Halimeda tuna

On the other hand, association with more palatable seaweeds may have a negative impact on the chemically defended partner. For example, Halimeda specimens from Conch Reef, Florida Keys, with more than 50% of their thalli covered by Dictyota grow significantly slower than unepiphytized thalli (Beach et al. 2003). This study also verified that epiphytic Dictyota negatively affects metabolic rates of Halimeda tuna in part by shading their thalli, but probably also by chemical means, because the exposure to Dictyota-conditioned water elevated respiration rates in a manner similar to when H. tuna is naturally epiphytized by Dictyota. 

Koehn, F. E., Gunaserka, S. P., Niel, D. N., and Cross, S. S., Halitunal, an unusual diterpene aldehyde from the marine alga Halimeda tuna, Tetrahedron Lett., 32, 169, 1991. 

Halitunal (266) Alga, Halimeda tuna Coronavirus A59 Unknown [199]... 

Koehn, F.E. Gunasekera, S.P. Niel, D.N. Cross, S.S. Halitunal, an Unusual Diterpene Aldehyde from The Marine Alga Halimeda tuna. Tetrahedron Lett. 1991, 32, 169-172. 

Bosellia mimetical Halimeda tuna Gavagnin etal., 1994a... 

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