I slightly revised (removed a sentence from my comment above). Answers to Tobias’s questions are below.
“Cakkhunca paticca rupeca uppajjhati cakkhu vinnanam”
– ‘Rupa” or “rupayanata” involve external visual objects.
– “Cakkhu” or “cakkhayatana” requires cakkhu pasada rupa.
“Mananca paticca dhammeca uppajjhati mano vinnanam”
– “dhamma” or “dhammayatana” involve namagotta, kamma bija, etc and involve vinnana dhatu. Vinnana dhatu is present in all 31 realms.
– “mana” or “manayatana” is present when citta can arise.
With those fundamental facts, we can address Tobias’s questions.
1. In Asañña realm, only physical bodies (inert) with hadaya vatthu of those beings are present. Of course, dhammayatana is also present but those “dhamma” are prevented from contacting hadaya vatthu. Thus, manayatana is not present.
– Hadaya vatthu is in the bhavanga state. As I explained before, those are NOT bhavanga citta.
2. In arupa realms, only the manayatana and dhammayatana present.
3. Tobias’s final comment: I don’t see a problem with the following:
asanna satta – “Body only; no mind”
I may have misunderstood some questions. If so, ask again.