Electronic Flora of South Australia Species Fact Sheet
Phylum Rhodophyta – Class Florideophyceae – Order Gigartinales – Family Caulacanthaceae
Selected citations: Davey & Woelkerling 1980: 59. Min-Thein & Womersley 1976: 50, figs 17, 59. Post 1936: 68; 1964: 252. Tseng 1942: 143, fig. 2.
Catenella opuntia sensu Harvey 1863: pl. 296.
Catenella opuntia var. elatior J. Agardh 1876: 588. Kylin 1932: 34.
Thallus (Fig. 156D) dark brown-red to purple, fading to yellow-brown, in dense tufts or masses (1–) 2–10 cm high and across, much branched from the upper end of elongate-ovoid segments (1–) 3–6 (–10) mm long and 1–2 mm broad, upper segments terete, becoming compressed below (Fig. 154G). Haptera numerous, developing at the distal ends of segments which then produce 1–3 new segments just subterminally. Usually on mangroves or jetty piles, sometimes epilithic. Structure (Fig. 154H) with one or a small group of apical cells, producing several slender medullary filaments, each cell with a single lateral, which form a laxly branched, reticulate, medulla and a cortex 3–4 cells thick, outer cells 4–8 µm in diameter and L/D 1–2. Rhodoplasts laminate, few per cell.
Reproduction: Sexual reproduction non-procarpic. Carpogonial branches (Fig. 154H) (2–) 3-celled, borne on mid medullary cells near apices of young segments, relatively straight and directed outwards, with a prominent trichogyne and sometimes with a sterile cell on the basal cell. Connecting filament single. Auxiliary cell a cell of one of the central filaments, producing a single gonimoblast initial towards the segment apex, later forming a branched fusion cell (Fig. 154H) (with a stalk) which cuts off radially chains of ovoid carposporangia 20–30 µm in diameter. Cystocarps swollen, 0.5–1 mm in diameter, stipitate; pericarp absent, cortex not or slightly thickened, with a slight ostiole. Spermatangia unknown.
Tetrasporangia (Fig. 154I) scattered (often dense) in the cortex of young segments, laterally to basally pit-connected, ovoid, 50–75 µm long and 30–45 µm in diameter.
Type from Sarawak, Borneo; holotype(?) in Herb. Zanardini, Museo Civico di Storia Naturale, Venice.
Selected specimens: Stony Point, Western Port, Vic., upper sublittoral on reef (Wollaston, 20.viii.1956; AD, A20554). Crawfish Rock, Westernport Bay, Vic., mid eulittoral, shaded (Womersley, 29.viii.1971; AD, A39449). Corinella, Westernport Bay, Vic., 2 m deep on jetty piles (AIMS-NCI, Q66C 3438-C, 14.ii.1990; AD, A60381). Carss Park, Georges R. Est., N.S.W., mid eulittoral (Womersley, 28.xii.1962; AD, A26432). S side Botany Bay, N.S.W., on Avicennia pneumatophores (Womersley, 23.i.1975; AD, A46058).
Distribution: Indo-pacific tropics; north island of New Zealand.
Westernport Bay, Vic., and Botany Bay, N.S.W., northwards, in calm situations often on mangroves or jetty piles.
Taxonomic notes: The type of C. opuntia var. elatior J. Agardh is a specimen of Harvey's Alg. Aust. Exsicc. 421L from Port Jackson, N,S.W., in Herb. Agardh, LD, 34243.
Although Catenella is usually regarded as uniaxial, at least in C. nipae there is a small group of apical cells (one often just protruding) from which the similar longitudinal medullary filaments are derived, and each cell of these filaments produces only one lateral.
AGARDH, J.G. (1876). Species Genera et Ordines Algarum. Vol. 3, Part 1 - Epicrisis systematis Floridearum, pp. i-vii, 1–724. (Weigel: Leipzig.)
DAVEY, A. & WOELKERLING, W.J. (1980). Studies on Australian mangrove algae. I. Victorian communities: Composition and geographic distribution. Proc. R. Soc. Vict. 91, 53–66.
HARVEY, W.H. (1863). Phycologia Australica. Vol. 5, Plates 241–300, synop., pp. i-lxxiii. (Reeve: London.)
KYLIN, H. (1932). Die Florideenordnung Gigartinales. Lunds Univ. Årsskr. N.F. Avd. 2, 28 (8), 1–88, Plates 1–28.
MIN-THEIN, U. & WOMERSLEY, H.B.S. (1976). Studies on southern Australian taxa of Solieriaceae, Rhabdoniaceae and Rhodophyllidaceae (Rhodophyta). Aust. J. Bot. 24, 1–166.
POST, E. (1936). Systematische und pflanzengeographische Notizen zur Bostrychia-Caloglossa Assoziation. Rev. Algol. 9, 1–84.
POST, E. (1964). Bostrychietum aus dem Nationalpark von Melbourne. Rev. Algol. (N.S.) 7, 242–255.
TSENG, C.K. (1942). Marine algae of Hong Kong, II: The genus Catenella. J. Wash. Acad. Sci. 32, 142–146.
ZANARDINI, G. (1872). Phycearum indicarum pugillus. Mem. R. 1st. Veneto Sci. Lett. Arti 17, 129–170, Plates 1–12.
The Marine Benthic Flora of Southern Australia Part IIIA complete list of references.
Womersley, H.B.S. (14 January, 1994)
The Marine Benthic Flora of Southern Australia
Rhodophyta. Part IIIA, Bangiophyceae and Florideophyceae (to Gigartinales)
Reproduced with permission from The Marine Benthic Flora of Southern Australia Part IIIA 1994, by H.B.S. Womersley. Australian Biological Resources Study, Canberra. Copyright Commonwealth of Australia.
Illustrations in Womersley Part IIIA, 1994: FIGS 154 G–L 156D.
Figure 154 enlarge
Fig. 154. A, B. Hypnea filiformis (A, AD, A19769; B, AD, A61512). A. Section of cortex with spermatangia. B. Transverse section of cortex with tetrasporangia. C. Hypnea ramentacea (AD, A42362). Section of cortex with spermatangia. D, E. Hypnea charoides (D, AD, A61582; E, AD, A60042). D. Section of cortex with spermatangia. E. Section of cortex with tetrasporangia. F. Hypnea valentiae (AD, A48965). Section of cortex with tetrasporangia. G–I. Catenella nipae (G, AD, A60381; H–I, AD, A26432). G. Habit of a tetrasporangial plant. H. Longitudinal section of apical segment with several carpogonial branches and a fusion cell producing gonimoblast initials. I. Longitudinal section of cortex with tetrasporangia. [H, I after Min-Thein & Womersley 1976.]
Figure 156 enlarge
Fig. 156. A–C. Hypnea valentiae (AD, A48965). A. Habit. B. Section of cystocarp with clusters of carposporangia. C. Branchlets with tetrasporangia] nemathecia. D. Catenella nipae (AD, A60381). Habit.
State Herbarium of South Australia