Haworthia Revisited – 51. Haworthia nigra

51. Haworthia nigra (Haw.) Baker, J.Linn.Soc.Bot. 18:203(1880).  V.Poelln., Feddes Repert.Spec.Nov. 44:209(1938).  Ibid., Kakt.u.a.Sukk. 10:170(1937).  Bayer :140(1976).  Bayer :70(1982).  Scott :29(1985).  Apicra nigra Haw., Phil.Mag.46:302(1825).  Type: Cape, Bowie.  Not preserved.  Lectotype (See Scott 1985): icon (K).  Epitype (ex B&M): Campherpoort, Barker 5099 (NBG):  H. schmidtiana V.Poelln., Feddes Repert.Spec.Nov. 26:23(1929).  ibid. 41:210(1937).  ibid., Kakt.u.a.Sukk. 10:170(1937).  ibid.  Feddes Repert.Spec.Nov., 44:205(1938).  H. nigra var. schmidtiana (V.Poelln.) Uitew., Succulenta :51(1948).  Type: Cape, imported.  Not preserved:  H. schmidtiana var. angustata V.Poelln., Kakt.u.a.Sukk. 10:169(1937).  ibid., Feddes Repert.Spec.Nov. 44:205(1938).  H. nigra var. angustata (V.Poelln.) Uitew. loc.cit.  Type: Cape, Ladismith, Mr Joubert in Triebn. 817.  Not preserved:  H. schmidtiana var. suberecta V.Poelln., Kakt.u.a.Sukk. 10:169(1937).  ibid., Feddes Repert.Spec.Nov. 44:205(1938).  H. nigra var. suberecta (V.Poelln.) Uitew. loc.cit.  Type: Cape, 24km W. East London, Kluth in Triebn. 920.  Not preserved:  H. schmidtiana var. pusilla V.Poelln., Feddes Repert.Spec.Nov. 44:240(1938).  H. nigra var. pusilla (V.Poelln.) Uitew. loc.cit.  Type: Cape, Aberdeen, Wilke in Triebn.1152.  Not preserved:  H. ryneveldii V.Poelln., Des.Pl.Life 5:88(1939).  ibid., Feddes Repert.Spec.Nov. 46:271(1939).  Type: Cape, Somerset East Armstrong.  Not preserved.

nigra: black.

Rosette usually caulescent, slowly proliferous or often stoloniferous, to 50mm tall, occasionally taller.  Leaves to 30 X 15mm, ovate-deltoid, erect or recurved-spreading, blackish to grey-green, opaque, surfaces scabrid with distinct raised non-confluent concolorous tubercles.  Inflorescence simple, lax.  Flowers erect, tepals fused, tube straight, inner lower tepals revolute.

1982 – It is not surprising that Haworth thought this species to be an Astroloba (Apicra).  The close trifarious arrangement of the leaves of particularly the northwestern forms of H. nigra however, led von Poellnitz to ignore the obvious synonymy.  Astroloba aspera (Willd.) Uitew. was originally described as trifarious and Mrs Roberts‑Reinecke (unpublished thesis, University of Cape Town) is probably correct in suggesting that this is actually an Haworthia.  H. nigra was described by Haworth as multifarious but it is apparent from many collections that the leaf tiers may vary from an obvious 3‑tiered arrangement to an indistinct multifarious one.  Similarly plants may also be comparatively stemless.  The distribution is from near East London in the southeast to north of Loeriesfontein in the northwest.  H. nigra is characterised by its very dark colour and the many flattened tubercles on the leaf surfaces.  It may propagate stoloniferously or from offsets, as does H. venosa ssp. tessellata, to which it may be closest related.

1999 – This is a prime example of the need for good records and herbarium specimens.  The only good evidence of Haworth’s original species is the Kew illustration, and this is not enough to show what the species can actually do.  Von Poellnitz landed himself in a real predicament.  It is possible on the evidence in this species (and contrary to my comment in the historical sketch) that had he lived longer he could have ended up completely stranded.  As more material comes in, so does the problem get more complex.  It is still not certain what H. aspera of Haworth might have been, and probably an argument could be made for priority over H. nigra.  There is a contemporaneous name, H. nigricans Haw., which would have page priority and which could equally apply.  The position simply is that here we have a discrete element which is very widespread and which is as variable as we all should have come to expect in the genus.  The leaves may be tightly in three erect tiers or the tiers may spiral.  The leaves may be recurved and elongated away from the stem, or short and compressed upon one another.  The plants may have very long elongated stems or be reduced to almost stemlessness.  The colour may vary from very dark green and almost black, to light grey.  The variability in the species may best be expressed as follows:-


a. var. nigra.
The typical form of the species is represented by the Kew illustration which is of a virtually stemless plant.  This represents the eastern forms with shorter stems; the leaf colour is blackish-green and the leaves are slightly loosely arranged on the stems and not obviously in three vertical tiers.  The leaves are recurved to greater or lesser degree and the tubercles are concolorous and non-confluent in longitudinal rows.

Distribution: 3124(Hanover): Krugerskraal (-CD), Branch 316 (NBG).  3125((Middelburg): Thebus (-BC), Smith 3097 (NBG); NW. Cradock (-CD), Smith 5792 (NBG).  3126(Queenstown): Goedemoed (-CA), Branch 24 (NBG); Tarkastad (-CD), Pringle (NBG); SW. Queenstown (-DC), Smith 5197 (NBG); Bowkers Kop (-DD), Smith 6824 (NBG); Finchams Nek (-DD), Smith 7213 (NBG).  3127(Molteno): Cofimvaba (-CD), Bruyns 4384 (BOL).  3223(Rietbron): 25km S. of Aberdeen (-DB), Acocks 19901 (PRE).  3224(Graaff Reinett): St Olives (-AB), Bayer 2350 (NBG); Riverdale (-BA), Bruyns 1756b (NBG); Goliadskraal (-BA), Fourcade 138 (NBG); Tandjiesberg (-BC), Bruyns 2971 (NBG); Marais Siding (-CB), Bruyns 2964 (BOL); Stoepie Stn. (-CD), Rossouw 192 (NBG); 26km SW. of Pearston (-DB), Acocks 11987 (PRE).  3225(Somerset East): Lake Mentz (-AA), Smith 3522 (NBG); Rooiplaat (-AB), Branch 32 (NBG); Swagershoek (-AD), James (BOL); Halesowen (-BB), Smith 2291, 5338 (NBG); Mortimer (-BC), Kensit (BOL): Waterdown Dam (-BD), Bayer & Bruyns 6568 (NBG); E. Cookhouse (-DB), Fourcade 84 (NBG); 3km E. Cookhouse (DB), Long 1029 (PRE); Eastpoort (-DB), Smith 3490 (NBG).  3226(Fort Beaufort): Bedford (-AC), Pringle (NBG); Adelaide (-CB), Bayer & Bruyns 6575 (NBG); Middeldrift (-DD), Immelman in NBG1883/28.  3227(Kingwilliamstown): N. Waku (-AA), Smith 5717, 5717a (NBG); Waku (-AA), Pillans 849 (BOL); NW. Cathcart (-AA), Smith 3632 (NBG); Tylden (-AA), Smith 359 (NBG); Goshen (-AC), Branch 21 (NBG); Tsomo (-BB), Branch 14 (NBG).  3322(Oudtshoorn): Sleutelfontein (-AB), Bruyns 2610 (NBG).  3324(Steytlerville): Campherspoort (‑AA), Barker 5099 (NBG), Smith 7060 (NBG); E. Twowaters (-BC), Smith 2917 (NBG); Kleinpoort (-BD), Smith 7064 (NBG).  3326(Grahamstown): Hetherton Tower, Smith 1985 (NBG); The Fort (-BA), Smith 5062 (NBG); Fort Brown (-BA), Smith 3841, 3863 (NBG); N. Trumpeters Drift (-BA), Smith 5414 (NBG); Committees (-BB), Smith 2247, 3187, 5412, 5413, 5415, 7443 (NBG).  3327(East London): E. Hunts Drift (-AC), Smith 5655 (NBG).

Inadequately located: Somerset East, Smith 2397 (NBG); Queenstown, Smith 6166 (NBG); Cradock, Smith 7369, 7370 (NBG); ex hort Smith 1146, 2812, 2821, 2829 (NBG); ex hort Whitehill NBG68247.


b. var. elongata (V.Poelln.) Uitew., Succulenta :51(1948). H. schmidtiana var. elongata V.Poelln., Feddes Repert.Spec.Nov. 44:240(1938).  Type: Cape, Bulkraal, Slagtersnek, Daly.  Not preserved.  Neotype (designated here): CAPE-3225(Somerset East): Slagtersnek (-DB), Van Jaarsveld & Marthinus 7913 (NBG).

This variant may be more generally distributed than is presently known.  It is characterised only by the very great length that the stems may attain, upto 400mm.

Distribution: 3225(Somerset East): Slagtersnek (-DB), Van Jaarsveld & Marthinus 7913 (NBG).


c. var. diversifolia (V.Poelln.) Uitew., Succulenta :51(1948).  H. diversifolia V.Poelln. loc.cit. 41:200(1937).  H. schmidtiana var. diversifolia idem. 44:205(1938).  Type: Cape, Prieska, Draghoender, Mrs van der Bijl in Triebn. 818.  Not preserved.  Neotype (designated here): CAPE-3323(Willowmore): Kruidfontein (-AB), Bruyns in KG435/75 (NBG):  H. schmidtiana var. diversifolia forma nana V.Poelln., Feddes Repert.Spec.Nov. 44:240(1938).  H. nigra var. diversifolia forma nana (V.Poelln.) Uitew. loc.cit.  Type: Cape, Beaufort West, Marais in Triebn.1078.  Not preserved.

The leaves are greyer-green and the tubercles still lighter and often confluent in transverse bands.  The leaves are tightly arranged on the stem.  Because they are short and only slightly recurved at the tips, their arrangement in three vertical tiers is very obvious.

Distribution: 3221(Fraserburg): Wilgerboskloof, Letskraal (-BB), Shearing 913 (PRE); Spitzkop (-CB), Bruyns 4863 (NBG); W. Merweville (-CB), Bayer 2469a (NBG); Klipfontein (-CC), Bruyns 3105 (NBG); SW. Klipfontein (-CC), Bruyns 3097 (NBG).  3222(Beaufort West): Wolwehoek (-AC), Bayer 4294 (NBG); Doornhoek (-AD), Bruyns 3993 (BOL); Lammertjiesleegte (-BC), Branch 293 (NBG); Prutkraal (-DD), Bruyns 3195 (NBG).  3323(Willowmore): Kruidfontein (-AB), Bruyns in KG435/75 (NBG); Miller (-BB), Pretorius in NBG68253 (NBG).