The sect. Diplolobus represents the Old World - Aristolochia distributed all across Southern Europe, Africa and Asia as far as to Australia.
Some dubious taxons are even known from Fidji, Vanuatu and Samoa which may represent independent species.
The section consists of 2 main clades,
Despite offering various extreme habitats and niches the subsect. Aristolochia apparently managed to conquer the whole Old World (except for southern Africa) with an outstanding diversity hotspot especially in Turkey and the Near East.
However, Podanthemum subsect. species are more restricted in their distribution range. More common throughout Africa there's not a single species of this subsection to be found in Europe and Near East.
They turn up in Pakistan again and diversify extremely towards the Malaysian Peninsula and especially Indonesia & The Philippines.
More than a dozen species have been described from there as new to science in the past 2 decades and at least the same number can still be expected possibly.
Many new species are currently leading a hidden existence although known to the public since respective research and revisions are yet missing.
Podanthemum subsect. species can easily be distinguished from subsect. Aristolochia species by the presence of a more or less short stipe between the utricle and the ovary.
To provide an easy overview the species' names below are assigned to their respective subsection & complex and linked with the subpages of the scroll-down menu on the right.