Cirrulicarpus nanus (J.Agardh) Womersley
Transactions of the Royal Society of South Australia 256 (1973)
Conservation Code:
Not threatened
Naturalised Status: Native to Western Australia
Name Status:
Current
Scientific Description
John Huisman & Cheryl Parker,
Monday 20 June 2011
Habit and structure. Thallus dark red, flattened, irregularly alternately to subdichotomously branched, sometimes proliferous to polychotomous, 5–15 cm high, stipitate at the base; branches with rounded apices, often basally constricted, varying in breadth and broadest either in their mid or apical regions, with a smooth to slightly irregular margin, mostly (0.2–)0.5–1 cm broad, occasionally with older parts to 3 cm broad; substance firm and somewhat cartilaginous, only slightly adherent to paper on drying. Holdfast discoid, 2–6(–8) mm across; epilithic. Structure. Thallus 220–450(–600) µm thick, consisting of 4–6 layers of cortical cells and a moderately dense medulla of filaments 3–6 µm thick; outer cortical cells in surface view 2–5 µm across, compactly arranged and irregularly isodiametric, in sectional view isodiametric; medulla with some lightly staining stellate cells.
Reproduction. Sexual thalli dioecious. Carpogonial branch systems arising in the inner cortex, polycarpogonial with 2–5 carpogonial branches; supporting cell elongate and often somewhat dumb-bell shaped or basally swollen, sometimes once lobed, bearing up to 6 elongate and clavate (rarely lobed) subsidiary cells or first cells of the carpogonial branches; second cells of carpogonial branches elongate, carpogonia with prominent, coarse trichogynes. Fusion cell unknown. Auxiliary cell systems apparently similar to carpogonial branch systems but with fewer, smaller and shorter cells and without a carpogonium. Cystocarps large, 1–2 mm in diameter, scattered in groups on the surface of upper branches, hemispherical and ostiolate; carposporophyte consisting of small groups of spherical to ovoid carposporangia (10–15 µm across) interspersed with slender gonimoblast filaments. Male thalli with spermatangia covering the ends of branches, cut off from elongate outer cortical cells, ovoid, 1.5–2 µm in diameter. Tetrasporangia scattered, cut off from mid cortical cells and lying just below the surface, 25–38 µm long and 10–15 µm in diameter, obliquely divided with intersecting walls.
Distribution. Pearson I., S. Aust., to Port Phillip Heads, Vic.
[After Womersley, Mar. Benthic Fl. Southern Australia IIIA: 241–242 (1994)]
