Electronic Flora of South Australia Species Fact Sheet
Phylum Magnoliophyta – Subphylum Seagrasses – Class Liliopsida – Subclass Alismatidae – Order Potamogetonales – Family Zannichelliaceae
Selected citations: Aston 1973: 318, fig. 128 (i-p). Bentham 1878: 180. Green 1981: 5. Jessop 1978: 76. Willis 1970: 70.
Zannichellia preissii Lehmann 1846: 3.
Althenia preissii (Lehmann) Ascherson & Graebner 1907: 160. Blackall & Grieve 1954: 8.
Monoecious; slender rhizomatous herb (Figs 18B, 19J), probably annual. Rhizomes very fine, 0.3–0.5 mm in diameter, with an amplexicaul scale at each node, and usually at each alternate node 1–4 roots and an erect shoot 5–20 (–50) cm tall. Leaf sheath (Fig. 19J,N) membranous, somewhat inflated, 3–10 mm long, ligule deeply bifid; blade narrow-linear, 1–8 cm long, mostly 0.1–0.2 mm broad; apex (Fig. 19K,O) usually tapering to an acute or acuminate tip. Squamules (Fig. 19J) filiform, 1.0–2.0 mm long. Fertile shoots (Fig. 19J) flexuous, much-branched, 20–50 cm tall, most branches bearing 1 or 2 female and 1 or 2 male flowers clustered together within the subtending leaf sheaths, some clusters with all female flowers particularly in the upper branches of the inflorescence. Male flower (Fig. 19L) with pedicel 3–5 mm long at anthesis; tepals 3, united in lower part, 0.2–0.4 mm long; stamen with pollen sacs about 1 mm long. Female flowers (Fig. 19L,P) on pedicels 0.5–1 mm long, not (except for the styles and stigmas) projecting beyond the leaf sheaths; tepals 1–2.5 mm long, elliptic, apex deeply bifid and irregularly dentate; carpophore 0.2–0.5 mm long; style slender, stigma narrow, obliquely funnel-shaped with a serrate margin. Fruit (Fig. 19M,Q,R) asymmetric oblong, about 2 mm long, L/B 1.5–2.5 (–3), shorter than (or equal to) the tepals and remaining enclosed within them. Tepals frequently whitish and conspicuous around the dark-brown to black fruits.
Type from the Canning River estuary, Perth, W. Aust., in salt water. (Preiss No. 1879, Nov. 1841); in LD.
Selected specimens: The type and Peel Inlet, W. Aust., 1 m deep, temporary freshwater pool (Carsiairs, 12.ix.1982; ADU, A53395).
Distribution: No marine specimens have been seen. The type locality in the Canning River estuary has been greatly modified in the past few decades and no Lepilaena has been found in that locality recently.
Taxonomic notes: L. preissii occurs in fresh to brackish to saline water of seasonal or intermittent coastal and inland waters in W. Aust. (in the Perth to Esperance area), S. Aust. (south east), Vic. (western shores of Port Phillip Bay), Flinders I. (Bass Strait) and Tas.. Brock & Lane (1983) record L. preissii in salinities up to 150‰
Aston (1973, p. 318) records monoecious and dioecious plants in Victoria. The type (Figs 18B, 19N–R) is monoecious and all Western Australian specimens examined are also monoecious. L. cvlindrocarpa and L. preissii have frequently been confused and further work on the genus is essential.
ASCHERSON, P. & GRAEBNER, P. (1907). Potamogetonaceae. In Das Pflanzenreich (ed. A. Engler) 4, II, Heft 31, 1–184. (W. Engelmann: Leipzig.)
ASTON, H. (1973). Aquatic plants of Australia. (Melbourne University Press: Melbourne.)
BENTHAM, G. (1878). Flora Australiensis: A Description of the Plants of the Australian Territory. Vol. 7. (Reeve: London.)
BLACKALL, W.E. & GRIEVE, B.J. (1954). How to know Western Australian Wildflowers. Part I. (University of Western Australia Press: Perth.)
BROCK, M.A. & LANE, J.A.K. (1983). The aquatic macrophyte flora of saline wetlands in Western Australia in relation to salinity and permanence. Hydrobiologia 105, 63–76.
GREEN, J.W. (1981). Census of the Vascular Plants of Western Australia. (Western Australian Herbarium: South Perth.)
JESSOP, J.P. (1978). J.M. Black's Flora of South Australia. 3rd edn. Part I. (Govt. Printer: Adelaide.)
LEHMANN, J.G.C. (1846). Plantae Preissianae sive Enumeratio Plantarum, quas in Australasia Occidentali et Meridionali-occidentali annis 1830–1841 collegit Ludwig Preiss. Vol. 2. (Meisner: Hamburg.)
MUELLER, F. (1874). Fragmenta Phytographiae Australiae. Vol. 8, 141–304. (Govt Printer: Melbourne.)
WILLIS, J.H. (1970). A handbook to plants in Victoria. Vol. 1. 2nd edn. (Melbourne University Press: Melbourne.)
The Marine Benthic Flora of Southern Australia Part I complete list of references.
Womersley, H.B.S. (31 May, 1984)
The Marine Benthic Flora of Southern Australia
©Board of the Botanic Gardens and State Herbarium, Government of South Australia
Illustrations in Womersley Part I, 1984: FIGS 18B, 19 J–R.
Figure 18 enlarge
Fig. 18. A. Lepilaena cylindrocarpa (ADU, A53620). Habit of male (lower left) and female plants. B. Lepilaena preissii. Part of the type sheet. C. Lepilaena marina. The type sheet.
Figure 19 enlarge
Fig. 19. A–I. Lepilaena cylindrocarpa (ADU, A53620). A. Portion of leaf (adaxial view) showing blade (bl.) and sheath (sh.) junction. Note ligule (l.) deeply cleft into 2 auricles (a.) and a pair of squamules (sq.) adhering to the sheath base. B. Junction of leaf blade and sheath (side view) showing ligule (l.), auricles (a.) and squamules (sq.). C. Leaf apices. D. Portion of male inflorescence. E. Portion of male inflorescence showing 3 male flowers, lowest (oldest) with dehisced pollen sacs, mature flower with ripe pollen sacs and immature flower enclosed in sheath. Note pedicel (pe.), pollen sacs, tepals (t.) and squamules (sq.). F. Portion of female inflorescence. G. Young female flower showing pedicel (pe.) and tepals (t.) enclosing the carpels with styles projecting. H. Mature fruit showing 3 achenes projecting beyond tepals. 1. Mature achene. Note carpophore (c.p.) and stylar beak (be.).
J–M. Lepilaena preissii (ADU, A53395). J. Portion of monoecious plant with inflorescence. K. Leaf apices. L. A mature male and an immature female flower in position, subtending leaves removed. Note squamules (sq.), tepals (t.) and pedicels (pe.). M. Mature fruit showing 3 achenes enclosed within the tepals. N–R. Lepilaena preissii (Type specimen). N. Junction of leaf blade (bl.) and sheath (sh.) showing ligule (l.) and auricles (a.). 0. Leaf apices. P. Female flower (two stigmas damaged, one missing), with pedicel (pe.) and tepals (t.). Q. Mature fruit showing achenes enclosed within tepals (t.). R. Single achene showing stylar beak (be.) and carpophore (c.p.).
State Herbarium of South Australia