- Reference
- Mar.Benth.Fl.S.Australia 263 (1996)
- Conservation Code
- Not threatened
- Naturalised Status
- Native to Western Australia
- Name Status
- Current
Scientific Description
Habit and structure. Thallus encrusting or warty, up to 20 mm thick, epilithic or epizoic and affixed by cell adhesion. Structure pseudoparenchymatous; organisation dorsiventral; construction monomerous, consisting of a single system of branched filaments that collectively contribute to a ventrally situated core, and a peripheral region where portions of core filaments or their derivatives curve outwards towards the thallus surface; each filament composed of cells 2–11 µmin diameter and 2–25(–35) µmlong; a single epithallial cell terminating most filaments at the thallus surface, distal walls rounded or flattened but not flared; cells of adjacent filaments joined by cell-fusions, secondary pit-connections absent; trichocytes occurring commonly at thallus surface, arranged in vertical rows, horizontal fields or singly, not commonly becoming buried within the thallus.
Reproduction.Vegetative reproduction unknown. Gametangia, carposporangia and tetrasporangia produced in uniporate conceptacles; bisporangia unknown. Gametangial plants dioecious; carpogonia and spermatangia produced in separate conceptacles. Carpogonia terminating 3-celled filaments arising from the female conceptacle chamber floor. Mature female-carposporangial conceptacle roofs flush with surrounding thallus surface, composed of 4–6 cells above the chamber, conceptacle chambers 164–178 µm in diameter and 104–115 µm high. Carposporophytes developing within older female conceptacles after karyogamy, when mature composed of a large central fusion cell and gonimoblast filaments bearing terminal carposporangia, pore canals formed perpendicularly to thallus surface. Spermatangial filaments unbranched, arising from the floor of male conceptacle chambers, mature male conceptacle roofs flush with surrounding thallus surface, composed of 8–10 cells, conceptacle chambers 312–352 µm in diameter and 121–140 µm high. Tetrasporangial conceptacle roofs flush with surrounding thallus surface, 4–6 cells thick above the chamber, pore canals lined with non-protruding cells, conceptacle chambers 178–232 µm in diameter and 117–164 µm high; tetrasporangia usually occurring peripheral to a central columella, occasionally occurring across chamber floor, each mature sporangium (15–)27–61 µm in diameter and 45–85 µm long, zonately divided.
Distribution.Bahamas; Jamaica; various localities in the tropical and subtropical Western Atlantic and tropical W. Aust. In southern Australia, Lucky Bay, Cape Le Grand, W. Aust., to Point Westall, S. Aust.
[After Womersley, Mar. Benthic Fl. Southern Australia IIIB: 263–264 (1996)]