Malakal Timonius (Timonius salsedoi)
The Malakal Timonius was described in 1987 based on material that had been collected in 1965 on the tiny island of Malakal in the Koror urban district of Palau, which is situated almost in the middle of the Palauan archipelago, and which consists of the three islands of Koror, Ngarakebesang and Malakal.
The species was not found since and the authors, while describing it, made the assumption that it might in fact have just been some sort of variant of another Palauan Timonius species.
C. Costion, a post doctoral research fellow on the department of Plant Biodiversity and Conservation Research, James Cook University in Queensland, Australia, had the opportunity in 2011 to undertake a field trip to the Koror urban district of Palau to search for this enigmatic plant species, and he actually found at least three Timonius species on the island, with two plants resembling the herbarium material.
The DNA of these two individuals was tested and they turned out to indeed be a distinct species.
The Malakal Timonius was rediscovered – but the whole population of this species consited of just two plants restricted to a single tiny island of less than 1 km² with only little remaining bits of native vegetation.
When C. Costion had the chance to revisit the island in 2014, he found the already small patches of remaining forests heavily destroyed with many of the larger trees fallen due to the typhoon Bopha that had hit the Palau Islands two years prior.
The Malakal Timonius this time was not found again, the last two plants had vanished, ensuring that this species is another entry to the ever-growing list of recently extirpated life forms. 
 F. R. Fosberg; Marie-Hélène Sachet: The genus Timonius (Rubiaceae) in the Palau Islands. micronesica 20(1-2): 157-164. 1987
 Craig M. Costion; W. John Kress; Darren M. Crayn: DNA barcodes confirm the taxonomic and conservation status of a species of tree on the brink of extinction in the Pacific. PLoS ONE 11(6): e0155118. 2016
 Craig M. Costion: Plant discovery and extinction: The narrow window. Plant Press 19(4). 2016