Chondria minutula Weber Bosse

Scientific Description

Habit and structure. Thallus to 18 mm tall, light red, with prostrate and erect axes, attached by clusters of rhizoids arising at intervals along the lower axes. Erect axes percurrent, laterally branched every 0.7–1.0 mm, with tapering apices and pointed tips. Trichoblasts borne near branch apices and in association with emergent lateral branches, dichotomously divided. Axes terete to compressed, near base 1.0–1.2 mm diam., tapering gradually distally to 200–300 µm diam. below apices, often with a slight bulge at branch primordia. Bases of lateral branches not or only slightly tapering, this more prominent in swollen branches bearing tetrasporangia. Cortical cells in surface view equidimensional near apices, becoming slightly longitudinally elongate in mid-thallus, to 10–20 µm diam. [L:B to 4], then equidimensional near the base.

Reproduction. Spermatangial plates forming on trichoblasts, as one branch of a lower dichotomy, oval to reniform, to 340 µm long and 440 µm wide, bordered by a single layer of sterile cells. Cystocarps on short lateral branches, spherical to urceolate, to 800 µm diam., with lachrymiform carpospores to 200 µm long and 100 µm wide. Tetrasporangia borne in a spiral pattern on lateral branches, spherical, tetrahedrally divided, 100–170 µm diam.

Distribution. Widespread in tropical waters of the Indo-Pacific.

Habitat. Epiphytic in the shallow subtidal.

[After J.M. Huisman in Algae of Australia: Marine Benthic Algae of North-western Australia, 2. Red Algae: 496 (2018)]