New and overlooked Acanthaceae taxa from the Democratic Republic of Congo (2): the genus Justicia

Results – Eleven new species are recognized; illustrations and distribution maps are provided. One overlooked species is discussed. The pollen of five species was investigated to allow their placement in the classification of Graham.


INTRODUCTION
During the revision of the Acanthaceae for the Flore d'Afrique centrale, we found in the unidentified material of BR about forty new species, two new subspecies and one new variety in various genera (Champluvier 2011).This second contribution concerns the genus Justicia.
Eleven new species are presented; cases of vicariance are highlighted; an additional record concerns a recently published species, J. scutifera Champl.All the new species are illustrated.Attention is also drawn to one hitherto overlooked species.Partial keys are composed to compare closely allied or morphologically similar species.Extensive descriptions for each taxon and their distribution maps are given.
The genus Justicia, comprising about 600-700 species (Darbyshire et al. 2010), is characterized mainly by its bilabiate corolla, its two stamens bearing bithecous anthers with usually superposed thecae, the lower theca provided with a white membranous basal appendage or spur, its stipitate capsule containing 2-4 usually ornamented seeds and its subprolate to perprolate, bi-or tricolporate pollen grains.Graham (1988) published an attempt to an infrageneric classification of Justicia, mainly based on the pollen characters and those of the corollas, inflorescences and seeds.We have placed every of the cited species in her classification, which is the more recent treatment available for Justicia, although the validity of some sections of Graham seems to be doubtful (Darbyshire et al. 2010).To do so, pollen of five new species was investigated here.

Justicia and the closely allied genera
In the recently published volume 2 of Acanthaceae for Flora of Tropical East Africa (FTEA 2010), Monechma and Rungia are merged into Justicia.However, preliminary published and current unpublished DNA studies performed in Rancho Santa Ana Botanical Garden, California, by Lucinda Mc Dade and her staff do not speak for that position (Mc Dade, pers. comm.).Nevertheless, it seems preferable, for practical reasons and for an homogeneous treatment of the family in all the tropical African recent Floras, to adopt in the Flore d'Afrique Centrale the position of the authors of the family in FTEA, i.e. to merge Monechma and Rungia into Justicia.Morphologically, indeed, it is difficult to find good characters to separate those genera from Justicia.Among the closest relatives of Justicia in tropical Africa are the genera Isoglossa, Dicliptera and Hypoestes.Isoglossa is easily separated by its stamens bearing usually two clearly distant muticous thecae and by its lenticular pollen grains showing a thick exine margin.Dicliptera and Hypoestes, the first with anthers bearing also two clearly distant muticous thecae, the second with monothecous anthers, are also distinct by the corolla tube which is twisted through 180° and by inflorescences composed of monochasial cymules usually surrounded by two paired opposite bracts.

Taxonomy of Justicia and position of the new described species
In Justicia, mainly as in other genera of Acanthaceae, the most important diagnostic characters are found in the type of inflorescence and in the shape, colour and size of the corolla and bracts and in the features of the stamens and pollen grains.Graham (1988), in her attempt at an infrageneric classification of Justicia, underscores the pollen type and the shape and colour of the corolla as valuable taxonomic characters at the sectional level within the genus: for instance, cucullate upper lip is characteristic of several sections in the genus; three sections (Vasica, Rhaphidospora and Justi cia) have greenish purple-marked, cream or white flowers, whereas sect.Tyloglossa only shows yellow or purple corollas.
The ornamentation of the seeds is also valuable in taxonomic distinctions (Graham 1988), but seeds are not always available on the collected specimens.
The relationships between the new species and the rest of the genus are partly underscored in the Latin diagnosis, when the new species is compared with the closest one or with a group of species of the genus, but sometimes, this likeness can be superficial and does not reflect the true relationship of the new species.An analysis of pollen, alongside with inflorescence's and corolla's characters is probably the best way to assess it.
A pollen analysis has been performed for the five species (four new ones and an overlooked one) of which the relationships cannot be assessed surely from the morphological characters of the plant.
The pollen of four species, Justicia gladiatotheca, J. len ticellata, J. pedemontana and the overlooked J. bequaertii (figs 1-4) matches the 'type 1' pollen of Graham (1988), i.e. a triporate pollen grain with one raised band of exine and one pseudocolpus on each side of the pore.This type of pollen is characteristic of three sections of Justicia, two of which being represented in Africa, sect.Betonica and sect.Rhaphi dospora.sect.Betonica includes species with simple spikes    Champluvier, New and overlooked Justicia spp.(Acanthaceae) from D.R.Congo and conspicuous, ovate-elliptic bracts; this matches well the characters of J. gladiatotheca.
J. lenticellata and J. bequaertii, having inconspicuous bracts subtending several flowers (at least at some nodes) and white or whitish corollas, better match sect.Rhaphidos pora.J. pedemontana has also the pollen and inflorescence matching that section, but has obovate conspicuous bracts not encountered in the section, except in J. ventricosa, an Asian species considered by Graham as peripheral to the section Rhaphidospora; J. pedemontana could perhaps be similarly regarded as peripheral to that group.
The fifth species, J. nanofrutex, possesses the 'type 5' pollen of Graham, i.e. a biporate pollen grain with the trema area traversed by two rows of 3-6 insulae (fig.5F).This pollen type characterizes three sections represented in Africa, sect.Vasica, sect.Harnieria and sect.Rostellaria.The section Vasica seems the most appropriate to include J. na nofrutex as all the species of the section are simple-spiked, shrubby perennials and have mostly large corollas, characters shown by J. nanofrutex; all the species have ovate bracts except one which has narrowly elliptic bracts; J. nanofrutex possesses narrowly lanceolate-elliptic bracts.Unusual characters like the presence of a second partial row of insulae on each side of the pore and flowers white flushed with mauve opposed to white or cream corollas in the rest of the section could give J. nanofrutex a marginal position in the sect.Va sica, situation that occurs elsewhere for other species in the classification of Graham.
The relationship of the remaining species is easier to assess using Graham's work, where almost all the known species of Justicia are classified: J. tutukuensis, close to J. biokoensis, and J. catenula, (of which the pollen was not studied because the scarcity of the collections), very similar to J. interrupta, must belong to the sect.Rhaphidospora: this section encompasses mainly shrubby perennials, having a simple or compound dichasial inflorescence -if simple, without conspicuous bracts, and if compound, with conspicuous subulate or ovate bracts shorter to longer than the calyx, with white or cream to yellowish, more rarely pale pink or purple, often purple spotted corolla 9-45 mm long, with a 'type 1' pollen.J. abscondita, close to J. unyorensis, belongs to the sect.Harnieria.This section comprises shrubby or herbaceous, sometimes annual plants with axillary clusters of flowers, a corolla very rarely exceeding 2.5 cm long, often much shorter, with a 'type 5' pollen.J. alchorneeticola, close to J. betonica, belongs to the sect.Betonica, this section being characterized by an inflorescence consisting in a simple spike, with conspicuous ovate to oblanceolate bracts usually exceeding the calyx and imbricate, and a white or mauve to blue corolla, the pollen belonging to the 'type 1'.Sarmentous woody climber up to 6 m high; stem with orange-brown or red-brown bark.Lamina of the leaves elliptic, 6-20 × 2.3-10.5 cm, widely cuneate to rounded at the base, shortly acuminate at the tip, sparsely pubescent above, pubescent on the nerves beneath, median nerve prominent below, 4-12 pairs of lateral nerves; petiole 1.5-6.5 cm long.Inflorescence a spreading short to long panicle 7-23 cm long, up to 10(-14) cm wide, with visible axes; bracts linearlanceolate, 1-1.5 cm long on the main axis, 0.5 cm long on branchlets; calyx 14 mm long, lobes linear, densely covered with straight glandular hairs on both sides, 12 mm long; corolla 3-4.5 cm long, provided outside with straight glandular hairs; tube very short in relation to the lips, 1.2-1.8cm long with the cylindric part 0.75-1.1 cm long, and with the throat 1.2-1.8cm wide; upper lip green, spotted with red-violet and lower lip white-rose, spotted with violet or corolla white striate with violet; upper lip hooded and longitudinally folded, oblong, shortly bilobed at the tip, 25 × 6 mm; lower lip 22 × 23 mm, trilobed, median lobe 12 × 5 mm, lateral ones 12 × 7 mm; filament of the stamens glabrous, 3 cm long, anthers 6 mm long, thecae slightly distant from each other (all measurements given after those of the tube are taken from a corolla 4 cm long); ovary 2 mm, hirsute; style puberulentglandular, 4 cm long.Capsule densely pubescent and glandular, 32 mm long.Seeds tuberculate, 4 mm in diameter.Fig. 6.Distribution -A species of the Guineo-Congolian centre of endemism, only known so far from the Congo Basin, D.R.Congo.Fig. 7. Habitat -Riparian forests.

Justicia tutukuensis
Remark -This species shows the same distribution as Bridelia ripicola (Euphorbiaceae) and Sorindeia ripicola (Ana cardiaceae), which are strictly limited to the banks of the Congo river and its larger tributaries -a pattern discussed by Léonard (1990) and Champluvier (1999).Those riparian species are always closely related to terra firma species and only differ from them by small but correlated and constant characters, for instance Bridelia ripicola and B. micrantha, Sorindeia ripicola and S. juglandifolia, Justicia tutukuensis and J. claessensii, Justicia alchorneeticola and J. betonica (see further).They can be considered as ecological vicariants.Small suffrutescent plant up to 25 cm high with pubescent stems and a thin rootstock.Lamina of the leaves small, 1.4-3 × 1-1.8 cm, ovate-elliptic, cuneate to attenuate at the base, obtuse to rounded at the tip, roughly pubescent, shortly petiolate to subsessile; petiole up to 3 mm long.Inflorescence a spike, rather dense, 3.5-6.5 cm long; bracts not imbricate, elliptic, green, puberulent, subacute to subrounded at the tip, 5-7 × 2-4 mm; bracteoles oblong, 5 × 2.5 mm; calyx 4 mm long, with five triangular lobes 3 × 1.5 mm, acute at the tip; corolla white or cream, infundibuliform, 12 mm long and 4 mm wide at the throat, puberulent outside; tube 6 mm long, inside with two rows of hairs below the stamens and the folds of the rugula hairy at the base; upper lip ovate-triangular, 6 × 5 mm, bilobed at the tip, lower lip obtrapezoidal, 6 × 8 mm at the tip, trilobed, lateral lobes oblong, 5 × 2 mm, median lobe ovate-oblong, 4 × 3.5 mm; filament of the stamens glabrous, 4 mm long; thecae inserted at different levels, 1.25 mm long, slightly hairy on the back, the lower one with a 1 mm long acute spur at the base; ovary glabrous except on the two narrower sides, 1.75 mm long; style 7 mm long, hairy on the lower 2/3 of its length.Capsule 10 × 4-5 mm, shortly stipitate, puberulent.Seeds tuberculate, dark brown, about 3 mm in diameter.Habitat -Damp savannas, marshes.Remark -By its habit, J. gladiatotheca looks similar, at first sight, although being smaller, to J. ruwenzoriensis, reason why it is compared to that species in the Latin diagnosis but they seem actually not closely allied.J. gladiatotheca differs mainly by its spike bearing nonimbricate, elliptic, green and not nerved nor convex bracts; moreover, its slender roots are very different from the thick woody rootstock of J. ruwenzoriensis.Suffrutescent plant up to 1 m high, with a thick woody rootstock; stems glabrous.Lamina of the leaves ovate to elliptic, 6.5-20 × 3.2-8.5 cm, cuneate to attenuate at base, acuminate at the tip, glabrous, strongly bicoloured, green above, light grey-blue-green below; 6-8 pairs of main lateral nerves; petiole 4-20 mm long.Inflorescence a very poorly branched panicle composed of interrupted spikes with two flowers at each node or more rarely each node with two short peduncles each bearing up to three flowers, the terminal spike very variable in size, up to 32 cm long; axis glabrous or shortly puberulent or very sparsely pubescent; bracts inconspicuous; calyx 2-3 mm long, glabrous to sparsely puberulent and very slightly glandular; corolla 7-8 mm long, yellow to pink, densely puberulent and glandular outside; tube glabrous inside, 4 mm long, 3 mm wide at throat; upper lip ovate, 4 × 3.5 mm, lower lip 4 × 4 mm, trilobed, median lobe 1.5 × 1.75 mm, lateral ones 1 × 1 mm; filament of the stamens 3 mm long, glabrous except at the insertion on the corolla tube; thecae inserted one above the other, 1 mm long,  the lower one with an acute spur; style 5 mm long, hairy at the base; ovary 1.5 mm long, puberulent and glandular at the tip; disc annular, 0.5 mm high.Capsule 16 mm long, stipitate, densely puberulent and glandular, the swollen fertile upper part 4 mm wide.Fig. 10.Distribution -A linking species between the Guineo-Congolian/Zambezian regional transition zone and the Zambezian centre of endemism, only known so far from Kasai and Katanga, D.R.Congo.Fig. 7. Habitat -On alluvial deposits of riverbeds in gallery forests.Remark -Lindau (1897) described Duvernoia haplosta chya, based on a specimen collected by Descamps in June 1895 at Mtowa, Katanga.The isotype, a very poor specimen, is kept in BR.The species is recorded by Clarke (1900: 223) as an imperfectly known species, which probably indicates that the holotype, later destroyed in Berlin, was not a better specimen than the isotype.Indeed, the BR specimen, although resembling in habit to our species Justicia catenula, lacks flowers and shows a damaged poorly developed inflorescence bearing only a very young capsule.This is not enough for recognizing a well defined species, so it seemed preferable to describe a new species, Justicia catenula.In any case, Duvernoia having been merged into Justicia (Graham 1988: 584), and the name Justicia haplostachya being preoccupying as it was given in 1864 to a species from Madagascar by T. Anderson, a new name has to be chosen for the species of Lindau.Duvernoia haplostachya will consequently be considered as an imperfectly known species in the Flore d'Afrique Centrale.

Justicia catenula
Justicia interrupta, on its hand, although looking very similar to J. catenula, is more robust in all its parts and well separated from the latter by several good characters; moreover, it is strictly restricted to Tanzania, where it grows in evergreen and semi-evergreen forests, but also in riverine forests.The two species can then be considered as vicariants.
Speciebus Tyloglossae sectioni habitu similis, sed propter spicas longiores, bracteas obovatas nec ovatas nec lanceolatas nec lineares pilis moniliformis non munitas, corollae labium inferiorem magis profunde incisum cum lobis valde longioribus, capsulas majores seminaque tuberculata nec ammonitis similia bene differt.-Type: D.R.Congo, district Forestier Central, Ironga, alt.1080 m, May 1958, fl., fr., Gutz willer 2840 (holo-: BR; iso-: K).Suffrutex 0.50-2 m high; stems puberulent on two opposed bands, rarely all around.Lamina of the leaves 5.5-22 × 2.3-8.5 cm, elliptic to elliptic-oblong, cuneate to rounded at the base, acuminate at the tip, glabrous above, slightly puberulent along the nerves below; 5-7 pairs of lateral nerves; petiole puberulent, 0.5-5.5 cm long.Inflorescence spiciform, dense, on terminal axis and lateral branches, 3-21 cm long; bracts obovate to oblanceolate or elliptic-oblong, puberulent and minutely glandular, 6-12 × (2-)2.5-3.5 mm, acute to acuminate at the tip; bracteoles oblanceolate, 8.5 × 2.25 mm, with the same indumentum as the bracts; calyx 6 mm long, lobes 5 × 0.5-1.25 mm with the same indumentum as that of the bracts outside, puberulent and with numerous sessile glands inside; corolla white, 11-13 mm long, infundibuliform, densely pubescent outside with the longest hairs on the tube, and also minutely glandular; tube 6-7 mm long, 3-4 mm wide at the throat, provided inside with a ventral hairy reversed "V" below the palate and two rows of hairs beneath the stamens, dorsally with two rows of hairs, each running half way down from the crossing-point of a pairs of nerves; upper lip ovate, 5-6 × 4-6 mm, emarginate; lower lip 5-6 × 8-10 mm, with a small nerved palate at the throat, deeply trilobed (the lobes almost as long as the lip), lobes oblong, much longer in relation to the length of the lip than those of Tyloglossa species, the median one 5 × 3-3.5 mm, the lateral ones 5 × 2-2.8 mm; filament of the stamens glabrous except ventrally at their base, 4-6 mm long; thecae glabrous or almost so, yellowish, 1.5-1.75mm long, one above the  other, the upper one with a tiny spur up to 0.25 mm long, the lower one with a 0.6-0.75mm long spur; style 7-9 mm long, hairy at least in the lower half; ovary hairy.Capsule stipitate, puberulent, 2.3 cm long.Seeds pale yellow, 2.5 mm in diameter, tuberculate.Fig. 11.Distribution -A species of the Guineo-Congolian centre of endemism.Fig. 7. Herbaceous plant 35-100 cm high, ascending to prostrate, rooting at the nodes, glabrous.Lamina of the leaves narrowly elliptic to lanceolate, (1.5-)3-10 × (0.6-)1.2-3.6 cm, subacute at the tip, cuneate to attenuate at the base; 5-7 pairs of lateral nerves; petiole 0.3-3 cm long; bracts not imbricate, lanceolate, entirely green, acuminate at the tip, 5 × 1.5 mm, glabrous; bracteoles similar; calyx 5-6 mm long, lobes minutely glandular and shortly ciliate, 4.5-5.5 × 1 mm; corolla white, sometimes somewhat mauve, 7.5-11.5 mm long; tube 3.5-6 mm long, with hairs at the base of the sides of the rugula and below the stamens; upper lip ovate, 3.5-5.5 × 3.5-5 mm, two-toothed at the top; lower lip trilobed, 3.5-5.5 mm long, median lobe 3-4 × 1.6-2.8mm, lateral lobes 3-4 × 1-1.8 mm; filament of the stamens 2-4 mm long, hairy at the base; thecae 1.5 mm long, glabrous, the lower one with an acute spur 1 mm long; style 5-7.5 mm long, hairy in the lower 1/2-2/3; ovary glabrous, 1 mm long; disc 0.7 mm high.Capsule stipitate, 10-12 mm long, the upper swollen fertile part about 5 mm wide.Habitat -Riverbanks, Alchorneetum, semi-aquatic grasslands.Remark -Differs from J. betonica by its narrower entirely green and not imbricate bracts, by its narrower leaves, spindlier spike and its habitat, being strictly confined to riverbanks and semi-aquatic vegetations.J. betonica is known as a very variable species and the specimens from the Congo river could be considered only as an accommodation to that particular environmental conditions.However, there are no intermediates between J. betonica and the riparian J. al chorneeticola in the area, and the characters of the latter are very constant; otherwise, the complex J. betonica, including a lot of species of the section Betonica, has not yet been revised carefully; it seems therefore preferable to treat the riparian species as a distinct taxon.
The specific epithet 'alchorneeticola' meaning inhabiting the alchorneetum, is given after the name of the association Alchoorneetum cordifoliae Léonard (1950: 378) (syntaxonomic Braun-Blanquet system), which designates a riparian plants association which forms shrubby fringes along the rivers, with as characteristic taxon Alchornea cordifolia inter alia.
See remark under J. tutukuensis.BR; iso-: CAS, K).Suffrutex 1.20 m high with dense foliage; stem woody, up to 1 cm in diameter at the base, bark brown.Lamina of the leaves glabrous, narrowly elliptic, about five times longer than wide, 4.5-8 × 1-1.5 cm, subacute at the tip, cuneate at   the base, smaller on the short lateral shoots; petiole 0.4-1 cm long.Inflorescence spiciform, one-sided; bracts narrowly elliptic to lanceolate, acuminate, rather scarious, pale green, 11-13 × 3 mm, the outer ones glabrous, the inner puberulent and minutely glandular; bracteoles 13-14 × 1.75 mm, puberulent, minutely glandular and ciliate; calyx 16 mm long, lobes 15 × 1.5 mm, with the same indument as the bracts, long acuminate; corolla white, flushed with mauve, 31 mm long, puberulent outside; tube 15 mm long, 11 mm wide at the throat; upper lip triangular, 16 × 13 mm, two-toothed at the tip; lower lip 16 × 11 mm, trilobed, median lobe 4 × 4.5 mm, lateral ones 3.5 × 3 mm; filament of the stamens glabrous, 14 mm long, thecae 2 mm long, inserted one above the other, the lower one with a 2 mm long, strongly curved spur; style 25 mm long, hairy on two opposed sides in its lower half; ovary glabrous, 4-ovuled, 2 mm long; disc 0.7 mm high.Capsule unknown.Fig. 13.Distribution -A species from the Zambezian centre of endemism, endemic from Katanga, only known by the type.Fig. 9. Habitat -Gallery forest, around 1320 m.Remark -A very particular species, a small shrubby stout suffrutex having large corollas with the tube equalling the lips, the upper one being flat, whereas all the other largeflowered species of Justicia in Congo are more or less scandent shrubs with a corolla tube shorter than the lips, and a more or less hooded upper lip.Upemba, Kanonga, Feb. 1949, fl., fr., de Witte 5615 (holo-: BR; iso-: CAS, K, MO).

Justicia lenticellata
Shrublet or shrub 1-1.5(-2.5)m high.Stems with beige bark provided with numerous verrucose creamy lenticellae; young branches dark when dry, densely puberulous-velutinous.Lamina of the leaves ovate, cuneate at the base, acuminate to acute at the tip, strongly bicoloured, much lighter green to light blue-green below with a thin olive-green nervation, thin, fleshy, glabrous to sparsely pubescent above, densely pubescent on the nerves and sparsely so to glabrous elsewhere below, 2.7-9 × 1-4.5 cm; up to 5 pairs of lateral nerves; petiole up to 2 cm long.Inflorescences terminal and axillary, spiciform (2-)3-6 cm long, flowers by 2-3 in the lower part of the inflorescence, solitary in its upper part; axis puberulous and glandular; bracts inconspicuous, up to 4 × 1 mm, puberulous and glandular; bracteoles slightly larger than the calyx lobes; calyx lobes 7 × 1 mm, trinerved, puberulous and glandular; corolla 9.5-12 mm long, greenish white; tube 5 mm long and 3-3.5 mm wide at the throat, puberulent outside, inside pubescent, dorsally with two hairy "V" above and ventrally in its cylindrical part with three rows of hairs, two below the stamens and one central; upper lip ovate, 4.5-5 × 4 mm, emarginate, lower lip 4-4.5 × 4.5 mm, deeply trilobed, lobes very unequal, oblong, rounded at the tip, the median one the broader, 3.5-4 × 2.5-3 mm, the lateral ones 3-3.5 × 1-1.5 mm; filament of the stamens glabrous, 3-3.5 mm long; thecae 1-1.25 mm long, the upper one mucronate at the base, the lower with a spur 0.5-1 mm long; style 6 mm long, hairy at least sparsely in the lower half; ovary glabrous but slightly hairy at the tip, 1.5 mm long; disc 0.7 mm high (dissections of a 9.5 and a 10 mm long corolla).Capsule retrorsely puberulent, pale brown, 13-18 × 2.5-3 mm, stipitate.Seeds brown, verrucose (verrues spaced when ripe; verrues close, conspicuous and scabrid when unripe), 3 mm in diameter.Fig. 14.Distribution -A linking species of the Guineo-Congolian/ Zambezian regional transition zone and the Zambezian centre of endemism.Fig. 9. Habitat -Mateshi (dry evergreen forest or thicket), mushitu (gallery forest), damp woodlands close to streams, 1000-1350 m.Remark -Superficially resembling J. linearispica in its inflorescence, J. lenticellata is a shrub with conspicuous creamy lenticellae on the beige bark, not an herbaceous plant.The inflorescence is not a simple spike as in J. linearispica but is only partially so as the upper half of the inflorescence bears solitary flowers and the lower half shows bracts subtending 2-3 flowers.The inflorescences are terminal and axillary.Moreover the leaves are ovate, not linear-lanceolate, and their faces are strikingly contrasting in colour.
Erect to procumbent annual to perennial plant 35-130 cm high, stem almost glabrous or provided with appressed hairs and usually sparse to fairly numerous long glandular hairs.Lamina of the leaves lanceolate or narrowly elliptic, more rarely ovate, the upper ones two time narrower than the others, cuneate to shortly attenuate at the base, obtuse to acuminate at the tip, sparsely or more rarely fairly densely pubescent; petiole up to 1 cm long.Flowers few together in axillary completely condensed cymes; bracts ovate or narrowly elliptic to elliptic or oblanceolate, 2-5 × 0.8-2 mm, indument of fairly long stout multicellular hairs as for the leaves and with sparse long glandular hairs; calyx lobes narrowly triangular or narrowly lanceolate, 3-3.8 mm long at anthesis, slighly accrescent in fruit, with a white hyalin margin; corolla white to crimson, 5.2-8 mm long, including a tube 2.9-3.9 mm long; upper lip usually with marked purple nerves.Capsule 3.7-5.3mm long, acute at an angle of Habitat -Muhulu (dense dry forest), gallery forests, swamp forests, Brachystegia woodlands, savannas, 700-1950 m.Remark -J.abscondita has only weak differences with J. unyorensis S.Moore as their diagnostic characters overlap in some degree, which is illustrated by the Latin epithet 'abs condita' meaning 'hidden, mysterious, unclear'; J. abscon dita should perhaps be considered only as a subspecies, but as Hedrén (1989), who revised the whole Harnieria section, considered it as a distinct species under Justicia sp.A, pertaining to its J. striatagroup, we have decided to keep it at the specific rank.The two species could be considered as vicariant.
J. boaleri Hedrén, placed by Hedrén in the J. mollugogroup, resembles J. abscondita, but it has incompletely contracted partial inflorescences, some of them topping short lateral leafless branches reaching 2 cm long; it shows numerous moniliform hairs on the outer face of the bracts and on the corolla's bud, the other hairs being twice shorter than those of J. abscondita.The bracts are rather larger and more conspicuous than those of J. abscondita, the stems are not provided with long glandular hairs and the leaves are much narrower.Moniliform hairs (made of a long cell topped with Pl.Ecol. Evol. 146 (1), 2013 several superposed tiny cells above) are totally absent from all parts in J. abscondita, but are found in other species of the J. mollugogroup, as for instance J. syncollotheca Milne-Redhead.
Small decumbent herb with thin but hard stems 1 mm in diameter, rooting at the nodes, subquadrangular, retrorsely and shortly pubescent mainly on the angles or on two opposed sides; internodes 18-33 mm, the two or three uppermost ranging upwards between 10 and 3 mm long.Leaves small, lamina ovate or ovate-elliptic to elliptic-lanceolate, 9-16 × 3-10 mm, cuneate to subrounded at the base, obtuse at the tip, slightly coriaceous ar least when dry, glabrous except the slightly revolute shortly ciliate margin; petiole 1-3 mm long, absent in the upper leaves.Flowers few together in the leaf axils, with bracts and calyx shortly ciliate at the margin; bracts about 4 × 1 mm, oblanceolate; calyx 4 mm long, slightly accrescent in fruit, with narrowly triangular lobes 3 × 0.4 mm, green with a hyalin basis and a faint hyalin margin in the lower one third of their length; corolla deep pink, 6.5-7.5 mm long, sligthly puberulent outside; tube 3.5 mm long, 2.5 mm wide at the throat, inside with two adaxial hairy protuberances at 1.5 mm from the base and one abaxial median patch of hairs at the same level than the adaxial ones; throat black-purple spotted; upper lip 3.5 × 2.5 mm, oblong, emarginate at the tip, with longitudinal black purple streaks; lower lip 4 × 5.5 mm, usually unspotted, sometimes pink-red spotted, trilobed, median lobe 2 × 2 mm, lateral ones 2 × 1.5-1.75mm; base of the lower lip strongly gibbous, with a deep central furrow dividing it into two parts which are in turn transversely wrinkled; filament of the stamens glabrous, 1.5-2 mm long; anthers glabrous, 1.5 mm long, lower theca 1 mm long, upper theca 0.75 mm long, inserted 0.5 mm higher than the lower, both thecae bearing a membranous appendix at the tip, the lower theca with a basal white disc-like appendage 0.25 mm in diameter; style 3.5 mm long, sparsely hairy in the lower half.Capsule glabrous, 5.5-6 mm long, very shortly stipitate.Seeds 1 mm in diameter, cocoa brown, with more or less elongated transversely placed tubercules.Fig. 17.Distribution -A species from the Guineo-Congolian regional transition zone, endemic to Katanga, only known from the type-locality in Bas-Katanga.Fig. 18.Habitat -Savanna on loamy soil in valley.Vernacular name -Pempa (dial.Tshiluba).Remark -Justicia sejuncta belongs to the section Harnieria, J. mollugo-group.This group encompass small slender herbs, with condensed axillary inflorescences to solitary flowers, relatively closed corollas which never produce the 1-seeded weakly spiny fruits typical of the J. striata-group.
J. sejuncta is close to J. mariae with its discoid thecae's appendage, but seems to be outcrossing (stamens bending out of the corolla after pollen release) like J. richardsiae it also resembles in its habit.J. sejuncta is one of the three species of the group which has black-purple anthers, one of them, J. amanda, differing in its solitary flowers with much larger corollas (at least 15 mm long) and thecae provided with an acute spur, and the other, J. lovoiensis, with thecae bearing also a basal discoid appendage but differing in its erect habit, its very narrow, linear leaves and in its much larger corolla.
The epithet sejuncta, meaning separate, refers to the wide areal disjunction of this species in relation to the other members of the group, which all inhabit the Zambezian centre of endemism.
The first dichotomy of the key to the J. mollugo-group species given by Hedrén (1988) can be modified as herewith.Herbaceous erect plant 25-55 cm high; stems few together, slender, glabrous to pubescent.Leaves sessile with lamina linear to very narrowly elliptic, 1.5-3.5 × 0.1-0.2cm, glabrous to pubescent.Flowers axillary, solitary; bracts linear to narrowly oblanceolate, 6-10 × 0.7-0.9mm; calyx pubescent or glabrescent, 6-7 mm long, with acuminate lobes about 0.6 mm wide; corolla pink or bluish pink, with the upper lip paler and more or less strongly striped with dark purple; tube 6,5 mm long and 4 mm wide at the throat; upper lip ovateoblong, 5.5-6 × 4.5 mm, shortly slitted at the tip; lower lip elliptic-obtrapezoïdal, 7-8 × 6-8 mm, with a strong swelling bearing herring-bone venation at the base, trilobed; median lobe 3 × 2.5-3 mm, the lateral ones 3 × 2-2.5 mm; filament of the stamens glabrous, 3.5-4 mm long; anthers dark purple, with upper theca 1 mm long and dorsally pubescent, and lower theca 1.5 mm long, provided at the base with a broadened flattened, trapezoidal spur truncate and slightly bilobed at the tip, 0.3-0.4mm wide; style 7 mm long, pubescent with antrorse hairs.Capsule 8.5-9 × 3 mm, including the stipe 2 mm long.Seeds 2-3 mm in diameter, blackish, verrucose and slightly rugulose.Fig. 19.Distribution -A linking species between the Guineo-Congolian/Zambezian regional transition zone and the Zambezian centre of endemism.Endemic to Katanga in Congo.Remark -The species belongs to the section Harnieria and is close to J. mariae, which grows in the same kind of habitats.

Modification of key to species of J. mollugo-group
J. lovoiensis differs from the latter by its dark purple, not pale yellow anthers, its trapezoidal spur, its larger corollas and narrower bracts and leaves which are either glabrous or entirely pubescent, whereas they are pubescent only in the lower 1/5-1/4 in J. mariae.In addition, the flowers are always solitary in J. lovoiensis, whereas J. mariae can show clusters of several flowers (flowers axillary in both species).
Habitat -Evergreen forest along stream, gallery forests, 1100-1900 m.Remark -The species shows the same distribution as Aniso sepalum lewallei Bamps, which was first discovered in the Siguvyaye Valley in Burundi and a long time considered as endemic to that locality but was recently found in NE Tanzania, Mpanda Distr., Uzondo Plateau, at 5°29'S 30°32'E.Jus ticia pseudotenella was collected in the same general area as  A very characteristic suffrutescent plant up to 40 cm high with very large capsules in relation to the size of the plant.The plant rarely shows leafy flowering stems; it occurs mostly in frequently burned savannas and, after fire, the plant produces leafless flowering sprouts and afterwards new purely vegetative leafy shoots.In the field, tufted leafless flowering and fruiting shoots are the most common form of the species; less often both leafless and leafy shoots are produced at the same time and can be seen on the same thick rootstock, the rarest form being the leafy flowering shoot (see holotype), which can apparently develop only in case of absence of fire.The species blossoms en masse after savanna fires.
J. bequaertii has been overlooked in BR, as it was only represented by the type, a flowering leafy shoot.All the other specimens were kept in the unidentified material probably because having for the main part of them only leafless flowering stems, they do not look similar to the holotype at first sight; a few specimens only have separate vegetative and flowering stems.Only two specimens bearing leafy flowering stems have been seen, one from Zambia and one from Katanga.
The species was described as Monechma praecox by Milne-Redhead because it produces only two seeds, but the seeds in Monechma are always smooth whereas in Justicia they are ornamented, and there are four ovules; two of them can abort before maturity, which is the case here.Description of the species -Leaves subsessile or shortly petiolate, lamina oblanceolate to narrowly elliptic, 2.2-8 × 0.8-2.2cm, rounded or more rarely acute at the tip, light green to yellowish green when dry. Inflorescence a loose panicle of long spikes or narrow spiciform branches most often on leafless stems resprouting after fire (one or several flowers at the axils of the bracts: often one flower per bract in the upper part of the inflorescence and 2-3 flowers, sometimes in shortly pedunculate condensed fascicles, at the axils of the lower bracts); corolla white or cream to yellow, normally with a red-brown blotch or purple to brown spots at the throat, 8.5-12 mm long, upper lip hooded, lower lip deeply trilobed, the median lobe twice as broad as the lateral ones; anthers green-yellow.Capsule densely puberulent, yellow brown, 2.2-3.7 cm long, held parallel to the axis of the inflorescence, as the flowers.Seeds 2.6-8 × 5-7 mm, rugulose-tuberculate, greenish-cream, with a vertical median ridge.Fig. 21.

Additional record
An additional specimen of Justicia scutifera (Champluvier 2002) has been found in the unidentified material of Di cliptera in BR: D.R.Congo, district du Kasai, Panzi, 1925, Vanderyst 16937 (BR).The species is now represented in BR

Figure 1 -
Figure 1 -Justicia gladiatotheca pollen grain.A, apertural view; B, detail of the pore and of the exine of the raised band, colpus and pseudocolpus; C, mesocolpial view; D, detail of the mesocolpial exine; E, polar view.SE micrographs from Duvigneaud & Timperman 2729.

Figure 5 -
Figure 5 -Justicia nanofrutex pollen grain.A, apertural view; B, detail of the pore and of the trema area with insulae; C, mesocolpial view; D, detail of the mesocolpial exine.SE micrographs from de Witte 3785.

Figure 19 -
Figure 19 -Justicia lovoiensis.A, habit; B, two leaves of two different stems; C, leaf of another plant; D, flower, E, opened corolla, F, pistil, G, detail of the spur; H, one valve of the capsule; I, seed.A, B & D-I from Quarré 3045; C from Schaijes 2193.