Materials and methods
The measurements and descriptions were based on freshly collected
materials. Multiple photographs were taken using Canon EOS 800D and
coloured plates were prepared and edited in Affinity Photo software.
Flowers were preserved in 70% ethanol and were subjected to
stereomicroscopy. The general plant descriptive terminology follows
Beentje (2016). Herbarium citations follow Index Herbariorum (Thiers
2023). Relevant specimens and literature of Thottea species from
the Philippines and neighbouring countries were examined in different
herbaria through high-resolution images from Global Plants on JSTOR
accessed at https://plants.jstor.org/ or Global Biodiversity Information
Facility (GBIF) accessed from https://www.gbif.org. An assessment of the
conservation status was carried out following IUCN (2022), based on our
current knowledge and using their terminology on categories, criteria
and subcriteria.