manning & Goldblatt 2003
). Moreover,
A. barkerae
is endemic to the Piketberg Quartz Vygieveld (SKk8)—a very restricted vegetation unit characterised by quartz patches with slightly saline soils, as they are the quartz patches of Knersvlakte, within the succulent karoo unit, whilst
A. olifanta
is found in sandstone fynbos.
Additional material
studied (
paratypes
)
:—
SOUTH AFRICA
.
Western Cape
.
Clanwilliam
(3218):
Pakhuisberg
,
Clanwilliam
,
L
.
C
.
Leipoldt
(
BOL
!)
;
Clanwilliam
(3218):
Karroo
hills
Pakhuis
, also
Clanwilliam
, common,
L
.
C
.
Leipoldt
(
B100167492
!)
;
Clanwilliam
(3218):
In
arenosis prope
Clanwilliam
,
300 feet
,
2 October 1897
,
H
.
Bolus
9103
(
BOL
!)
;
Clanwilliam
(3218):
Clanwilliam
division,
N
of Citrusdal
,
16 October 1935
,
L
.
E
.
Taylor
1225
(
BOL
!)
.