Acanthophora spicifera (M. Vahl) Børgesen 1910

    Thalli 15 cm high, attached to substratum by a large irregularly lobed holdfast from which several erect axes arise. Thalli cartilaginous, sparingly branched or dense and bushy at the apex. Main axes solid, cylindrical, thick 0.6 – 2.2 mm wide without spines or scarce, with alternate or irregularly arranged indeterminate laterals and short determinate laterals. Determinate branches without constriction arranged spirally at the bases, 1- 3.5 mm long and 0.5-1.5mm wide with short spines; spines mostly found in the upper part of the determinate branches. Apex pyramidal, covered by short spines along with branched trichoblasts.

    Cross section of the thallus show a pentagonal central axial cell 205 - 340 µm long 190 - 230 µm broad surrounded by 5 distinct spherical pericentral cells , 210-280 µm diameter. Cortex made up of small, spherical cells, gradually reducing in size towards the periphery and measures 50-105 µm in diameter.