Papilio s.l. is monophyletic, and Heraclides & Pterourus s.l. are monophyletic sister groups each containing several subclades which are themselves sister to most of the Old World Papilio taxa. There are also some Old World groups, Chilasa and Agehana, within Pterourus s.l. as discussed by Wu et al. (2015), although they regard Chilasa as sister to Pterourus rather than within it.

However, in my opinion, treating them all as separate genera, both from each other and Papilio, only hides the innate close relationship between the taxa when compared to other genera within Papilionidae. I feel that taxonomists need to be aware that splitting at genus level hides useful information for the non-expert end-users of the genus + species name we provide them with as a result of our analyses. Most ecologists etc etc who want to use the names in their own studies won't immediately know which species are closely related if they are overly split at genus level. I would prefer to regard them all as belonging to genus Papilio and use the relevant 'subgenus' name in parentheses after the genus name to provide more useful information. This is basically the approach adopted by Wu et al. (2015), who also treat all the species as belonging to genus Papilio, but there is a choice to be made between synomymising Agehana within Pterourus or keeping it as a separate subgenus and splitting the troilus and glaucus clades as separate subgenera.

Season's Greetings everyone,

Adam.

I agree, there is a lot of subjectivity about this type of classification and merging of species into each other

Hi, Avery,

I'm not a professional but have some collection of butterflies as spent a lot of in Indo-China and familiar with some reference on the problem in russian/ukrainian. For my opinion you should contact Dr. Alexander Monastirskiy from Russia who worked all his life in Vietnam and prepared perfect dissertation in zoogeographical distribution of butt. with a main attantion on Papilionidae (more than 60 sp. in this country). As well he is good in Indo-Mal. area in Gen. Paleozoogeography may help!

Address of diss.

https://www.dissercat.com/content/fauna-bulavousykh-cheshuekrylykh-lepidoptera-papilionoidea-vetnama-proiskhozhdenie-i-sovreme/read

Andrey

Dear Avery,

I recommend to read the publication of Wu et al. (2015) which indicates that Pterourus and Heraclides are distinct taxa based on molecular phylogentic analyses:

Wu L-W, Yen S-H, Lees DC, Lu C-C, Yang P-S, Hsu Y-F (2015) Phylogeny and Historical Biogeography of Asian Pterourus Butterflies (Lepidoptera: Papilionidae): A Case of Intercontinental Dispersal from North America to East Asia. PLoS ONE 10(10):e0140933.

Best wishes, Peter

https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0140933&type=printable

Not only useless to split but wrong......many papers were showing that Heraclides and even more Pterourus are not monophyletics. That collectors still use these infragenera is not really a problem but not anymore in any scientific publication.

Happy new year from Luc

Papilio s.l. is monophyletic, and Heraclides & Pterourus s.l. are monophyletic sister groups each containing several subclades which are themselves sister to most of the Old World Papilio taxa. There are also some Old World groups, Chilasa and Agehana, within Pterourus s.l. as discussed by Wu et al. (2015), although they regard Chilasa as sister to Pterourus rather than within it.

However, in my opinion, treating them all as separate genera, both from each other and Papilio, only hides the innate close relationship between the taxa when compared to other genera within Papilionidae. I feel that taxonomists need to be aware that splitting at genus level hides useful information for the non-expert end-users of the genus + species name we provide them with as a result of our analyses. Most ecologists etc etc who want to use the names in their own studies won't immediately know which species are closely related if they are overly split at genus level. I would prefer to regard them all as belonging to genus Papilio and use the relevant 'subgenus' name in parentheses after the genus name to provide more useful information. This is basically the approach adopted by Wu et al. (2015), who also treat all the species as belonging to genus Papilio, but there is a choice to be made between synomymising Agehana within Pterourus or keeping it as a separate subgenus and splitting the troilus and glaucus clades as separate subgenera.

Season's Greetings everyone,

Adam.

I'm agree with Adam, why splitting a clear monophylic genus into unclear subgenera. Heraclides subgenus is possibly valid but Pterourus clearly not. Considering the genetic distance between Heraclides and Papilio (s.l.) better to simplify and pool everybody as Papilio. Furthermore in the study of Wu were missing species such as the africans antimachus, zalmoxis or rex which are changing the topology of the whole tree.