A note on the Stachys aethiopica Complex

The Stachys aethiopica Complex is examined and a key provided to the species recognized. The com ­ bination S. natalensis Hochst. var. galpinii (Briq.) Codd is effected and two new species, S. reticulata Codd and S. arachnoidea Codd are described.

Among the South African species of Stachys one of the main taxonomic problems concerns the delimitation of species in the S. aethiopica Complex.These comprise mainly soft, nondescript, somewhat straggly perennial herbs with small ovate cordate leaves and relatively small, inconspicuous flowers.The complex extends from the south-western extremity of the Cape Province, through the eastern summerrainfall parts of southern Africa northwards into tropical Africa.
S. aethiopica L., Mant. 1: 82 (1767) was the first to be described and was presumably based on material from the south-western Cape Province.Further species have been distinguished on the basis of differences in tomentum, whether the leaves are petiolate or sessile, on the number of flowers per verticil and, to some extent, on leaf shape.
Most of these entities represent local variations of restricted extent which may or may not warrant the rank of species.Due to inadequate collecting, many of them are still very poorly known and a good deal more material is required before their status can be assessed.
In the present study the above 24 "species" are reduced to 11, while two additional species are described from the eastern Transvaal and Swaziland.In few cases are there clear-cut differences between species and it is often necessary to rely on a com bination of characters.
The picture which emerges is of two widespread and variable species, from which a number of segregate species have arisen or are in the process of developing.The two widespread "parent" species, which can usually be separated on the basis of pubescence, are: (1)5.aethiopica L., with a mainly southern distribution from the south-western Cape to Natal, Lesotho and the Orange Free State, with the lower surfaces of the leaves and calyces thinly tomentulose to hispid or densely glandular; (2) a more northerly species, to w'hich the name S. natalensis Hochst. is applied, extending from Natal to Swaziland, Transvaal and Rhodesia, with the lower surfaces of the leaves and calyces hispidvillous (sometimes only on the nerves) to densely villous (often obscuring the surface), and with scarcely any glands.
The two species meet in Natal, w'here a gradation in pubescence occurs.In this critical area, however, one can separate them on another character, the number of flowers per verticil.In S. natalensis the verticils are 2-flow'ered throughout its entire range; in S. aethiopica the verticils appear to be always 4-6-flowered in Natal, Lesotho and the Orange Free State.In the Cape occasional specimens, some of them rather depauperate, are found with 2 or 3 flow'ers per verticil, but these do not have villous pubescence and would not be confused with S. natalensis.In this way, the two species can be maintained as distinct and some of the confusion of the past concerning the limits of S. aethiopica can be clarified.
With regard to the number of flowers per verticil, it must be remembered that there are certain segregate species related to S. aethiopica which have 2-flowered verticils (S. rudatisii, S. cymbalaria and S. sublobata), in the same way that there are species with villous to densely tomentose pubescence related to S. natalensis but with 4-6-flowered verticils (S. milacophylla and the newly described S. reticulata).In other species the number of flowers per verticil is not constant and may very from 2-6 {S.rehmannii, S. scabrida and S. flexuosa).
From the foregoing it will be realized that the construction of a key that will work satisfactorily for every specimen is not an easy matter.The following key must, therefore, act mainly as a guide.With the increase in knowledge as further material comes in, it is quite likely that our species concepts will be modified.
A little-known species from southern Natal where it apparently grows in damp grassy places among rocks and in shady thickets.S. aethiopica (p.186) often has densely glandular stems and leaves but the leaves are usually smaller, broadly ovate and rather coarsely toothed, while the verticils are normally 4-6-flowered, not 2-flowered as in S. rudatisii.In the type, Rudatis 405, the bracts are large and leaf-like, while in Hilliard & Burtt 3488 the bracts are reduced, making it somewhat intermediate with 5. aethiopica.A specimen from the Hogsback, Rattray sub BOL 14275, may belong here, but the leaves are broadly ovate and subsessile.If the specimen were included here, the known area of the spesies would be extended considerably but more material, especially from the type area, is required before the limits of the species can be assessed.
Found in forest margins and on grassy slopes in the mountains of eastern Transvaal and northern Swaziland at altitudes of 1 300-2 000 m.Although first collected as early as 1905 by Bolus near Mbabane in Swaziland, this species has been confused with S. transvaalensis (now included in S. natalensis, p. 185) and S. rudatisii.It was listed under both these names by Compton, FI. Swaz. 66 (1966), but can be distinguished by the rounder, discolorous leaves with white cobwebby tomentum and minute yellow gland-dots on the lower surfaces.It shows no close relationship to any other species and is probably the most clear-cut member of the S. aethiopia complex.3. Stachys rehmannii Skan in FI.Cap. 5,1: 345 (1910).Type: Transvaal, Houtbosch, Rehmann 6178 (K, holo.!).
Found among rocks in mountain grassland at altitudes of 1 300-2 200 m in the northern and north-eastern Transvaal.Readily distinguished from all other members of the S. aethiopica complex by the presence of dense stellate pubescence on all parts of the plant.4. Stachys reticulata Codd, sp.nov., a S. aethiopica L. foliis discoloribus, subtus reticulatis dense tomentosis, dentibus calyce patentibus differt.
Type Although confused in the past with S. aethiopica, 5. reticulata may be distinguished by the usually discolorous leaves, reticulate and densely tomentose below, and by the spreading calyx teeth, The tomentum on the stems is also characteristic being fairly densely appressed pilose.The stem pubescence of S. aethipica varies from retrorse to antrorse or spreading, but is usually short and hispid.
From S. natalensis it differs in the 4-6-flowered verticils, the reticulate venation on the undersides of the leaves and in the spreading calyx teeth, while from S. rehmannii it can readily be separated by the simple, not stellate, pubescence.
It was first collected on the exposed summits of hills near Pilgrims Rest by Galpin in 1937 and appears to be restricted to the mountains of the Pilgrims Rest District, where it usually grows among rocks of the Black Reef quartzite formation.Stem fairly densely spreading-pilose.Leaves petiolate, blade broadly ovate, l,4-3x 1-2,2 cm, densely appressed pilose above, matted velvety pilose below.Bracts differentiated from the leaves.Verticils usually 4-6-flowered but sometimes 2-or 3-flowered.Calyx densely hispid-villous.
A little-known species from mountains in the eastern Cape Province.Closely related to S. sessilifolia from which it is separated by the petiolate leaves and usually 4-6flowered verticils, while the tomentum on the stems and leaves is less densely woolly.Both species are very poorly known and further collecting is required in order to establish how reliable these distinctions are.See also notes under S. reticulata from the eastern Transvaal.
Found in dense grassland in the eastern Cape Province.A little-known species closely related to S. natalensis and which may be only an extreme form of that species, distinguished by the densely matted-villous lower surface of the leaves.Further material is required in order to determine how meaningful this distinction is.
A specimen from northern Natal, Grid 2730 (Vryheid): near Luneburg (-BC), Galpin 9870, has this type of tomentum and 2-flowered verticils but differs in having petioles up to 7 mm long.It is tentatively included in S. sessilifolia until more material is forthcoming in order to assess the importance of subsessile versus petiolate leaves.It may be noted that this character varies a good deal in the material included in S. natalensis below.
The type of S. bachmannii has not been seen; the species was included in S. sessilifolia by Skan and, judging by its description, this decision appears to be correct.
Stems variously pubescent from densely to sparingly villous or shortly scabrid to softly pubescent.Leaves subsessile or petiolate; blade ovate to ovate-deltoid, variable in size, 1-4x0,6-2,4 cm shortly and sparingly appressed pubescent to densely strigose above, less dense, more spreading and mainly on the nerves below often with some glandular hairs but not conspicuously glandular.Bracts differentiated towards the apex.Verticils 2-flowered.Calyx densely villous to densely and shortly pubescent, usually without glands.
A widespread and variable species found in grass on stony hillsides, in semi-shady kloofs and wooded places in the mountains of northern central and eastern Transvaal, Swaziland, northern and coastal Natal as far south as Durban, with an occasional record from the eastern Cape.Also recorded from Rhodesia.
No material of the type, Krauss 1139 from Table Mt., near Pietermaritzburg, has been traced, but the description is considered adequate to identify it with the present concept, though Skan, I.e., lists it as an "imperfectly known species."The specimen Schlechter 2894 from near Verulam, Natal, may be regarded as representative and, if no material of the type can be found, would be a suitable specimen to select as a lectotype.
Two varieties, based mainly on the degree of pubescence, are recognized.Stems shortly scabrid or tomentose to sparingly or fairly densely villous.Leaves petiolate, blade hispidvillous above, less so and mainly on the nerves below.Calyx hispid-villous.

Key to varieties
Distribution and ecology more or less as for the species but not prevalent in the mountain grassland of the eastern Transvaal.Also occurs in Rhodesia.
In general the pubescence is sparingly to fairly densely villous and grades somewhat into the very densely villous pubescence of var.galpinii.In Natal some specimens have hispid or shortly tomentose pubescence, resembling the condition often found in S', aethiopica, but may be separated from that species by the 2-flowered verticils.The type of S. leptoclada Briq., Schlechter 6865 (Z) from Bloukrans River near Ladysmith is such a plant.Schlechter 6865 may be a mixed gathering because the specimen in PRE with this number is S. grandifolia E. Mey.ex Benth.or, more likely, the material may have become mixed when it was distributed.The type of S. transvaalensis Guerke is more densely pubescent than typical var.natalensis.
(b) var.galpinii (Briq.)Codd, stat.nov.This variety can be recognized by the combination of densely villous pubescence and 2-flowered verticils; it grades into var.natalensis and many specimens may be regarded as transitional between the two.In var.galpinii the leaves may be petiolate or subsessile and the latter specimens come near to S. sessilifolia, in which the lower surfaces of the leaves are densely matted-villous and the stems are softly tomentose.In S. malacophylla the lower surfaces of the leaves are also densely pubescent, but the verticils are usually 6-flowered.The types of S. lupulina Briq., S. parilis N.E.Br. and S. villosissima H. M. Forbes are not appreciably distinct from that of S. galpinii.
Skan, I.e., draws attention to the confusion concerning the type of S. lupulina.Briquet cites the specimen as "Natal, Claremontplats prope Claremont, Schlechter 4651, ann.1892."On the type sheet in Z and an isotype in BOL the label reads: "Claremont flats prope Cape Town, Schlechter 465, 9. III.1892".It is undoubtedly conspecific with S. natalensis var.galpinii, which does not occur in the Cape, but could have been collected in northern Natal or the eastern Transvaal.Skan concluded that it had probably been introduced at the Cape but there is no evidence to support this.
Distributed from Clanwilliam District to the Peninsula and along the coast to the eastern Cape Province and to Natal, Lesotho and the Orange Free State; found in a variety of habitats from fynbos to dry woodland and coastal dune bush, extending to mountain grassland where it is usually found among sandstone rocks.
Skan attempted to reduce the confusion which existed in this complex by isolating certain discordant elements as separate species, and by upholding four varieties within S. aethiopica.With the advent of a good deal of modern material, the position is still confused, but it appears that a broader concept of the species should be adopted, while the separation of varieties within S. aethiopica seems scarcely justified.
Several of the peripheral species upheld by Skan are still maintained, such as S. rudatisii, S. graciliflora (= S .cooperi), S. scabrida (=S.priorii), S. flexuosa, S. cymbalaria and S. sublobata, and the distinguishing characters are discussed under the respective headings.Others, such as S. harveyi, S. serrulata, S. attenuata and S. fruticetorum are now included in S. aethiopica.
Regarding the typification of S. aethiopica, Linnaeus refers to Pluk., Aim.245, t. 315, f. 3, while the description indicates that he had a specimen before him.Of these two elements, the specimen in the Linnaean Herbarium No. 736.13 may be regarded as the type and is a plant with retrorse to spreading pubescence and lacking glandular hairs.In both elements the plant referred to has 2-flowered verticils, but this must be regarded as exceptional as most specimens which match the type have 2-6-flowered verticils.The typical form occurs mainly in the south-western Cape Province, but it grades into the varieties upheld by Skan.
Bentham based his var.hispidissima on a Drege gathering with denser and more stiffly spreading hairs on stems and leaves, but this is scarcely distinct from the typical form.The other two varieties, described by Skan, are possibly more distinct but, due to the many intermediates, it is preferred to regard them as forms rather than give them taxonomic rank.
In the plants placed by Skan in var.parviflora, the hairs on the stem are antrorse and shortly scabrid, the petioles tend to be shorter and the flowers smaller.Salter in FI.Cape Penins. 697 (1950) upheld this variety but, as one moves away from the Peninsula, the distinction becomes less clear.
The form separated as var.glandulifera is usually recognizable under magnification by the glandularpuberulous pubescence on most parts of the plants, especially the under-surface of the leaf, the rhachis and the calyx.It appears to be the prevalent form in the eastern, summer-rainfall part of South Africa, especially along the Drakensberg escarpment.Towards the west it grades into typical S. aethiopica and the type of S. fruticetorum, Schlechter 1179 from Sir Lowry's Pass, is an intermediate specimen.
Another form has been observed along the coast of Natal in which the leaves are much larger than usual, up to 6x 4 cm.It appears to be a semi-weed in disturbed areas, and serious consideration was given to according it separate status of some sort.
However, there is a gradation in leaf size and many intermediate specimens cannot be allocated with certainty.At present it is regarded as a form growing under favourable subtropical conditions.The pubescence is somewhat similar to the plants discussed under var.glandulifera.
To summarize, the pubescence in S. aethiopica is mainly hispid, either antrorse, retrorse or spreading, sometimes with scattered longish hairs and often finely glandular, especially on the calyx and under surface of the leaves.This can usually be distinguished from the villous pubescence of S. natalensis but there should be no confusion between the two because, in the eastern summer-rainfall areas, S. aethiopica always has 4-6-flowered verticils, while S. natalensis is strictly 2-flowered.The two overlap in Natal and the extreme eastern Cape Province.S. aethiopica is absent from the Transvaal and rare in Swaziland, but a very glandular form occurs in Lesotho and the eastern Orange Free State.
As it often happens in variable species, S. aethiopica tends to be a repository for specimens which cannot satisfactorily be placed elsewhere.For example, a few specimens of rather distinct facies, with stiff stems and very densely glandular-puberulous stems, leaves and calyces, but with 2-flowered verticils, have been collected in the eastern Cape Province, namely: Stutterheim District, Acocks 2971 and Sim s.n.; Port St. Johns District, Flanagan 2595.If S. aethiopica were divided into formal varieties, these specimens would probably be worthy of varietal rank.

S. cooperi
A soft straggling herb of moist places in forest margins, in grass, fynbos or coastal scarub from southern Natal to Knysna in the Cape.There is a gradation in leaf size from the specimens with larger and softer leaves, described as S. cooperi Skan, to those occurring further west with smaller and firmer leaves, w hich match the type of S. gracili flora Presl.The stem pubescence of the latter tends to be slightly more scabrid and thus approaches the condition found in S. scabrida Skan (see below).However in S. scabrida the leaves are somewhat thicker in texture, dry dark brown and the hairs on the upper leaf surface are thicker with distinctly swollen bases.On these grounds S. scabrida is kept distinct, but the two overlap from southern Transkei to Knysna and further study in this area is required.
As mentioned under the previous species, S. aethiopica sometimes has few, fairly condensed verticils which resemble those of S. graciliflora.However, these plants usually have a coarser pubescence on the stems, while gland-dots are often present on the calyx and on the lower surface of the leaves.No glandular hairs are found in S. graciliflora.
Specimens with large leaves resemble S. tubulosa MacOwan, a species not included in the present treatment, but may be separated, when flowers are available, by the shorter corolla tube which does not exceed 10 mm in length.In 5. tubulosa the corolla tube is 12-18 mm long and the species has a more northerly distribution from East Griqualand to Swaziland.

S. priorii
A straggling herb in grass, fynbos or coastal scrub, extending from the southern Transkei to Knysna and, inland, to Steynsburg and Somerset East Districts.S. scabrida appears to be related to S. graciliflora, but the pubescence is coarser and more scabrid, while the leaves are thicker-textured and the hairs on the upper leaf surface tend to be bulbous-based.The inflorescences tend to be more slender, rather Stems slender, wiry, subglabrous or with a few long slender spreading hairs or occasionally shortly glandular-pubescent.Leaves petiolate, blade small, broadly ovate-deltoid to suborbicular, 8-15x6-12 mm, subglabrous to thinly appressed-pubescent or glandular-puberulous. Inflorescence lax of 1-5 verticils; verticils 2-flowered; bracts differentiated, the upper shorter than the calyx.Calyx puberulous to hispidulous.
Found among rocks in exposed mountain grassland, at altitudes of 1 000-1 800 m; recorded from a few disjunct localities in southern Natal and the eastern Cape Province.The species is closely related to S. aethiopica but is characterized by the many wiry stems radiating from the apex of a slender taproot, the small ovate to roundish leaves and the 2-flowered verticils.
Found on hillsides in fynbos at altitudes of 300-900 m in the south-western Cape Province; known from a few localities between Caledon and Mossel Bay and, inland, to Ladismith and Oudtshoorn Districts.This species resembles S. cymbalaria and, like that species, is closely related to S. aethiopica, but can be recognized by the narrowly triangular leaves, rather thickish in texture and with deeply crenate, almost lobed margins.It normally has 2-flowered verticils, but one portion of Galpin 4426 in PRE, which matches S. sublobata, has 6-flowered verticils.The other specimen mounted on the same sheet has larger leaves and is S. aethiopica.
Known from a few localities in the eastern Cape Province, among rocks in mountain grassland.The species is included here because the small ovate leaves with a rather wide sinus at the base are reminiscent of the S. aethiopica complex, but the relationship appears to be with another complex which includes S. obtusifolia and S. tysonii.From these it differs mainly in the smaller leaves, and less densely villous stems and leaves, in contrast to the markedly glandular pubescence of S. tysonii.As in many other species of Stachys, a good deal more material is required before the status of S. fiexuosa can be reliably determined.