Drosera indica, Linnaeus, 1753

Rjosk, A., Neinhuis, C., Monizi, M. & Lautenschläger, T., 2022, Synopsis of the genus Drosera (Droseraceae) in Angola and the Democratic Republic of the Congo, Blumea - Biodiversity, Evolution and Biogeography of Plants 67 (1), pp. 1-14 : 9

6. Drosera indica L. — Fig. 8

Drosera indica L. (1753) 282;Oliv. (1871) 402; Diels (1906) 77;G.C.C. Gilbert (1951) 551; Keay (1954) 122; J.R. Laundon (1959) 2, (1970) 25; Oberm. (1970) 201; J.R. Laundon (1978) 64;Akoègn.et al. (2006) 539;A.S.Rob. et al. (2017) 1418. —

Lectotype (designated by Laundon (1959) Droseraceae 2): P. Hermann s.n. (lecto BM), India.

Synonyms in Africa only: Drosera minor Schumach. (1827) 167. — Type: C.F. Schumacher s.n. (holo C, not seen), Guinea.

Slender, annual, caulescent herb ( Fig. 8b ). Stems 3–50 cm long, erect or matted, canaliculate, (sparsely) glandular, green. Leaves alternate to spirally arranged, evenly spaced, erect, old leaves reflexed; stipules absent, a pair of setae-like hairs at the base of the leaves; lamina linear to filiform, 1–10 cm by 0.4–4 mm, apex long acuminate, adaxial surface and margins bearing tentacles, abaxially glabrous, green ( Fig. 8a ); petiole 0.1–1.5 cm long, glandular. Inflorescences cymose, with 3–20 flowers, recurved; peduncles 0.5–15 cm long, arising laterally from the stem, glandular; bracts linear to spathulate, c. 2.5 mm long, apex more or less dentate; pedicels 0.2–2 cm long, glandular. Sepals 5, ± lanceolate, 2–5 by 1–2 mm, apex acute or obtuse, glandular. Petals 5, spathulate to obovate, 4–8 by 2.5–6 mm, pink to purple, mauve (in Asia also white). Stamens 5; filaments 3–5 mm long, white or pink; anthers yellow. Pollen in tetrads, tetrads c. 50–55 µm diam, single grains c. 25 µm diam, long echinate ( Fig. 8e ), echini narrowly conical, 2–3 µm long, occurring in medium density, with short clavate sculptural elements between echini. Pistil: ovary subglobose to ovoid, 1.5–3 by c. 2 mm, glabrous; styles 3, bipartite to the base, branches c. 2.5 mm long, ascending. Seeds globose to ovoid, 0.4–0.5 by c. 0.3 mm, apiculate, black, testa reticulate ( Fig. 8f ).

Distribution — Widespread in tropical Africa, Asia and Aus- tralia ( Fig. 8c ).

Habitat & Ecology — Wide range of seasonally wet habitats (e.g., swamps, pools, rivers and lake shores).

Additional specimens (see Fig. 8d for province map). ANGOLA, Benguela, Tchiyaka, 20 km nördlich von Quingenge, gefunden auf nasser Felsplatte, alt. 1750 m, 13 Feb. 1955, J.B. Damann s.n. (sine nummero) ( ZT) ; Huíla, Humpata , alt. 1800 m, 5 Apr. 1937, J. Gossweiler 11104 ( COI) ; Entre lá da Bandeira e Humpata , alt. 2000 m, 6 May 1937, A.W. Exell & F.A. Mendon ҫa 2599 ( COI) ; Lubango, entre Palaca e o Perimetro Florestral , alt. 1960 m, 15 Apr. 1960, E.J. Mendes 3613 ( COI) ; Moxico, Cameia National Park , Biodiversity Observatory , S11°31' E20°54', alt. 1126 m, 3 May 2016, Finckh & Zigelski 143317 ( HBG) . – DRC, Haut-Katanga/Haut-Lomami, Parc National de l’Upemba , Entre la riv. Kanonya et la riv. Lukange, 19 Feb. 1949, G.F. de Witte 5544 ( BR) ; Haut-Uele, Mai-Kuku , 6 km au-delà Gombari, alt. 1200 m, 16 July 1937, J. Louis 4540 ( BR) ; Parc National de la Garamba , route Dungu – Bagbele (Ukwa) , km 17 de Bagbele, 25 Aug.1952, G. Troupin 1991 ( BR) ; Ituri, Entre Jaradje et Aba , July 1931, J. Lebrun 3429 ( BR, P) ; Kasai-Central, Samusambu , 65 km de Sandoo, Lulua , 6 June 1932, Overlaet 1252 ( BR) ; Kinshasa, Kinshasa , 17 May 1915, Bequaert 7612 ( BR) ; Congo-Kinsuka, près Leopoldville , July 1944, Coutreaux 1011 ( BR) ; Kinsuka , 28 May 1947, E. Jans 490 ( BR) ; Ile des Mimosas, Ngaliema , 1 June 1983, H. Breyne 4624 ( BR) ; Kongo Central, Gombe Matadi , Jan.1950, H. Callens 2594 ( BR) ; Tshopo, Niomgaza (Uili-Nepoko) , June 1931, J. Lebrun 3174 ( BR) .

Figures

Fig. 8 Drosera indica L. a. Leaf shape showing linear to filiform lamina; b. general morphology: caulescent,, spiral leaves and laterally arising inflorescences; c. distribution according to the literature; d. province map of Angola and DRC with localities of examined herbarium specimens; e. pollen in tetrads with long echinate, narrowly conical sculpture elements in medium density; f. dry seed, 370 × 300 µm, with conspicuous reticulate pattern. — Scale bars: a = 1 cm; b = 2 cm; e = 10 µm; f = 100 µm.