Research Article |
Corresponding author: Vincent Ralph Clark ( vincentralph.clark@gmail.com ) Academic editor: Alexander Sennikov
© 2016 Vincent Ralph Clark, Joanne Bentley, Anthony P. Dold, Vathiswa Zikishe, Nigel P. Barker.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Clark VR, Bentley J, Dold AP, Zikishe V, Barker NP (2016) The rediscovery of the Great Winterberg endemic Lotononis harveyi B.–E.van Wyk after 147 years, and notes on the poorly known Amathole endemic Macowania revoluta Oliv. (southern Great Escarpment, South Africa). PhytoKeys 62: 1-13. https://doi.org/10.3897/phytokeys.62.8348
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South Africa’s 800 km-long southern Great Escarpment hosts numerous endemic plant species only known from their type specimens or from very few records. This is a legacy of a 100–150 year lag between the pioneer work of 19th century botanists and repeat fieldwork in the 21st century. As a result, population and ecological data are lacking for many local endemic species. Here we report on the rediscovery of Lotononis harveyi B.–E.van Wyk 147 years after its original description, and provide the first detailed ecological notes on the poorly known shrub Macowania revoluta Oliv. Both species are locally endemic to the Great Winterberg–Amatholes (Eastern Cape Province). With only six known individuals, L. harveyi is recommended the conservation status of Critically Endangered, with fire (and potentially grazing) being the main population constraints. Macowania revoluta is locally abundant, and it is surprising that it has been so poorly collected in recent decades. It occupies an important local niche as a keystone montane wetland species, and its narrow distribution range – combined with pressure from woody alien invasive species – suggests that its conservation status should be Rare. The research further highlights the need for continued biodiversity field research along South Africa’s poorly explored Great Escarpment.
Lotononis harveyi , Macowania revoluta , Great Winterberg, Amatholes, endemic, rediscovery, fieldwork, Red Data status, Great Escarpment, South Africa, Eastern Cape
The ‘Cape Midlands Escarpment’ (comprising the Sneeuberg, Great Winterberg–Amatholes (GWA) and Stormberg, mostly in the Eastern Cape Province, South Africa) has been part of a southern Great Escarpment biodiversity research focus since 2005 (
Here we provide detailed notes on two of these poorly-known GWA endemics: Lotononis harveyi B.–E.van Wyk, rediscovered 147 years after its description in Flora Capensis, and first-time population and ecological data for Macowania revoluta Oliv., last reliably collected some 40 years ago.
Described by William Harvey in Flora Capensis as Buchenroedera spicata Harv. in 1862 (
Extensive fieldwork by VRC in the Great Winterberg in January 2009 for his PhD resulted in the first recollection of this species since its publication in Flora Capensis, although this was not realised at the time. The specimen (Clark VR, Pienaar C, Daniels R 316;
The 2009 site (hereafter Locality 1) was relocated without difficulty, and the search extended southwards down the 19th century wagon trail to the trigonomic beacon and eastwards to the edge of Paradise Kloof (part of the Fenella Falls gorge complex), covering approximately one square kilometre. Despite exploring the area carefully (in the plateau grassland and along the edge of the ravine, as well as in the fynbos and grassland on the steep slopes of the ravine) only six individual plants were found (three in flower, three not).
The first ever photographs of the Great Winterberg–Amatholes endemic Lotononis harveyi B.–E.van Wyk A flower detail (Clark VR, Bentley L 9) B habit (Clark VR, Bentley L 9; the Garmin GPS indicates scale) C montane grassland habitat, with L. harveyi in the middle foreground (Clark VR, Bentley L 11) D complete and open inflorescences (Clark VR, Bentley L 12). Photographs by V.R. Clark.
The 2009 specimen was assigned to L. harveyi on the basis of the elongated racemes (therefore not L. trichodes (E.Mey.) B.-E.van Wyk, another local Great Winterberg endemic); the white flowers with densely hairy petals (based on the label information and a few remaining petals on the specimen, as the plant was mostly in pod); the long calyx lobes, hirsute leaves, and long stipules (which match
The plants at the three localities are described separately:
In 2009, two plants were found and collected at Locality 1, recorded as ca. 50 cm tall and with white flowers. This site occupies two square meters and is located on the two meter-wide ‘middle man’ between the 19th century wagon trail over the Great Winterberg and the current Finella Falls farm access road. In November 2014, at the same site, three plants were found. One was 45–50 cm tall, branched and in full flower. The other two were 15 cm and 5 cm tall respectively, both damaged on their main axes (probably being the two specimens collected in 2009, one lodged in the Selmar Schonland Herbarium,
If the two smaller plants recorded in November 2014 at Locality 1 are indeed the survivors of the two 2009 vouchers, their limited growth since then suggests that the species grows extremely slowly, and this may partly account for its apparent rarity. In contrast, it is surprising that there is no obvious evidence of recruitment despite the floribund inflorescences.
Generally speaking, L. harveyi occurs in Amathole Montane Grassland (
Locality 1 consists of a very small area of moribund Themeda triandra Forssk. grassland. Other species present in this area are Cliffortia sp. (50–60 cm tall), Luzula africana Drège ex Steud. and Fingerhuthia sesleriiformis Nees. The remainder of the road reserve comprises the invasive tree Populus × canescens (Aiton) Sm.. The soil is deep and clayey. No plants were evident in the grassland on either side of the road reserve: these grasslands comprise well-gazed Themeda triandra grassland studded with tall Festuca costata Nees tussocks. The gradients are gentle, soils deep and rich, there is limited rockiness, and the grass is probably burnt on a regular basis to limit the spread of the unpalatable Festuca costata.
Locality 2 comprised (prior to burning) Tenaxia disticha (Nees) N.P.Barker & H.P.Linder (=Merxmuellera disticha (Nees) Conert)–Themeda triandra–Festuca costata grassland with the fynbos elements Erica leucopelta Tausch, Searsia rosmarinifolia (Vahl) F.A.Barkley, and shrubs/trailers such as Rubus ludwigii subsp. ludwigii and R. rigidus Sm.. The edge of the plateau comprises rocky sandstone outcrops favoured by the fynbos elements, while away from this the soil is a deeper, loamy clay.
Locality 3 comprises moribund Tenaxia disticha–Themeda triandra–Festuca costata veld with scattered Arrowsmithia styphelioides DC. dwarf shrublets and Helichrysum splendidum (Thunb.) Less.. Fire has evidently been absent for some time.
Mrs Barber’s
Lotononis harveyi is currently listed as Data Deficient (
The general area is vulnerable to invasion by Rosa rubiginosa L. (a fast-emerging invader, with several seen in Localities 1 & 3) and Pinus patula Schltdl. & Cham. (Locality 2), while Locality 1 is in danger of being overrun by Populus × canescens. The targeting of mountain environments for wind farms in South Africa is another concern, with potentially detrimental impacts on localised endemics such as L. harveyi.
A more exhaustive search along the rugged, extensive rocky rims of the Fenella Gorge area and perhaps on the (still unexplored) slopes of Mount Frederick and Besterskop (the promontory below the main Great Winterberg peak) and the scarp slopes below The Ruitjies might produce more plants. In fact, much of this area has still to be explored botanically, particularly from Mount Frederick–Besterskop eastwards along the scarp below The Ruitjies. The relevant localities/properties are summarised as follows (taken from 1:50 000 sheet 3226AD Spring Valley): Finella Falls 1 (parts of this farm were well surveyed in 2009, but there are extensive rocky areas not yet explored); the scarp margins on the Bosch River Spruit 26; Petraea 2 (being the south-western slopes of Mount Frederick and Besterskop); Oribi Fountains 3 (also being the south-eastern slopes of Mount Frederick and Besterskop, as well as the south-facing scarp of The Ruitjies); and those portions of Emerald Hill 26 and adjacent farms that comprise the ‘Groenberg’.
South Africa, Eastern Cape Province, 3226AD, Farm Emerald Hill 26, Great Winterberg (Adelaide): grassland in road reserve on farm track towards Fenella Falls. 32°22'34"S, 26°20'28"E, 1616 m, 23 January 2009. Clark VR, Pienaar C, Daniels R 316 (
—Eastern Cape Province, 3226AD, Farm Emerald Hill 26, Great Winterberg (Adelaide): grassland in road reserve on farm track towards Fenella Falls. 32°22'25"S, 26°20'24"E, 1649 m, 6 November 2014. Clark VR, Bentley L 9 (=Locality 1; the same population as above, but the 2009 GPS and altitude were a generic reading taken for plant collections along the entire road, and are not as accurate as these provided here. Only photographs were taken of these plants).
—Eastern Cape Province, 3226AD, Farm Bosch River Spruit 26, Great Winterberg (Adelaide): plateau grassland. 32°23'42"S, 26°21'04"E, 1616 m, 6 November 2014. Clark VR, Bentley L 11 (
—Eastern Cape Province, 3226AD, Farm Emerald Hill 26, Great Winterberg (Adelaide): moribund grassland on the plateau. 32°23'42"S, 26°21'04"E, 1619 m, 6 November 2014. Clark VR, Bentley L 12 (=Locality 3; only photographs were taken of these plants).
Macowania revoluta, the type species of Macowania, was first collected by Peter MacOwan in the eastern part of the Amatholes sometime prior to 1870 and described by Daniel Oliver in Icones Plantarum (
The first concrete records of this species’ continued existence was a collection in July 2010 by JB and Nicola Bergh (Compton Herbarium) in the vicinity of Keiskammahoek (Locality 1 – the closest record to the type locality), followed by a second specimen in October 2010 by APD near the Madonna & Child Waterfall in Hogsback (Locality 2). Following this, in December 2014, the species was found by VRC to be abundant in the central Amathole mountains along the Amatola Hiking Trail (Localities 3–5). In March 2015 another plant was recorded by VZ from Isidenge State Forest on the road to Evelyn Hut (one of the overnight huts on the Amatola Hiking Trail; Locality 6).
The poorly known Great Winterberg–Amatholes endemic Macowania revoluta Oliv. A a capitulum showing the distinctive dark involucral bract margins (Bentley J 1) B shrubby, candelabra growth-habit (above Wolf River Main Forest along the Amathole Hiking Trail, specimen not collected) C detail of flowering stem (Bentley J 1) D young plant showing ruderal tendencies (Clark VR 451). Photographs by C. McKune (A), V.R. Clark (B, D) and N. Bergh (C).
The plant is typically an erect, candelabra-like shrub 50 cm to three metres tall, but often lax and weedy when small. The leaves are distinctly linear, dark green, sticky glandular and sweetly aromatic with strongly revolute margins (hence its specific name) and a raised abaxial midrib. Both disc and ray florets are yellow, with the ray floret petals rounded upwards. The involucre is bell-shaped with distinctly long bracts; the margins are strikingly dark-brown.
Another species endemic to the GWA, Arrowsmithia styphelioides – earlier believed by
At Locality 1, M. revoluta was found to be locally abundant, with plants in excess of one meter in height and forming the dominant species. Only one plant was noted at Locality 2, growing on the edges of a derelict Pinus patula plantation and Acacia mearnsii De Wild. invasions. Locality 3 contained about 20 plants, 0.5–1 m tall, with two in flower and many others in seed. Locality 4 comprised a large colony (ca. 50 m × 100 m in extent) with M. revoluta (1–3 m tall) forming the dominant species; many were in flower. Locality 5 consisted of a dense but small colony (1–3 m tall) covering ca. 50 m × 10 m; also with many in flower. Only one plant was located at Locality 6, and was not in flower.
Based on the information on the type material,
Macowania revoluta is currently listed as Data Deficient (
Macowania revoluta potentially occurs anywhere along the wet southern scarp of the Amathole Mountains, between Katberg Pass and Stutterheim. So far it has not been recorded on the adjacent Great Winterberg.
(a selection of these is mapped in Figure
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): summit of Pirie mountains, Kaffraria. 1200 m (4000'), October 1884. Leighton (J?) 225 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): summit of Mount Pirie. May 1887. Tyson W 2935 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Perie (=Pirie), Kaffraria. August 1892. Sim TR s.n. (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Pirie. 1200 m (4000'), September 1892. Sim TR 3283 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Summit of Perie (=Pirie). 900 m (3000'), November 1893. Flanagan HG 2144 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Summit of Perie (=Pirie) mountains. 11th September 1901. Galpin EE 5930 (
—Eastern Cape Province, 3226DB, Amathole Mountains (Victoria East): Hogsback, common in scrub. January 1920. Rattray G 304 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Keiskammahoek): Wolf River Plateau, forest margins in scrub. 29th October 1921. Stayner FJ 28 (
—Eastern Cape Province, 3226DB, Amathole Mountains (Cathcart): Hogsback. September 1925. Pole Evans IB 1748 (
—Eastern Cape Province, 3226DB, Amathole Mountains (Stockenstrom): hillside above forest at Hogsback. 28th October 1946. Esterhuyse E 13,249 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Wolf Ridge, Hogsback. 1200 m (4000'), 10th September 1947. Story R 3119 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Keiskammahoek): Wolf River Forest. 18th September 1947. Dyer RA 104 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Keiskammahoek): Gwili-Gwili Mountain, old military road to Evelyn Valley. 25th April 1949. Story R 3797 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Keiskammahoek): No details. 1976. Gibbs Russell s.n. (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): summit of Mount Pirie. No date. Macowan P 9053 (
—Eastern Cape Province, 3226BC, Katberg (Fort Beaufort): no details. No date. Macowan P s.n. (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Pirie. November, no year. Sim TR 1029 (
—Eastern Cape Province, 3227CA, Amathole Mountains (King Williams Town): Pirie. No date. Sim TR 3130 (
South Africa, Eastern Cape Province, 3227CA, Amathole Mountains (Stutterheim): between isiDengi Forest Station and Evelyn Valley Forestry Station. 32°43'32"S, 27°14'30"E, 1208 m, 27th July 2010. Bentley J 1 & 5 (
—Eastern Cape Province, 3226DB, Amathole Mountains (Cathcart): above Madonna & Child Waterfall, Hogsback, 32°36'27"S, 26°57'47"E, 1106 m, 7th October 2010. Dold T 15,010 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Stutterheim): about one kilometre from Dontsa Hut on the Amatola Hiking Trail (Day 2 from Maden Dam side): in an earth road drain on the edge of a pine plantation next to a forestry road. 32°35'46"S, 27°13'29"E, 948 m, 3rd December 2014. Clark VR 450 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Stutterheim): about five kilometres from Dontsa Hut towards Cata Hut on the Amatola Hiking Trail (Day 3 from Maden Dam side): montane fynbos and streams banks. 32°34'40"S, 27°10'31"E, 1371 m, 4th December 2014. Clark VR 451 (
—Eastern Cape Province, 3227CA, Amathole Mountains (Stutterheim): along the Amatola Hiking Trail towards Zingcuka Hut (Day 5 from Maden Dam side): along a cliff top above Wolf River Main Forest. 32°34'03"S, 27°05'04"E, 1259 m, 6th December 2014 (=Locality 5; only photographs were taken, by VRC).
—Eastern Cape Province, 3227CA, Amathole Mountains (Stutterheim): from Isidenge State Forest on the road to Evelyn Hut. 32°43'29"S, 27°14'37"E, 1198 m, 15th April 2015. (=Locality 6; only photographs were taken, by VZ).
VRC wishes to thank his field assistants in 2009 (Ryan Daniels, Charl Pienaar) and 2014 (Luke Bentley), as well as Larry King and Arthur Moorcroft for permissions to access their private properties in the Great Winterberg. Dave Scott and Larry King are thanked for their kind farm hospitality. The research results were part of two post-graduate studies: a PhD (VRC) supported by the National Research Foundation (NRF, grant GUN 2069059), the South African Biosystematics Initiative (SABI, 2006–2009), the National Geographic Society (USA) Committee for Research and Exploration (grant 8521-08), Buk’Indalo Consultancy cc, a Dudley D’Ewes Scholarship from the Cape Tercentenary Foundation; and a M.Sc. (JB) also supported by the NRF (SABI grant 71072 and an NRF Masters bursary). This paper was constructed during a NRF Scarce Skills Post-doctoral Fellowship (VRC, 2014–2016). The material was collected under permits issued by Eastern Cape Department of Environmental Affairs.