A review of the Geissorhiza namaquensis (Iridaceae: Crocoideae) group with the new species G. namaquamontana from Northern Cape, South Africa *
Author
Goldblatt, P.
Author
Manning, J. C.
text
South African Journal of Botany
2017
2017-07-31
111
299
301
http://dx.doi.org/10.1016/j.sajb.2017.03.041
journal article
10.1016/j.sajb.2017.03.041
1727-9321
10496412
1.
G. namaquensis
W.F. Barker
in Fl. Pl. S. Afr. 18: t. 688 (1938).
Type
:
South Africa
,
Northern Cape
, Springbok (2917):‘Namaqualand, Klipfontein’, (–BA), flowered ex hort. Kirstenbosch,
Jul. 1931
,
Phillips s.n.
(BOL [
BOL22163
], holo.!).
Plants mostly
160–300 mm
high.
Corm
± globose,
8–15 mm
diam., slightly asymmetric with one side obliquely flattened below; tunics dark brown, imbricate, notched below into ± regular segments, drawn into points above.
Stem
suberect or inclined, flexed at base of spike, puberulous, sometimes only below, simple or 1(2)-branched.
Leaves
3(4), lower 2 basal, ± as long as stem,
2–5 mm
wide, third leaf cauline, shorter, sheathing below, fourth leaf, if present, shortest and scale-like, blades narrowly lanceolate with margins raised and narrowly winged, main vein also raised, margins and edges of main and sometimes secondary veins ciliate.
Spike
inclined, flexuose, mostly 3- to 7-flowered; bracts green, becoming dry, membranous and pale brown distally, outer mostly
8–12 mm
long, inner smaller.
Flowers
actinomorphic, salver-shaped, blue to bluish mauve with white throat, perianth tube green outside; perianth tube cylindric, widening near throat, (7–)
8–11 mm
long, shortly exceeding bracts; tepals elliptic, 14–18 ×
3–6 mm
.
Filaments
erect, equal,
5–6 mm
long; anthers (4.5–)5.0–7.0 mm long, pale yellow or white; pollen pale yellow or white.
Style
dividing opposite middle to upper third of anthers, often tilted downward, branches ±
2 mm
long.
Capsules
broadly ovoid, (5–)
6 mm
long.
Seeds
not known.
Flowering time
: mid August to late September.
Fig. 1.
Geissorhiza namaquamontana
, Rooiberg,
Helme
3310
(NBG). Photograph: Nick Helme.
Distribution and ecology
: a
Northern Cape
endemic, recorded from the escarpment west of Kamieskroon, the Spektakel Mtns west of Springbok, and near Steinkopf; in rocky ground, on sandstone and shale substrates.
Diagnosis
:
G. namaquensis
is recognized by the moderate-sized, blue to bluish mauve flowers with perianth tube
7–11 mm
long and tepals 14–18 ×
3–6 mm
, and puberulous leaves with raised, narrowly winged margins and main and secondary veins, all ciliate on the edges (
Table 1
). The stamens of
G. namaquensis
are relatively long, with filaments
5–6 mm
long and anthers 4.5–7.0 mm long. The new
G. namaquamontana
has notably smaller flowers, with a slightly shorter perianth tube
6–7 mm
long, tepals (6–)8–10 × 1.5–2.0 mm, filaments
4–5 mm
long, and anthers
2–3 mm
long.
G. kamiesmontana
, restricted to the Kamiesberg, has dark violet flowers with a longer perianth tube,
18–25 mm
long, and tepals 16–20 × ±
3 mm
(
Table 1
).
Additional specimens seen
South Africa
.
NORTHERN CAPE
.
2917
(
Springbok
): Steinkopf, stony hillside, (–BA),
24 Aug 1959
,
Lewis 5494
(NBG); Steinkopf,
900 m
, (–BA),
Aug 1925
,
Marloth 6782
(B, BOL, NBG, PRE); Kosies NW of Steinkopf, (–BA),
Van Berkel 399
(MO); west of Springbok on slopes at eastern end of Spektakel Pass, among rocks, (–DA),
11 Sep 1993
,
Goldblatt &
Manning 9705
(NBG, PRE);
28 Sep 1974
,
Goldblatt 2803
(K, MO, NBG, PRE);
15.25 miles
W by S of Springbok, renosterveld, S aspect, (–CA),
24 Sep 1957
,
Acocks 19580
(K, M, NBG, PRE). Without precise locality: near Port Nolloth, ex hort.
28 Aug 1991
,
Williamson 3722
(NBG).
3017 (Hondeklipbaai):
Skilpad Flower Reserve, Namaqualand broken veld, (–BB),
24 Aug 1993
,
C.J. Grobler 57
(PRE).