April 2013. A weed appeared in the Koror State Capital buildings and no one had seen it before. The largest plants are 30 cm tall, with leaves 5-7 cm long. The inflorescence is less and 1 cm in diameter. Uprooting the plants made the hands itchy, reminiscent of nettles.
There were a number of suggestions – Urtica dioica, sting nettle, Mercurialis perennis (Euphorbiaceae), before settling on Laportea interrupta.
It does have stinging hairs although most plants but perhaps not as well-armed as the common stinging nettles (Urticaspp.). It is considered native from SE Asia through Malesia into the Western Pacific and northern Australia, and is likely to be a native species in Palau. It tends to grow in semi-shaded sites associated with rainforest margins. In far north Queensland, it is quite common on well-vegetated uninhabited coral cays, so this might suggest avian dispersal.
The Queensland Herbarium has a specimen that may have been collected in Palau (is ‘Mutunlik’ in Palau) by J.F. Clarke in April 1953. There is plenty of information on this species on the internet e.g.:
L. interrupta has been collected in Chuuk, FSM, so it is likely to occur in Palau, too.