---

Dear Jan,
today I read your paper with a great interest. Thank you for your kind help.
I also discussed this matter with my friend Dr. Oleg Kosterin (Novosibirsk).
What we have?
1. Male licking presumably salt soil and drinking from presumably brackish pools, while females do not that, are very typical in Lepidoptera (you shortly mentioned it too).
2. Both Drosophylid and Lepidoptera are nectar/sap feeders.
3. You and Domenico Otranto supposed that Amiota & Phortica males produce a large amount of sperm. That is also typical for Lepidoptera.
Oleg offered a new explanation:
A very compact packing a lot of DNA in a lot of sperm nuclei requires a lot of cations like Mg++
Possibly that is why males of Amiota & Phortica specially need animal secretions, while females do not.