Rubus mundtii Chamisso & Schlechtendal (1827: 18)

Beek, Abraham Van De, 2021, Rubi Capenses: a further contribution to the knowledge of the genus Rubus (Rosaceae) in South Africa, Phytotaxa 515 (1), pp. 1-71 : 33-35

12. Rubus mundtii Chamisso & Schlechtendal (1827: 18)

Homotypic synonym:— Rubus rigidus var. mundtii (Cham. & Schltdl.) Harvey & Sonder (1862: 287) .

Type:— SOUTH AFRICA. Western Cape: ‘In promontorio bonae spei ad Hangklipp legerunt Julio 1821 Mund et Maire’, Mundt & Maire s.n. (the number 224 is written on the label by Schlechtendal) ( B 10 1146998 [https://www.jacq.org/detail.php? ID =1627315]) .

Note on name: —The correct spelling of the epithet is ‘mundtii’. The family name is Mundt, as Dr. Uwe Braun in Halle kindly informed me.

Primocane ( Figs 10A–C ) arching, diam. 4–7 mm, angular and furrowed, with dense short grey hairs; prickles 5–15 per 5 cm from 4–8 mm broad base compressed, hooked or with geniculate tip, up to 4–8 mm long, densely short hairy; stipules 7–15 mm, linear-lanceolate, hairy. Leaves with flat margin, 3-foliolate or bi-jugate pinnate, sometimes with lobate or divided basal leaflets, adaxially with some to moderately dense short appressed hairs, abaxially ( Fig. 10D ) densely grey to white tomentose; serrature triangular, hardly to short mucronate, clearly short periodical; petiole 5–7 cm long, densely hairy, with 10–13 curved or hooked prickles; central leaflet of 3-foliolate leaves 55–60 mm long, broad ovate with emarginated or subcordate base, gradually short pointed, width–length index 0.78–0.87, length of petiolule 38–43% of length of leaflet; central leaflet of 5-foliolate leaves 39–60 mm long, (ob-)ovate-elliptical with rounded base, acute or sometimes emarginated at tip, width–length index 0.57–0.71, length of petiolule 14–30% of length of leaflet; petiolule of lateral leaves 0–4 mm. Flowering branch ( Figs 10E–F ) angular and furrowed, with dense short hairs and sessile glands; prickles 4–20 per 5 cm, unequal, from 2–6 mm base compressed to almost subulate, curved and hooked, up to 4–6 mm long. Leaves 3- to 5-foliolate or upper simple, adaxially with some to dense short appressed hairs, abaxially densely white tomentose; serrature sharper than at primocane leaves. Inflorescence ( Fig. 10G ) with rigid axis, with 2–8 axillary branches or fully leafy, with dense, narrow cylindric apex, densely hairy with patent stellate hairs and with curved and hooked prickles; peduncles divided from base or in middle, longest ones with 5–8 flowers; pedicels 0–8 mm, densely hairy, often with some prickles. Flowers: sepals erect, 3–4 × 5–8 mm, short pointed, densely grey tomentose; petals pink or white, small, roundish; stamens shorter than styles; anthers glabrous; styles red; ovaries with few short stellate hairs; receptacle with long hairs. Ripe fruit black ( Fig. 10H ).

Ecology: —Roadsides, open fields.

Distribution: —Widespread in South Africa and Lesotho. The typical form from Hangklip eastward to the Van Stadens Pass. Similar forms at many places in the eastern and northern provinces. In spite of extensive searches in the region of Hangklip, the species could not be found there again. A good match was found in hedges along the road from Swellendam to Suurbraak, where it grows together with other forms of Rubus ser. Scleri .

Specimens:— SOUTH AFRICA. Western Cape: along the road from Swellendam to Suurbraak, 13 January 2020, Beek 2020.05 (L); Swellendam, in utroque litore Buffelsjagrivier ab Swellendam ad Rietkuil, s. dat., Zeyher 2450 (PRE, ‘ Rubus chrysocarpus’, not all specimens under this number are identical); Wilderness, Fairy Know, at the Ebb and Flow River, 13 January 1929, Mogg 11740 (PRE). Eastern Cape: Humansdorp, Clarkson, October 1926, Thode A822 (PRE, ‘ R. fruticosus var. bergii’); Near Van Stadens Pass, 14 January 1949, Theron 568 (PRE).

Taxonomy: —The typical form has very strong, compressed, hooked prickles, adaxially moderately hairy leaves and straight teeth with short mucros. From the Van Stadens Pass eastward plants occur with less compressed only curved prickles ( Fig. 11A ), adaxially denser hairy leaves and with very fine almost fringed serrature with long mucros ( Fig. 11B ). It was given the provisional name ‘ R. sclerus ’ ( Fig. 11C ). However, many intermediate plants were found and it was not possible to find consistent combinations of characteristics for separating both forms. Different characteristics were sometimes found at the same plant, so that more research is needed before these plants can be conceived as an accepted taxon.

Specimens of the eastern form:— SOUTH AFRICA. Gauteng: Heidelberg, 26 December 1907, Leendertz 1069 ( L.1913163) . Free State: Golden Gate, Wodehouse Kop, April 1972, Jacobs 8557 ( PRE) ; Clarens, road to Golden Gate, short before entrance of the park, south side of the road, 17 February 2019, Beek 2019.37 ( L) ; Fouriesburg, Dunelm, 8 January 1918, Potts 6683 ( PRE) . KwaZulu-Natal: Spioenkop memorial, parking, 16 February 2018, Beek 2018.18 ( L) . Eastern Cape: ‘ In mont. supra Van Stadensriver’, Zeyher 66 = On the banks of Zwartkops River and on the hills of Adow , Oct. , Zeyher 4 ( NBG) ; ‘ Ad ripam fluminis ‘ Zwartkopsrivier’ et in collibus (alt. I-III) terrae ‘ Adow’ (Uitenhage), tum in Albany et Kafferland’, Ecklon & Zeyher 1709 ( L.1913162, PRE, other samples of Ecklon & Zeyher 1709 may be different); Uitenhage, Van Stadens Pass, 15 January 2020, Beek 2020.10 ( L) ; Galgebosch (locality code IV C c 9), Drège s.n. ( HBG 503845 ) ; East London, 1888, Thode 10440 ( NBG) .

— LESOTHO: Mamathes , 15 April 1949, Guillarmod 868 ( PRE) .

Note: —Also plants with other different characteristics, such as patent straight prickles, white petals, abaxially glabrous leaves, or incised leave margins, were found. In the studied region such plants are rare, but their occurrence increase to the east and north, especially in northern KwaZulu-Natal, where they are abundant. The precise relation of all these diverging forms must be subject of future research.

Figures

FIGURE 10. Rubus mundtii. A. Primocane with leaves. B. Primocane. C. Primocane. D. Leaf, abaxially. E. Flowering branch. F. Flowering branch. G. Inflorescence. H. Fruits. Photographs: A. van de Beek.

FIGURE 11. Rubus sclerus. A. Primocane. B. Pedicels. C. Herbarium specimen (Beek 2018.18). Photographs: A. van de Beek.