Craspedocarpus blepharicarpus (Harv.) Min-Thein & Womersley

Scientific Description

Habit and structure. Thallus erect, 5–10 cm high, complanately and subdichotomously to laterally branched with branches mostly 4–7 mm broad and 150–250 µm thick; branches uniform in width throughout the thallus, apices rounded, and with marginal fringes of simple, terete, proliferations 1–2 mm long and 300–700 µm in diameter. Holdfast discoid, epilithic. Structure uniaxial, the subapical cells each producing alternately two periaxial cells, the lateral ones developing the flat branch, and enlarging to form the alternately pinnate vein system (visible microscopically); medulla slight, cortex 2–3 cells thick with large ovoid inner cells and outer rosettes, the cells of which may divide and largely cover the inner cells in older branches, terete marginal proliferations with equally developed periaxial cells. Rhodoplasts discoid few to numerous per cell.

Reproduction. Sexual thalli probably dioecious; procarpic. Carpogonial branches 3(–4)-celled, borne on inner cortical cells in the marginal proliferations, lying almost parallel to the surface with outwardly directed trichogynes. Auxiliary cell adjacent and outward to the supporting cell, becoming darkly staining as do other adjacent cortical cells, and cells inward to the auxiliary cell producing small darkly staining nutritive cells. Gonimoblast initial formed inwardly, with later gonimoblast filaments radiating from a central group of cells, producing terminal chains of ovoid carposporangia 12–20 µm in diameter; sterile filaments fusing with pericarp cells, and also with the basal nutritive tissue. Cystocarps in the marginal proliferations, swollen, 450–700 µm in diameter, with a cortical pericarp, non-ostiolate. Spermatangia unknown. Tetrasporangia scattered in the cortex of the marginal proliferations, ovoid, 18–22 µm in diameter, zonately divided.

Distribution.Geraldton, W. Aust., to Phillip I., Vic., and Erith I., Bass Strait.

Habitat. C. blepharicarpus occurs mainly in moderate depths under slight to moderate water movement, commonly as an epiphyte on Amphibolis stems.

[After Womersley, Mar. Benthic Fl. Southern Australia IIIA: 421–423 (1994)]