Massonia elandsmontana J.C.Manning, 2021

Manning, J. C., 2021, Massonia elandsmontana (Hyacinthaceae: Scilloideae), a new species from the Swartland of Western Cape, South Africa, South African Journal of Botany 141, pp. 142-144 : 143-144

Massonia elandsmontana J.C.Manning , sp. nov.

Type: South Africa, Western Cape, Worcester (3319): Bo-Hermon, Elandsberg Nature Reserve , 500 m S of Secretarybos Road and 100 m W of Bosplaas Road , (— AC), 5 Oct 2020 [fruiting], J. Manning 3800 ( NBG, holo.; PRE, iso.) .

Deciduous geophyte. Bulb subglobose to ovoid, 20 — 30 mm diam., outer tunics leathery, greyish to pale brown. Leaves 2, opposite, blades spreading-appressed, broadly elliptic to suborbicular, 30 — 60 X 25 — 45 mm, upper surface green, ± densely pubescent with erect hairs mostly 0.5 — 1.0 mm long, margins densely ciliolate with short stiff bristles 0.2 — 0.3 mm long. In fl orescence a condensed, subcapitate raceme, few[5- to 10]-flowered], flowers protruding shortly above leaves; bracts oblanceolate, 12 — 15 X 2 — 5 mm, apiculate-aristate, margins minutely ciliolate distally; pedicels at anthesis 3 — 4 mm long, elongating to 10 mm in fruit. Flowers white, lily-scented; perianth tube narrowly cylindrical, 7 — 8 X 1.5 — 2.0 mm; tepals arising ± at same level, spreading or weakly suberect, without sigmoid coiling, straight or ± incurving distally, linear, 5 — 6 X 1 mm, conduplicate, margins entire, apex penicillate. Filaments suberect, white, filiform, unequal, outer ± 8 mm long, inner 6.0 — 6.5 mm long, connate at base for 0.8 — 1.0 mm, mouth not occluded by interstaminal gibbosities or invaginations; anthers ± 1 mm long at anthesis, blackish purple with blue pollen. Ovary oblong-conical, pale yellow, 2 mm long, tapering and weakly contracted to style, with 3 ovules per locule; style white, 14 mm long, weakly differentiated from ovary, erect, slender. Capsules oblong, 3-winged when fully formed but often only two locules fertilised, cordate-intrusive basally, (7 —)8 — 10 X (5 —) 7 — 8 mm. Seeds globose, ± 1.8 mm diam., smooth, glossy black. Flowering time: May. Figs. 1 , 2 .

Distribution and ecology: a highly local endemic from the western foot of the Elandskloof Mtns of Western Cape, known from a single population on the Elandsberg Nature Reserve ( Fig. 3 ); on seasonally moist, stony, loamy alluvium in Swartland Alluvial Fynbos ( Mucina and Rutherford, 2006). The population occupies a very restricted habitat in relatively open shrubland dominated by Eriocephalus africanus L. ( Asteraceae ), occurring at the interface between two thicker fynbos communities dominated respectively by Leucospermum calligerum (Salib. ex Knight) Rourke ( Proteaceae ) on drier sandy soils and Leucadendron corymbosum P.J.Bergius ( Proteaceae ) on seasonal wetland, and a third renosterveld shrubland community dominated by Elytropappus rhinocerotis (L.f.) Less. ( Asteraceae ) on heavier clay soils. The population comprises an estimated 30 to 40 plants, of which ± 10 were in flower in each of the two seasons that they were studied in the field. Extensive searches over the adjacent veld did not reveal further sub-populations and it seems that the species is restricted to this single locality, a situation that is mirrored in Brunsvigia elandsmontana and Pelargonium elandsmontanum , both of which occupy the same vegetation type.

Seed set seems to be relatively low, with most capsules developing only 1 or 2 seeds in one or two locules but the seeds that are developed are evidently well-formed and plump. This suggests some form of pollinator limitation.

Diagnosis: the species is distinctive in the genus in its pubescent foliage, the otherwise smooth adaxial surface covered with short, erect hairs 0.5 — 1.0 mm long and the margins densely ciliolate with shorter bristles, with a few-flowered inflorescence of small, white, hypocrateriform flowers with slender perianth tube 7 — 8 mm long. The narrow, spreading tepals without sigmoid coiling, unequal filaments with blackish anthers and blue pollen, and the style weakly differentiated from the ovary place M. elandsmontana in a small alliance of species from the West Coast and near-interior of western Cape that includes the two coastal species M. inaequalis W.F.Barker ex Martt. -Azorín et al. and M. dregei Baker and the inland-montane M. pygmaea Schlecht. ex Kunth. The very small capsules, up to 10 mm long, are also consistent with this alliance. Massonia elandsmontana is readily distinguished from these species by the distinctive vestiture of the leaves, viz. the combination of longer, softer hairs on the otherwise smooth (not pustulate) adaxial surface with short marginal bristles. It is most likely to be confused with M. pygmaea , which is florally very similar, but that species has characteristic foliage with a pustulate or muricato-pustulate adaxial surface and minutely setulose margins.

Conservation notes: Massonia elandsmontana is known from a single small population on the Elandsberg Nature Reserve, comprising less than 50 individuals. Although the species has a minimal area of occupancy, its only known population lies within a formal conservation area, without evident threats. A conservation status of Critically Rare (known from a restricted area but without any known threat) is proposed.

Additional specimen seen

South Africa. Western Cape. 3319 (Worcester): Bo-Hermon, Elandsberg Nature Reserve, Secretarybos Road , (— AC), 2 Aug 1997 [past flowering], E. Parker 160 ( NBG); 500 m S of Secretarybos Road and 100 m W of Bosplaas Road , 27 May 2016, J. Manning 3584 ( NBG) .

Figures

Fig. 1. Massonia elandsmontana. A, flowering plants and plant in bud; B, detail of leaf surface and margin vestiture; C, bract; D, flowers; E, half-perianth detail showing unequal stamens and mouth of perianth tube not occluded; F, gynoecium; G, capsules; H, seed. Vouchers: Western Cape, Elandsberg Nature Reserve, Manning 3584 (A—F) and Manning 3800 (G, H). Scale bar: A, G, 10 mm; C—F, 2 mm; B, H, 1 mm. Artist: J. Manning.

Fig. 2. Massonia elandsmontana, flowering plant. Voucher: Western Cape, Elandsberg Nature Reserve,Manning 3584. Photographer: J.Manning.

Fig. 3. Distribution of Massonia elandsmontana.