Marsilea - Marsileaceae

Marsilea farinosa Launert ssp. farinosa

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

 

 

 

 

Synonyms

Common name

Description

Rhizome rather stout, up to 2.5 mm in diameter, silvery-grey or brown, with hairs or hairless; internodes usually very short, rarely up to 5 cm. Floating form: stipe up to 20 cm long. Leaflets up to 10-21 × 11-22 mm, broadly obdeltate, almost hairless, outer margin rounded, wavy. Dry land form: stipe up to 12 cm long, with bristly hairs. Leaflets up to 4-15 × 3-15 mm, obdeltate, set with a mixture of hairs, becoming subglabrous with age, outer margins lobed. Sporocarps: in clusters at the base of the stipe, bean-shaped, 4.2-7 mm long, 2.5-4.5 mm high, 1.5-2.3 mm thick, upper side straight or concave, under and outer side rounded, vertical cross-section rectangular; lateral ribs 8-11, not conspicuous in mature specimens; raphe present, extending 1/2–2/3 the length of the base of the sporocarp; veins (as seen on the interior surface) not anastomosing; lower tooth absent or very shallow hump, upper tooth present but usually rather inconspicuous, sharply obtuse to acute. Sporocarp densely covered with hairs of 2 kinds, erect and flattened, which in the dried state cause the powdery greyish appearance of the sporocarp. Sporocarps set at an angle of 90° to the pedicel; pedicels 8-15 mm, erect or arching, free, relatively slender, flexible, (4–)8–15(–25) mm long, arising from the axil of the stipe, with bristly hairs. Sori 8–11.

Notes

It differs from other species by its hispid appearance created by the 2 kinds of hairs.

Derivation

farinosa: powdery or with meal-like covering, alluding to the greyish appearance created by the hairs that cover much of the plant.

Habitat

Woodland and dry woodland savanne in dry, sandy riverbeds and seasonal vleis and pans.

Distribution worldwide

See African distribution.

Distribution in Africa

Angola, Botswana, Ethiopia, Kenya, Mozambique, Namibia, South Africa, Tanzania , Zimbabwe.

Growth form

Aquatic, terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 73 - 74. (Includes a picture).
  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Pages 244 - 246. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 481 - 482. Not divided into different subspecies. (Includes a picture).
  • Launert, E. (2003) Marsileaceae.Flora of Tropical East Africa, Pages 13 - 14. (Includes a picture).
  • Roux, J.P. (2009) Synopsis of the Lycopodiophyta and Pteridophyta of Africa, Madagascar and neighbouring islands. Strelitzia 23, South African National Biodiversity Institute, Pretoria. Page 56.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta.Southern African Botanical Diversity Network Report, 13 Pages 175 - 176.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta.Flora Zambesiaca, 0 Page 65. Not divided into different subspecies (Includes a picture).
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