Contarinia ventriglandis K.R.Dixon

Scientific Description

Habit and structure. Thallus reddish orange to bright orange, forming appressed spreading irregularly lobed blades to 2 cm wide which are easily removed from the substratum. Blades multiaxial; enlargedprimary axes absent; mesothallus not clearly defined. Medulla 80 –340 µm thick, composed ofradially directed filaments of large pale mostly elongate starch-filled cells 30–85 µm long and 10–30 µm diam. interspersed with secondary pit connections. Small rounded cells also occasionally cut off laterally from, or intercalary among, the larger medullary cells. Corticallayer present at the dorsal surface, absent ventrally, 25–65 µm and 3–5 cells thick, composed of deeply pigmented cells that gradually reduce in size to become 4–13 µm long and 2–8 µm diam. at the thallus surface. Vesicular cells orange, embedded within the middle to upper medulla, within the cortex and on the ventral surface, mostly terminating medullary filaments (rarely intercalary). Dorsal vesicular cells ovoid to acuminate, of various sizes, 30.90 µm long and 22–60 µm diam. Ventral vesicular cells rounded-cuboid to ovoid in radial vertical section, 12–45 µm long and 17–25 µm diam. Rhizoids to 325 µm long and 18 µm diam., multicellular, terminated by a multicellular digitate pad, occasionally with rounded vesicular cells borne laterally along their length.

Reproduction. Reproduction not seen.

Distribution. Western Australia.

Habitat. Epilithic and epizoic in shallow waters.

[After K.R. Dixon & J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 196 (2018)]