Botanical name: Suregada multiflora
Common names: False Lime, Limau Hantu
Family: Euphorbiaceae
Origin: Southeast Asia
Flowers are tiny, 5-8 mm across, male and female flowers separate on the same tree. Fruits resemble small limes (1-2cm), with three 'shoulders', green turning bright orange and splitting revealing the thin white pulp surrounding blackish brown seeds.
Link to this plant:
https://toptropicals.com/catalog/uid/suregada_multiflora.htm