the pitcher exterior, but without blotches. The inner surface is yellow or green and may have reddish speckles. Upper pitchers are similar but often lack blotches, being a solid green, yellow, orange, or red, although reddish aerial traps occasionally do bear some darker markings. Sometimes upper pitchers may have a contrasting combination of colours in the form of a reddish pitcher body and yellow or green peristome, or vice versa. No infraspecific taxa of N. bellii have been described. Ecology Nepenthes bellii is endemic to the Philippines. It is common on Dinagat and northern Mindanao; its presence in southern Mindanao is "poorly documented" due to ongoing conflicts. As such, it is native to at least the provinces of Surigao del Norte and Surigao del Sur. It has an altitudinal distribution of 0–800 m above sea level. The species grows terrestrially in a number of habitats, including lowland heath forest, exposed sites such as cliff faces and landslides, lower montane forest among stunted vegetation, and disturbed or recovering secondary vegetation (such as previously logged dipterocarp forest). It also often colonises the sides of roads running through the forest. The known distribution of this species appears to roughly correlate with ultramafic substrate occurrence. Nepenthes bellii is often sympatric with N. merrilliana and N. mindanaoensis. Although N. bellii is known to form natural hybrids with both of these species, such crosses appear to be rare. Field observations of these three species suggest that they flower at different times of the year. Stewart McPherson considers the species "not currently threatened" and writes that it is "widespread" across Dinagat and northern Mindanao, where it is represented by "extensive stands". Nevertheless, habitat loss is affecting the species in lowland areas and this problem is particularly severe on Dinagat. Related species The combination of subglobular lower pitchers, densely fringed wings (often with clustered filaments) and proportionately long tendrils separate N. bellii from all other species with the possible exception of the miniature N. argentii. However, the latter species can hardly be confused with N. bellii as it does not produce a climbing stem, differs markedly in the shape of the lamina, and has a uniquely curved peristome that continues along the lower surface of the lid. Nepenthes bellii is closely allied to N. merrilliana and N. surigaoensis and shares with these species a similar morphology of the pitchers and laminae as well as a reddish colouration of