Hello,
I am a PhD student working on the taxonomy and evolution of Hyacinthinae which includes Muscari.
This is a really interesting paper. The authors are working with Muscari s.lat., therefore recognise the genus Muscari to include X number of subgenera, as opposed to recognising those subgenera as genera.
What Böhnert et al. (2023) do is identify a new subgenus within Muscari s.lat., Pulchella. Pulchella is made up of species typically recognised as subgen. Muscari. In their study, the issue arises with the placement of these species in the subgen Leopoldia instead of the expected placement in subgen Muscari. Therefore, instead of rendering Leopoldia and Muscari as non-monophyletic and combining the two into subgen Muscari, the authors decided to name this group Pulchella, after the species Muscari pulchellum.
The option to lump or split the subgenera are both perfectly valid and is often down to personal opinion.
When you say ..." and argues that Pseudomuscari and Leopoldia should be combined into Muscari.", you are not technically wrong. But it is important to recognise what treatment of Muscari the authors are following in the first place. As they recognise Leopoldia etc as subgenera, then they are automatically part of the genus Muscari and not genera in their own right.
I really hope that makes sense! Always happy to chat more.
Best,
Hannah