Stemodiopsis kamundii K.Balkwill, 2020

Balkwill, K., 2020, A revision of Stemodiopsis Engl. (Linderniaceae) in South Africa, South African Journal of Botany 135, pp. 377-383 : 381-382

2 Stemodiopsis kamundii K.Balkwill sp. nov.

Type: South Africa, Limpopo, 2229 (Waterpoort): Soutpansberg district , Farm Prince 758 MS , Medike , 980 m (DC), 10 Apr 1993, Balkwill & Balkwill 8262 ( J, holo.; E, PRE, iso.)

Perennial fruticose herb with woody base; densely puberulous with short (0.1 0.2 mm long), straight ornamented trichomes, stems possibly deciduous, initially erect, becoming pendent with age, up to 350 mm long. Leaves petiolate, blade ovate to elliptic, 4 14 X 3 11 mm, with (3) 4 or 5 (6) sharp or rounded teeth on each side of the margin, puberulous with short (0.1 0.2 mm long), straight, ornamented trichomes on both surfaces and especially on veins and margins, apex acute to obtuse, base cuneate and decurrent on petiole; petiole 4 12 mm long. In fl orescences of axillary, singleflowered cymes; peduncle 2.5 3.0 mm long; bracteoles filiform, 1.2 2.0 X 0.1 0.2 mm; pedicel 1.5 3 mm long. Calyx puberulous with spreading, straight, ornamented trichomes, some collapsing and some with small glandular heads, tube 0.5 mm deep, lobes lanceolate, 3.0 3.2 X 1.0 1.2 mm. Corolla tube white, 3.0 3.5 mm long, with straight to slightly curved, non-collapsing, ornamented eglandular trichomes on outer surface, upper lip 1.5 X 2.0 mm, fringed with hairs, glabrous on inner surface, lower lip with many collapsing thin-walled trichomes on inner surface and fringed with gland-tipped hairs, with a pronounced boss, lobes 0.5 X 1.0 mm, all three lobes purple. Stamens: anterior (abaxial) filaments, slightly curved at base, 3 mm long, anthers 0.7 mm long, posterior (adaxial) filaments 2.1 2.5 mm long. Ovary 2 mm long, style 4 6 mm long. Capsules reflexed, 4.5 5.0 X 2.5 3 mm, densely puberulous with short, broad or longer, ornamented trichomes. Seeds slightly curved, 1.0 X 0.3 mm.

Diagnostic characters: Stemodiopsis kamundii differs from S. rivae by having shorter hairs on the stem that are up to 0.2 mm long, ornamented and largely not collapsing ( Fig. 2C, F & G ), whereas S. rivae has hairs that are at least 0.3 mm or longer, not ornamented and often collapsing ( Fig. 2H & I ). The calyx lobes and capsules of S. kamundii have short ornamented trichomes ( Figs. 3D G ), whereas S. rivae has long trichomes on the calyx lobes and glabrous fruits ( Fig. 3C ).

Taxonomic notes: This species fits Philcox' s (1990) and Fischer' s (1997) description of S. buchananii var. pubescens , but is very different from the type of that variety [Grosvenor 327 (LISC011346, holo. seen on Global Plants; isotypes BR628590 seen on Global Plants, K000379579 seen on Global Plants, PRE!, SRGH!)], which has a dense stem indumentum of short (0.04 to 0.06 mm long), broad ornamented hairs ( Fig. 2B & E ). The epithet gives an impression of longer hairs, however, and is thus possibly the reason for many misdeterminations. The PRE sheet of van der Schijff 3571 is unusual in consistently having three flowers in each cyme and in having shorter, sparser hairs on the stems and fruits ( Figs. 2G & 3F&G ), but the KNP sheet of this gathering does not share the inflorescence character, and other specimens from the area (e.g. Zambatis et al. GZ776 & GZ830 (KNP)) have indumentum that is more consistent with other specimens of S. kamundii .

Etymology: Named for Dr Dickson Athanasius Ignasio Kamundi (1961 2007), a botanist employed at the National Herbarium and Botanic Gardens of Malawi at Zomba. He came to South Africa to study for honours and doctoral degrees at the University of the Witwatersrand as part of the Southern African Regional Botanical Network (SABONET) Project. During that period, he contributed to the assessment of South African vascular plants for the 2009 Red List ( Raimondo et al., 2009). He graduated with a Doctor of Philosophy on the phylogeny and taxonomy of Loudetia Hochst. ex Steud. (Poaceae) in 2007, but tragically died of malaria shortly after his return to Malawi.

Distribution and ecology: This species occurs in Zambia, Zimbabwe and the Limpopo province of South Africa ( Fig. 4). It occurs in crevices and cracks in boulders and rock faces, often where the boulders occur in the shade of a woodland.

Phenology: Stemodiopsis kamundii has been collected in flower and fruit from December through to April.

Conservation notes: Although the habitat of this species is very specialised, it is not suitable for economic activities and thus there are minimal threats. In addition, the species is known from more than 20 localities and from two countries, so that a provisional threat status of Least Concern (LC) is appropriate.

Additional specimens examined: Zambia. 1032: Chinsali district, 24.5 km NW of Isoka—Mpika road on road to Mbesum Ranch , 10° 5 ' 42'' S, 32° 22 ' 39'' E (AB), 22 May 1994, Schmidt et al. 1403 ( MO) . Zimbabwe. 1630: Darwin, Umvukwes , Umsengedzi River , 1400 m (DD), 22 Dec 1952, Wild 3935 ( MO, PRE, SRGH). 2028: Bulawayo, 1380 m (BA), 29 Jan 1934, Saunders Davies s.n. sub BM40806 ( BM) ; Matopo Hills, 1540 m (DA), Feb 1903, Eyles 1166 ( BM, PRE) ; 24 Feb 1981, Philcox & Leppard 8810 (K); on hills near Maleme Dam (DA), 30 Jan 1973, Ngoni 177 ( PRE, SRGH) ; Besner Kobila , 1450 m (DA), Feb 1954, Miller 2199 ( K) . 2029: Beitbridge district, Umzingwane River , Fultons Drift ( BB), 26 Feb 1961, Wild 5432 ( MO, PRE) . South Africa. LIMPOPO. 2229 (Waterpoort): About 5 km from Pontdrif to Alldays (AA), 22 Mar 2003, Jordaan 4056 ( PRE) ; Vhembe National Park , Greefswald , 22° 13 ' 4'' S, 29° 21 ' 23'' E, 579 m (AB), 12 May 2000, Mothogoane 285 ( PRE) ; Breslau 2MS farm , 1710 m (AC), 22 Jun 2001, Straub 941 ( PRE) ; Vivo, Soutpansberg , Bangor Farm , Lesheba Nature Reserve , 1451 m (DC), 15 Feb 1989, Venter 13,165 ( PRE) ; Outlook farm 789MS (DD), 21 Oct 1984, Jacobsen 3419 ( PRE); About 12 km NW of Louis Trichardt [Makhado], on Hanglip Mountain , 1764 m (DD), 3 Apr 1997, Burgoyne 6117 ( PRE). 2230 (Messina): About 15 km ENE of Louis Trchardt [Makhado] on the Witvlag road, Studholme Farm , 22° 56 ' 55'' S, 30° 1 ' 28'' E, 1450 m (CC), 4 April 1997, Burgoyne 6192 ( PRE); Jordaan 3210 ( PRE); Sibasa (CD), Junod 26,112 ( PRE) . 2231 (Pafuri): Kruger National Park , Pafuri , Seekoeigat (AC), 18 Feb 1954, van der Schijff 3571 ( KNP, PRE) ; Mutale Gorge , 22° 25 ' 55'' S, 31° 4 ' 5'' E (‒AC), 7 Jun 2013, Zambatis et al. GZ 830 ( KNP) ; Pafuri (‒AD), 28 Apr 1954, van der Schijff & Marais 3709 ( KNP, PRE) ; Punda Maria, Along S61 loop, on Xantangaleni , 22° 38 ' 40'' S, 31° 8 ' 12'' E (‒CA), 30 Jan 2006, Maurin & van der Bank OM861 ( KNP) ; Shantagalani Koppies , 22° 39 ' 3'' S, 31° 8 ' 32'' E (‒CA), 6 Jun 2013, Zambatis et al. GZ 776 ( KNP, PRE) . 2328 (Pietersburg): Blaauwberg, southern slopes , 1700 m (BB), 01 Jun 1953, Esterhuysen 21,428 ( BM, PRE) ; near old DC' s [District Commissioner' s] residence , 1170 m (BB), 29 Apr 1954, Codd 8734 ( PRE) ; Mohlakeng Plateau , 1630 m (BB), 13 Jan 1955, Codd & Dyer 9375 ( PRE); Farm Beauly 260LR , 1700 m (BB), 12 Oct 1991, Smook 7458 ( PRE) ; 23° 4 ' 59'' S, 28° 59 ' 26'' E, 1600 m (BB), 25 Dec 2012, Kremer-Kohne 681 ( PRE) . 2329 (Pietersburg): Soutpansberg , Louisville farm 33LS , 1600 m (AB), 23 May 1982, Venter 8738 ( PRE) ; Polokwane, Moletsi , top of Masoane Mountain, northern side (CB), 8 Jan 1995, Makgakga 128 ( PRE).

Figures

Fig. 2. Indumentum on stems of: A, D, Stemodiopsis buchananii var. buchananii, voucher Cron et al. 252 (J); B, E, S.buchananii var. pubescens, voucher Grosvenor 327 (SRGH); C, F, S. kamundii, voucher Balkwill & Balkwill 8262 (J); G, S. kamundii, voucher van der Schijff 3571 (PRE); H, I, S. rivae, voucher Pawek 12,752 (MO). Scale bars = 0.5 mm for A‒C & G‒H and 0.1 for D‒F & I.

Fig. 3. Indumentum on fruits of: A, Stemodiopsis buchananii var. buchananii, voucher Cron et al. 252 (J); B, S. buchananii var. pubescens, voucher Grosvenor 327 (SRGH); C, S. rivae, voucher Pawek 12,752 (MO); D, E, S. kamundii, voucher Balkwill & Balkwill 8262 (J); F, G, S. kamundii, voucher van der Schijff 3571 (PRE).Scale bars = 1 mm for A‒D & G and 0.2 mm for D & E.