Three new species of Semiria ( Proteaceae ) from the southwestern Cape

Three new species of Serruria are described, namely, S. altiscapa Rourke from the Villiersdorp and Hottentots Holland Mountains, characterised by its unusually tall paniculate inflorescences; S. qremialis Rourke. a multistemmed lignotuberous species with adaxially cygneous, basally pubescent styles and cylindric pollen presenters from the Villiersdorp and Houhoek Mountains as well as the north slopes of the Riviersonderend Range, and S. balanocephala Rourke. a single-stemmed re-seeding species from the north slopes of the Langeberg. distinguished by its adaxially cygneous, basally pubescent styles and conic-acute


INTRODUCTION
Serruria Salisb.. is the largest genus of the South Afri can Proteaceae which is endemic to the southwestern and southern Cape.The most recent comprehensive account of the genus recognised 48 species and listed a further 18 as 'imperfectly known species' (Phillips & Hutchinson 1912).Exploration of mountainous areas of the Cape dur ing the present century has brought a number of new taxa to light, several of which have already been described (Rourke 1982(Rourke , 1990(Rourke , 1991)).This paper enumerates an other three new species of Serruria prior to the preparation of a complete account of the genus.S e rru ria altiscapa Rourke.sp.nov., a S. williamsii Rourke habitu humili compacto.inflorescentiis paniculatis peraltis 7(H)-1 2(X) mm.bracteis glabris transversoovatis m anifeste alatis, perianthioque p ro xim aliter utriculoso differt.
Serruria altiscapa is also related to 5. elongata (P.J. Bergius) R. Br.On Blokkop above Villiersdorp they occur sympatrically and flower simultaneously, yet there is no evidence of hybridisation, suggesting that there is a strong genetic barrier between the two species.
The annual vegetative growth increments in this spe cies are rather short resulting in a low, compact, rounded form in mature plants.In early winter certain vegetative shoots produce a terminal peduncle 700-1 200 mm long which develops into a large panicle of capitula with sec ond order branching.By early June the capitula begin opening, in centrifugal succession, continuing until matu rity in November, by which time a new, short, vegetative growth flush commences.An axillary bud below the fruit ing inflorescence develops into a new, short vegetative shoot which then terminates in a further inflorescence the following winter.As the peduncles are highly lignified they persist for several years on the adult plants before decaying.In some plants these lignified peduncles may persist for from three to four years before disintegrating.each consisting of approximately 300 plants, occur on the middle south slopes of Blokkop above Villiersdorp and about 15 km to the west; there are a few smaller popu lations on the lower south slopes of the Hottentots Holland Mountains in the Viljoen's Pass-Nuweberg area (Figure 4A).Serruria altiscapa grows in mesic mountain fynbos on south-facing slopes at elevations between 700 and 1 100 m.Flowering commences in early June, reaches a peak in August and continues until October.Fruits are shed during November and December.
Distribution and habitat: this species occupies a variety of habitats in the Breede River valley from Stettynsberg along the southern foothills of the Villiersdoip Mountains to Viljoen's Pass, the northern foothills of Groenlandberg.Houhoek and eastwards along Ezeljacht to the Caledon Swartberg.However, its main area of distribution occurs on the northern slopes of the Riviersonderend Mountains from Donkerhoek and Boskloof in the w est eastwards to McGregor reaching Bushman's River at its most easterly limits.Isolated populations also occur on Sandberg near Robertson (Figure 4B).Most populations occur in mesic mountain fynbos at elevations between 270 and 760 m.
Flowering extends over a period of almost eight months, from July to February but is dependant on local factors such as site, aspect and elevation.
Serruria gremialis is a relatively common and wide spread species which was collected as early as the 1830's by Zeyher at Houhoek but was not subsequently recog nised as distinct.Meisner (1856) misidentified Zeyher's collection from Houhoek and cited it under S. elevata R. Br. (= 5. fucifolia Salisb.ex Knight).Later, in the Flora capensis, Phillips & Hutchinson (1912) cited material be longing to no less than four different species under their concept of 5. acrocarpa R. Br., including what is here described as S. gremialis.It is therefore not surprising that since then herbarium material of the species now known as S. gremialis has been identified under a number of dif ferent names, particularly as S. incrassata Meisn.and 5. acrocarpa R. Br.
The distribution ranges of S. gremialis and S. acro carpa are contiguous and almost mutually exclusive ex cept at one site, namely Silverstream near Boskloof in the western Riviersonderend M ountains where they grow sympatrically (Rourke 2000(Rourke , 2002)).
Diagnostic characters: Serruria balanocephala is a single-stemmed re-seeder, with an erect, upright habit at taining 1 m in height at maturity with terminal peduncu late capitula.It is distinguished by its adaxially cygneous style, puberulous in the lower half, the conic-acute, slightly faceted pollen presenter and villous perianth.
Distribution and habitat: this species has a rather re stricted distribution along the northern slopes of the Langeberg Range.It occurs from a few kilometres south east of Montagu, eastwards to Barrydale and thence to Brandrivier just west of Garcia's Pass, a distance of ap proximately 80 kilometres, but has not been recorded east of Garcia's Pass (Figure 4B).Serruria balanocephala ap pears to be confined to a narrow belt of dry mountain fynbos, at elevations of approximately 600 to 650 m in the lower northern foothills of the Langeberg, fringing the Little Karoo.Flowering takes place between late August and November.The inflorescences are pinkish silvery and have no perceptible scent.
The epithet balanocephala is a compound from the Greek balunosy an acorn, and cephale, a head, alluding to the distinctive ovoid-acute form of the pollen presenter.
FIGURE 3.-Serruria altiscapa Rourke.Complete plant showing ha bit.Current season's inflorescence and persistent lignified re mains of inflorescences from three previous flowering seasons are evident.Type material.Rourke 1971.