Bolboschoenus maritimus (L.) Palla

Cyperaceae, K Hoenselaar, B. Verdcourt & H. Beentje. Hypolytrum, D Simpson. Fuirena, M Muasya. Flora of Tropical East Africa. 2010

Type

Types: Sweden, Roslagen, Linnaeus s.n. (UPS, Herb. Celsius 2: 212, lecto.); Sweden, E Roslagen, Borstill, 2 km W of Kalla near Husbacka, Nilsson 9515 (UPS, epitype; BR, H, MO, NU, NY, isoepitypes)

Morphology General Habit

Perennial 0.4–1.2 m tall with swollen stem bases and stiff spreading rhizomes.

Morphology Stem

Stems triangular, glabrous, 2–5(–10) mm thick, covered in the lower half by green leaf sheaths with brown slightly hairy throats; blades long and flat, the upper overtopping the stem, 25–40 mm long, 5–10 mm wide, scabrid on keel and margins

Morphology Reproductive morphology Inflorescences Bracts

Main bracts 8–15 cm long and overtopping the inflorescence

Morphology Reproductive morphology Inflorescences

Inflorescence compound, open, with terminal cluster of several sessile spikelets and with small heads of 1–3 sessile spikelets, the heads on unequal branches 1–3 cm long, the total number of spikelets per inflorescence being 20–40(–50).

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets golden brown to reddish brown, elongate, (5–)15–40 mm long, 3–5 mm wide.

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes golden or pale to dark brown, 5–6 mm long, emarginate and with a mucro

Morphology Reproductive morphology Flowers Perianth

Perianth segments 6, white or brown, linear with retrorse bristles

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens with long flattened filaments

Morphology Reproductive morphology Fruits

Nutlets pale brown becoming dark brown, obovoid, 2–2.6(–3) mm long, 1.4–1.8(–2.3) mm wide, smooth, bluntly acuminate, convex on one side and flattened on the other

Figures

Fig. 4, p22

Ecology

Seasonal swamps, often on black cotton or saline soil, muddy river banks, lake flood plains, ricefields; 10–1350 m

Note

Dr Jane Browning informed the editor just before publication that she believes B. maritimus does not occur in tropical Africa, and that our taxon should be named B. glaucus (Lam.) S.G. Smith in Novon 5: 101 (1995); basionym Scirpus glaucus Lam., Tabl. Encycl. 1: 142 (1791). Type: Senegal, Rousillon s.n. (P-Lam., holo.). Browning, Gordon-Gray, Smith & van Staden published on this subject in Nordic. J. Bot. 1: 475–482 (1998).

Distribution

Range: Mauretania, Senegal, Mali, Sudan, Ethiopia, Somalia, Angola, Malawi, Mozambique; widespread in temperate and tropical regions Flora districts: K1 K4 K7 T2 T3 T4 T5

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Perennial with long hardened stolons ending in tubers or stems; stems 40–120 cm long and 2–5 mm thick, sharply triangular, pith-filled or hollow

Morphology Leaves

Leaf-blades 25–40 cm long and 3–10 mm wide, flat; sheaths greenish

Morphology Reproductive morphology Inflorescences

Inflorescence with clusters of spikelets on branches of very unequal length (usually 0.5–3 cm long); total number of spikelets usually 5–40; largest involucral bracts usually 8–15 cm long, erect or spreading, similar to the leaf-blades

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 10–50 mm long and 3–5 mm wide, ovate to elongate and often somewhat curved, golden brown to reddish brown

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes 5–6 mm long, ovate with midrib excurrent; margin and surface with minute hairs

Morphology Reproductive morphology Flowers Perianth

Perianth-bristles 6

Morphology Reproductive morphology Flowers Gynoecium Style

Style with 3 branches

Morphology Reproductive morphology Fruits

Nutlet 2–2.6 x 1.4–1.8 mm, 3-angular, dark brown and smooth as mature.

Distribution

S2, 3; pantropical as well as in temperate regions.

Ecology

Altitude: near sea-level to 100 m.