Dictyota acutiloba
Phaeophyta, Dictyotaceae
Authority: J. Agardh
Hawaiian name: limu alani
Characteristic feature: Flat, spirally twisted blades that branch in a Y pattern and lack a midrib.
Description: Plants erect, to 20 cm long, uniformly medium brown, axes and branches densely intertwined and spiraling conspicuously from base to apex when submerged; difficult to separate and spread out when out of water; mostly with repeated and dichotomous branching, becoming subdichotomous at apices, contributing to tufted branches distally and to antler-like appearance of tips; frond margins smooth. Single medullary cell layer and single cortical layer. Apices extending to acute tips, distance between subdichotomies in upper parts of fronds often unequal, one half of dichotomy twice as long as other half, longer continuing horizontally, and unequal branching providing 'antlers'; middle and lower frond dichotomies more equal and much longer, often twisted; tufts of hairs in centrally located irregular rows on both surfaces. Sporangia isolated or in small groups, irregularly scattered over both surfaces except near margins, 100-135 µm in diameter; oogonia in rounded to oblong sori near apices, antheridia indusiate, present in irregular or oblong sori, surrounded by multicellular paraphyses.
Habitat: Mid-intertidal pools to at least 55 m depth. Grows on rock and other algal species (epiphytic).
Hawaiian distribution: All main Hawaiian Islands, including the Northwestern Hawaiian Islands.
Other: Can be distinguished from Dictyota sandvicensis by the lack of small bladelets.