Massonia obermeyerae Mart.

Martínez-Azorín, Mario, Dold, Anthony P., Pinter, Michael, Slade, Julian M., Crespo, Manuel B., Milkuhn, Gottfried & Wetschnig, Wolfgang, 2015, Massonia obermeyerae (Asparagaceae, Scilloideae), a new species from South Africa, Phytotaxa 205 (1), pp. 39-50 : 42-48

Massonia obermeyerae Mart. -Azorín, A.P.Dold, M.Pinter & Wetschnig spec. nova ( Figs. 3−6 ).

Species notabilis combinatione unica characterum ab ceteris speciebus Massoniae differt inflorescentia subsessili, densa, subcapitata, pedunculo atque rachidi clavatis, leviter incrassatis demum parce elongatis; filamentis plerumque rubescentibus, superne versus stylum incurvatis, inferne triangulari-incrassatis, a basi in tubum brevem ca. 1 − 1.5 mm supra perigonium connatis, et ad apicem leviter incrassatis distincte albicantibus; ovario a latere viso pentagonali, a vertice viso acutissime triquetri; stylo incrassato, sursum gradualiter desinente et ad apicem lateraliter flexo; capsula ante dehiscentiam cum carnosulo et crassiusculo longe persistente appendice coronata.

Type:— SOUTH AFRICA. Eastern Cape, Graaff-Reinet (3224): Pearston, farm Cranemere (- DB), July 1962, E. Jenkins (= E. Palmer) s.n. sub PRE 29302 (holotype PRE barcode 0049588-0!, only the plant on the upper half of the sheet corresponding to material collected in the wild in July 1962).

Deciduous geophyte. Bulb ovoid to subglobose, tunicate, ca. 15 − 30 × 15 − 25 mm, inner tunics fleshy and white, outer tunics thin, hardened and brownish. Leaves 2, deciduous, opposite, spreading and appressed to the ground, synanthous, ovoid, ovate-lanceolate or suborbicular with obtuse apex, 6 − 15 × 4 − 8 cm, margins narrow, membranous, minutely denticulate; adaxial side glabrous, smooth, usually wrinkled, dark grey-green, usually with scattered oblong, longitudinally-disposed purple maculae, margin purple; abaxial side smooth, green. Inflorescence a subsessile, dense, subcapitate raceme, 10 − 30 × 30 − 50 mm, with 6 − 25 flowers, shortly extending above ground level at anthesis. Peduncle and axis of inflorescence clavate and slightly swollen, somewhat lengthening with age. Bracts ovate to suborbicular, 11 − 20 × 10 − 25 mm, membranous, green with a purple flush in the upper half and white below, glabrous, with minutely denticulate margins. Pedicels 5 − 12 mm long, lengthening in fruit up to 16 mm. Flowers with a wide funnel-shaped tube and cucullate free portions of tepals. Perigone white with flushes of green and purple; perigone-filaments tube 3 − 5 × 4 − 5 mm, not concealing the ovary; free perigone segments triangular-ovate, outer whorl overlapping the inner at base, 4 − 6 × 2 − 4 mm, straight at first, suberect to spreading at anthesis and slightly reflexing later, without a strong sigmoid curve at the base. Filaments white to rose with a purplish flush, 8 − 10 mm long, distinctly arcuate-incurved towards the style, swollen and triangular below, tapering up to the apex, but slightly thickening again near the anther junction with a distinct white zone, connate at the base for ca. 1 − 1.5 mm above the perigone and forming a distinct swollen ring; anthers ca. 2 mm long, oblong, yellow before dehiscence, turning blue-violet after dehiscence near connective, dorsifixed, with yellow pollen. Ovary greenish with a purplish tinge above, ca. 4 × 3 mm, pentagonal in lateral view, triangular with acute edges in apical view, clearly differentiated from the style. Style greenish with a purple tinge, thickened, gradually tapering to the apex and hooked or bent on one side at the tip, 6 − 8 mm long, ca. 1 mm wide at the base. Capsule green with a purple tinge, subpentagonal to obovate in lateral view, trigonous with sharp edges in apical view, 11 − 15 × 14 − 18 mm, dry capsule with large, truncate valves, which are disposed on slightly elongated pedicels, with a persistent, fleshy, thickened, long-lasting style. Seeds subglobose, apiculate, black, 1.5 − 1.8 × 1.3 − 1.5 mm, smooth or slightly rugose.

Eponymy:—The specific epithet ‘ obermeyerae’ honours Anna Amelia Obermeyer (1907 − 2001), South African botanist who studied several genera of Hyacinthaceae in southern Africa contributing significantly to the knowledge of the family. Particularly, her detailed studies and comments on the morphology of the new Massonia from Cranemere farm are hereby acknowledged.

Biology:—Leaves of Massonia obermeyerae are present from May to July in wild populations, plants flower from July to September, and capsules develop from September to October. Flowers produce copious nectar and an intense agarose-like or yeasty scent. In the Klipplaat population, plants of M. obermeyerae grow beneath and on the southfacing edges of karoo bushes and also along dry stream beds, where additional moisture is available. The shallow, sour-smelling flower of Whiteheadia bifolia , also borne close to the ground, has been postulated to be pollinated by terrestrial rodents ( Manning et al. 2002) and now confirmed by Wester et al. (2009) and Wester (2011). Similarly, Johnson et al. (2001) confirmed this pollination strategy in Massonia depressa . The smell and flower morphology of M. obermeyerae also points to pollination by terrestrial rodents, though this has not yet been confirmed. Should this be the case, M. obermeyerae could represent one of the few Massonia species pollinated by rodents in eastern South Africa. The dry infructescences of M. obermeyerae bear dehiscent capsules with large open truncate apical lobes, probably to allow for wind dispersal like a tumbleweed. Evidence of this was observed in the Klipplaat population where complete infructescences were caught amongst nearby bushes and stones. This strategy is probably also present in the M. depressa aggregate of species, which show similar capsules.

Distribution:—The new species is known to us from four main areas in South Africa. In the Northern Cape, it occurs in the surroundings of Kimberley. In the Eastern Cape it grows in the Graaff Reinet, Pearston (Cranemere farm), Klipplaat-Steytlerville and Darlington Dam (previously called Lake Mentz) areas. In the Western Cape M. obermeyerae is known from two regions, one in the Gamkaberg Nature Reserve of the Little Karoo, south of Calitzdorp, and the other near Hermanus ( Fig. 7 ). It is worth mentioning that the collection by Stayner from “Hermanus coast line” was identified by W.F. Barker as Whiteheadia sp. nov. and a different later annotation in pencil reads “ Massonia grandiflora Lindl. (not matched at B.H.)”, and question marks are placed before and after the locality of the plant, expressing doubt about the cited locality.

Habitat:— Massonia obermeyerae mostly grows in karroid habitats of between 200 and 700 m in elevation and with ca. 250 mm of mean annual precipitation, although the population from Kimberley reaches 1200 m elevation and the one from Hermanus occurs along the coastline. Mean annual rainfall in the latter two areas can reach ca. 500 mm. The population from Kimberley grows in the Savanna Biome, Kimberly Thornveld (SVk4), with summer and autumn rainfall averaging 300 − 500 mm per annum and very dry winters with frequent frosts. The populations from Graaff Reinet, Pearston and Klipplaat occur in the Nama-Karoo Biome, Eastern Lower Karoo (NKl2) and the one from Darlington Dam in the Albany Thicket Biome, Sundays Noorsveld (AT5). Rainfall in these localities mainly occurs in late summer and early autumn, with a main peak in March. Mean annual precipitation ranges from ca. 150 − 350 mm with the mean around 256 mm. The population near Steytlerville grows in the Succulent Karoo Biome, Willowmore Gwarrieveld (SKv12). This area shows a bimodal (autumn/spring) rainfall pattern with a slight optimum in March and again from October to November, with an overall mean annual precipitation of 250 mm. The population from south of Calitzdorp is located in the Albany Thicket Biome, Gamka Thicket (AT2) sensu Mucina & Rutherford (2006), the driest of the thicket types, with a non-seasonal rainfall pattern between 102 − 545 mm, with a mean annual precipitation of 267 mm. Frost is fairly common in this region. The population from Hermanus grows in the Fynbos Biome, Overberg Dune Strandveld (FS7) with mostly winter rainfall with 400 − 600 mm of mean annual precipitation ( Mucina & Rutherford 2006).

Taxonomic relationships:— Obermeyer (1965) suggested that the plants from Cranemere farm could constitute the link between Massonia and Whiteheadia on the basis of the very short broad perigone-tube, the broad triangular exposed ovary, and the rachis of the inflorescence slightly elongating when cultivated. We independently reached the same conclusion and we add further characters shared between Massonia obermeyerae and Whiteheadia bifolia . Flowers of both taxa show strongly incurved filaments, which are thickened and tapering to the tip, although they are again swollen in the region of the white and spongy anther connective (as also indicated in a sketch of the plant from Cranemere farm made by Obermeyer and kept at GRA). Furthermore, the fleshy unripe capsules in both taxa bear a persistent, thickened, hooked, long-lasting style, whilst in most Massonia species the style is soon senescent although it usually also persists on top. The hypothesis that M. obermeyerae constitutes a link between Massonia and Whiteheadia agrees with our preliminary phylogenetic studies (not shown), in which M. obermeyerae is early branching and sister to other Massonia species, suggesting that a common ancestor of this species gave rise to the genus Massonia . Our studies also place several samples of W. bifolia as a monophyletic clade sister to the clade comprising M. obermeyerae plus the remaining Massonia species. Massonia obermeyerae also resembles taxa of the M. depressa species complex (cf. Jessop 1976, van der Merwe 2002, Knippels 2011), based on the similar flower structure with wide open perigone-tube, from which M. obermeyerae differs by characters shared with W. bifolia , such as the incurved filaments being white and slightly swollen at the tip, or the fleshy, thick, long-lasting style on top of the capsule. Moreover, Massonia depressa is mainly restricted to Namaqualand and the Western Cape province, whereas the distribution of M. obermeyerae is centred in the Eastern Cape province, with disjunct populations in the Western Cape near Calitzdorp and Hermanus and a further disjunct population near Kimberley in the Northern Cape. The new species was identified as M. grandiflora by Obermeyer (1965) though apparently with some doubt based on her own comments, as detailed above. In any case, M. grandiflora was synonymised with M. depressa by van der Merwe (2002) and Müller-Doblies & Müller-Doblies (1997) and therefore it differs from M. obermeyerae by the same characters as M. depressa . The M. depressa species complex still needs a careful revision to evaluate its taxonomic boundaries.

Additional specimens and material studied (paratypes):— SOUTH AFRICA. Northern Cape, Kimberley (2824): Kimberley, September 1912, Moran s.n. ( GRA!) ; Eastern Cape, Graaff-Reinet (3224): Graaff Reinet , August 1917, Francis s.n. ( GRA!) ; Eastern Cape, Graaff-Reinet (3224): Pearston, farm Cranemere (- DB), collected 1961, flow. Div. of Bot. July 1962, Prinshof P7133 , E. Jenkins PRE29302 ( PRE barcode 0049588-0!) ; Eastern Cape, Graaff-Reinet (3224): Pearston dist., farm Cranemere (- DB), collected 1961, August 1963, painted by Mrs. Stutterheim, E. Jenkins PRE29302 ( PRE barcode 0049589-0!) ; Eastern Cape, Steytlerville (3324): Klipplaat (- AB), 300 m south of cemetery in karroid veld along dry stream bed just off gravel road to Camphorspoort, elevation 613 m, 17 September 2011 in fruit, D. Cumming s.n. (photo!) ; ibidem, 5 August 2014 in flower, A. P. Dold 140021 ( GRA!) ; ibidem, 12 November 2014 in fruit, A. P. Dold 140024 ( GRA!) ; Eastern Cape, Steytlerville (3324): Teasdale farm, ca. 6.7 km south east of Klipplaat (- AB), 12 November 2014 in fruit, A. P. Dold 140023 ( GRA!) ; Eastern Cape, Steytlerville (3324): Monteaux Farm, 17.8 km east of Steytlerville on road to Cockscomb–Uitenhage (- BC) [not SE of Middleton, as given on iSpot], elevation 384 m, 33.43003ºS, 24.51642ºE, 13 August 2011 in flower and fruit, N. van Berkel s.n. (Photo!, iSpot: http:// www.ispot.org.za/node/131878) ; ibidem, 11 June 2014 vegetative, A. P. Dold (photo!) ; Eastern Cape, Somerset East (3325): Darlington Dam ( Lake Mentz ), roadside reserve on R400 (- AA), D. M. Cumming 11862 http://www.zelenelisty. cz/clanky/werbar---cibuloviny/massonia-depressa-v-ponekud-antidepresnim-provedeni.html (photo!) ; Western Cape, Ladismith (3321): Gamkaberg Nature Reserve, south of Calitzdorp (- DA), 33.6354ºS 21.6522ºE, elevation 287 m, 20 August 2014 in flower, C. Ralston s.n. (photo!, iSpot: http://www.ispot.org.za/node/282025) ; Western Cape, just outside Calitzdorp, 27 September 2006 in fruit, M. Heigan s.n. (photo!, https://www.flickr.com/photos/97303475@ N 00/2138602137) ; Western Cape, Caledon (3419): Hermanus coastline (- AC or - AD), 23 July 1965 in flower, F. Stayner s.n. ( NBG81957 !) ; Unknown locality, P. Knippels s.n. (photo! http://www.bloembol.info/nieuws_2010_n.html) .

Figures

FIGURE 3. Massonia obermeyerae Mart.-Azorín, A.P.Dold, M.Pinter & Wetschnig from Darlington Dam (Lake Mentz), Eastern Cape, South Africa (corresponding to D.M. Cumming 11862). a. Plant in flower; b. Inflorescence in apical view. Scale bars 1 cm.

FIGURE 4. Buds, flowers and bracts of Massonia obermeyerae Mart.-Azorín, A.P.Dold, M.Pinter & Wetschnig from Darlington Dam (Lake Mentz), Eastern Cape, South Africa (corresponding to D.M. Cumming 11862). a. Flowers before anthesis; b. Flowers at anthesis; c. Bracts and gynoecium in lateral view. Scale bar: 1 cm.

FIGURE 5. Massonia obermeyerae Mart.-Azorín, A.P.Dold, M.Pinter & Wetschnig from the wild at Klipplaat. a. Fruiting plant on 17 September 2011 (Photo D.M. Cumming); b. dehiscent capsule in lateral view on 13 November 2014. Scale bar 1 cm.

FIGURE 6. Seed morphology of Massonia obermeyerae Mart.-Azorín, A.P.Dold, M.Pinter & Wetschnig collected from the wild at Klipplaat. a. Seed, lateral view; b. Seed, raphal view; c. Seed, longitudinal section; d. Seed, transversal section. Scale bars: 0.5 mm.

FIGURE 7. Known distribution of Massonia obermeyerae Mart.-Azorín, A.P.Dold, M.Pinter & Wetschnig in South Africa. Type locality indicated by symbol with white centre.