May 2009. A plant sent from one of the outer islands of the Federated States of Micronesia.
Is definitely Sanchezia [ACANTHACEAE], probably Sanchezia parvibracteata, which spreads vegetatively on Rarotonga to a very limited extent. It is very similar to Sanchezia speciosa, which has not been seen to spread on Rarotonga.
There was also a suggestion that it was Sanchezia nobilis, but the flowers may be needed for confirmation. That species is not tthought to be invasive.