Barleria glutinosa Champl., 2011

Dominique Champluvier, 2011, New and overlooked Acanthaceae taxa from D. R. Congo, Rwanda and Burundi: (1) the genus Barleria, Plant Ecology and Evolution 144 (1), pp. 82-95 : 85-86

Barleria glutinosa Champl. , sp. nov.

B. molensis affinis sed propter spinas multo parviores, usque ad 1.2 cm nec 1.3–3 cm longas, corollam breviorem, 4–5 cm nec 6.5–9 cm longam, tubo breviore, 2.8–3.3 cm nec 5–7 cm longo, extus pilis glandulosis et pilis simplicis brevis nec sole pilis simplicis munito, capsulam parviorem 1.5 cm contra 2.5 cm bene differt; ab omnibus alteribus speciebus Barleriae propter omnes partes valde glutinosas villosasque, flores solitarias pedicellatas, corollae tubum in dimidio inferiore cylindricum et in dimidio superiore infundibuliformem bracteolasque patentes bene distinguitur.

– Type: D.R.Congo, District du Haut-Katanga, Mt Mumbwelume, alt. 1820 m, Apr. 1987, Kisimba & Muzinga 46, fl (holo-: BR; iso-: CAS, EA, K, LISC, MO)

Suffrutex 30–40 cm high, entirely glutinous by the presence of a dense glandular pubescence, all parts also villous. Lamina of the leaves ovate-elliptic, up to 3.3 × 1.6 cm; petiole up to 5 mm long. Flowers with pedicels 5–7 mm long, solitary or by two on peduncles (1–)2–3 cm long; bracteoles spreading, lanceolate, spiny, up to 12 mm long and 2 mm wide at the base; calyx lobes lanceolate, the posterior one acute at the tip,15 × 4 mm, the anterior one bifid at the tip,14 × 4 mm, the lateral ones smaller and much narrower; corolla 4–5.5 cm long, pale blue or pink, rarely white, with purple marks in the throat; tube 2.8–3.3 cm long, 4.5–5.5 wide at the throat, cylindrical in the lower half, infundibuliform in the upper half, covered with long glandular hairs and short sparse simple hairs; lobes 1.8–2 × 1–1.3 cm, elliptic, mucronate at the tip, the two upper ones slightly smaller than the three lower ones; filament of the two fertile stamens 2.2 cm long, villous at the base, anthers 5 mm long, the three staminodes with filament 5 mm long and reduced anther (stamens from corolla 5 cm long); style 4–5 cm long. Capsule about 15 × 5 mm, glabrous, black, glossy.

Distribution – Species from the Zambezian centre of endemism. Fig. 4 .

Key to the vicariant pair B. molensis / B. glutinosa

1. Spines 1.3–3 cm long; corolla pure white, 6.5–9 cm long, tube 5–7 cm long, provided outside only with non-glandular hairs; capsule 2.5 cm long...........…...........................................……... B. molensis

1. Spines shorter, up to 1.2 cm long; corolla pale blue or pink, rarely white, with purple marks in the throat, 4–5 cm long, tube 2.8–3.2 cm long, provided outside with rather sparse long glandular hairs and numerous short non-glandular hairs; capsule 1.5 cm long............................................... B. glutinosa

Other collections examined – Zambia: Rufunsa, Jun. 1958, Fanshawe 4542, fl, fr (K); 50 miles E of Lusaka, alt. 1300 m, Jun. 1956, King 381, fl (K); 18 km E of Rufunza, Lusaka distr., alt. 1000 m, Sep. 1972, Kornas 2057, fl, fr (K); 17 miles E of Rufunsa, alt. 1100 m, May 1961, Leach & Rutherford­Smith 11095, fl, young fr (K); Luangwa River, Jun. 1957, Munch 460, fl, fr (K); 116 miles E of Lusaka on Great East Road, Apr. 1952, White 2692, fl (K, BR); 10 miles W of Kacholo Rest House, Great East road, May 1952, White 2888, fl (K).

Habitat – Brachystegia woodlands, around 1800 m in D.R.Congo; sandy stony soil on hillsides, Brachystegia allenii and B. mango woodlands on escarpments with quartzitic shallow soils or on steep rocky slopes, dry rocky roadside scarps, alt. 1000–1300 m, in Zambia.

Figures

Figure 4 – Distribution map of Barleria glutinosa, B. molensis, B. cinerea and B. obtecta.