Callitriche brutia subsp. brutia, Petagna, 1787

Lansdown, Richard V., 2022, The genus Callitriche (Plantaginaceae, Callitricheae) in Australasia and Oceania, Phytotaxa 547 (3), pp. 243-284 : 251

4a. Callitriche brutia subsp. brutia

Description (after Lansdown 2008):—Stem, leaf and axillary scales present. Leaf bases connate. Lingulate leaves 4–16 mm long × 0.1–1.7 mm wide, narrowly linear, more or less parallel-sided, apex expanded, with a long, fine, broad or narrow notch; expanded submerged or floating leaves narrowly elliptic to oblong 1.8–17.8 mm long × 0.8–3.6 mm wide, 3(–5)-veined, petiole 0.1–10.2 mm long; apical leaves form a floating rosette; leaves of terrestrial plants linearelliptic to elliptic, 2.4–5.5 mm long × 0.3–0.8 mm wide, 1(–3)-veined. Flowers generally solitary, a ♂ and ♀ in a pair of axils occasionally more than one in an axil. Bracts translucent, whitish, falcate, caducous, 0.2–1.8 mm long. Styles persistent, tightly reflexed and appressed to sides of fruit from the initial stages of development, so that the styles pass either side of the stem to touch the anther in the opposed axil, ≤ 4.1(–4.3) mm long. Filament erect, ≤ 1.2 mm long; anthers 0.1–0.5 mm long × 0.1–0.6 mm wide, quadrilocular; pollen colourless, translucent. Fruits not strumose, subsessile or with pedicel ≤ 12 mm long, more or less as wide as or wider than high, blackish or maroon when mature, 0.7–1.6 mm long × 0.7–1.8 mm wide, narrowly winged.

Illustrations: —Figures in Lansdown (2008) pages 132–135; Figures 11 (a–b), 11A(a–c) in Mason (1959); figures 1J–L in Orchard (1980). Fig. 1d .

Recognition: — C. brutia can be distinguished from all other Callitriche species by the reflexed style which initially crosses the stem to contact an anther in the opposite leaf axil and of which the remains are typically appressed to the commissural groove of mature fruit ( Fig. 1d ). No other Callitriche species in the region has colourless pollen.

Distribution: —Non-native to the region, where it occurs throughout Victoria and southern New South Wales ( Webb et al. 1988, Jeanes 1999), with a few records from South Australia and a cluster of records south of Perth in Western Australia, as well as from between Matakohe and Ruawai near the Karipara Harbour on North Island and Lake Elterwater on South Island in New Zealand ( Fig. 4 ). Outside Oceania, C. brutia is native throughout much of Europe, from Iceland and the Faroe Islands, through Scandinavia to Poland and the Czech Republic and throughout the Mediterranean basin east to Greece, as well as from Greenland, Morocco, Iran and the Caucasus. C. brutia also occurs as a non-native on the west coast of North America, from Oregon north into British Columbia ( Lansdown 2009).

Habitats and Ecology: —In Australia C. brutia is described as growing in water or on mud ( Walsh and Entwistle 1999) in drains, creeks and dams ( Bean 2007). Herbarium specimen labels indicate that it occurs in water up to 50 cm deep, typically in seasonally inundated areas, in swamps, roadside pools, ponds, lake margins and floodplains, in open woodland, such as Eucalyptus camaldulensis Dehnh. (1823: 20) stands or in sedge-lands. In its native range, C. brutia subsp. brutia typically occurs in ephemeral water bodies and in the draw-down zone of standing waters on the margins of lakes ( Lansdown 2008). 0–950 m elevation in its native range; no information on elevation in the region.

Notes: —Most records on the Australian Virtual Herbarium appear to have been correctly determined and they are mainly accepted here for mapping purposes.

Conservation Status: —Least Concern (LC) ( Lansdown 2014a).

Additional material studied:— AUSTRALIA: NEW SOUTH WALES. Western Wanganella Swamps , 17 September 1990, J. Roberts 671 ( CANB 601529 ) ; Albany , 24 November 1993, S.W. Jacobs 6989 ( NSW) . VICTORIA. near Dimboola , 18 September 1892, F.M. Reader 8 ( MEL 2248528 ) ; Winton Swamp, Benalla , 18 September 1960, H.I. Aston 621 ( NSW 674137 , US 610390) ; 26 August 1967, C. den Hartog 195 ( MEL 2380258 ) ; Victoria Valley, Dunkeld , 21 October 1969, B.L. Briggs 2905 ( NSW 131720 ) ; Snowfields Mt. Reynard, 16 December 1992, D.E. Albrecht 5330 ( CANB 9405439 ) . NEW ZEALAND: SOUTH ISLAND. Lake Elterwater , Marlborough, 23 January 1955, R. Mason 3160 ( CANB 589572 , MEL 2387238 , NSW 674138) .

Figures

FIGURE 1. Fruits of Callitriche in Oceania and Australasia: a—C. antarctica, b—C. aucklandica, c—C. brachycarpa, d—C. brutia, e—C. capricorni, f—C. chathamensis, g—C. cyclocarpa i face on and ii end on, h—C. cycloptera, i—C. deflexa, j—C. fuliginea.

FIGURE 4. The distribution of specimens of C. brutia in Oceania and Australasia based on records held by AVH.

FIGURE 11 C. muelleri Tiritiri Matangi, North Island, New Zealand, 2011 © R.V. Lansdown