Sphaerococcus compressus:

Sphaerococcus compressus Agardh, Gracilariaceae: See Gracilaria bursa-pastoris (Gmel.) Silva.

Sphaerococcus helminthochorton:

Sphaerococcus helminthochorton (Schwend.) Agardh, Rhodomelaceae: See Alsidium helminthochorton (Schwend.) Kuetz.

Sphaerococcus lichenoides:

Sphaerococcus lichenoides C. Agardh, Gracilariaceae: See Hydropuntia edulis (S. G. Gmelin) Gurgel & Fredericq.

I have no articles for this botanical term, but there might be some for the next level down (if found).