prickly seaweed

The geographical distribution of Acanthophora spicifera includes:

Guam Houtman Abrolhos Hawaii - non-indigenous. It was unintentionally introduced to Pearl Harbor, Hawai‘i from Guam in 1950 and has since become the most common nonindigenous algal species in the main Hawaiian Islands. On the west coast of Hawai‘i Island it has been documented at three sites, including Kaloko Fishpond in Kaloko-Honokohau National Historical Park, Pu'ukohola Heiau National Historic Site and Pu'uhonua o Honaunau National Historical Park.

Acanthophora spicifera is one of the most common nonindigenous algal species in Hawaii and it displaces many native species where it is abundant. The success of Acanthophora spicifera in invading benthic habitats is attributed to: (1) its ability to reproduce both sexually and vegetatively (by fragmentation); (2) successful epiphytism; and (3) its adaptability to a wide range of hydrological conditions. Rapid recolonization is probably due to the ability of Acanthophora spicifera to regrow from even small amounts of residual tissue and the high rate of reproduction. Algal abundance is influenced by both nutrient availability and herbivory. The combination of high nutrient concentration and low herbivory, as in Kaloko Fishpond, promotes greater increases in algal abundance than an increase in nutrients alone. Herbivory, therefore, appears to play an important role in preventing tropical macroalgal growth. Acanthophora spicifera is a palatable and highly preferred food for herbivorous fishes in Hawai‘i and has been found in the mouths of green sea turtles.

It has been proved by research workers that Acanthophora spicifera has significant cytotoxicity.