according to "The Generic names of moths of the world" Vol.5, by D.S.Fletcher, 1984:

Maliarpha Ragonot, 1888 is a valid genus, type species separatella Ragonot, 1888
https://www.biodiversitylibrary.org/item/208731#page/106/mode/1up

Biafra Ragonot, 1888 is a valid genus, type species concinnella Ragonot, 1888
https://www.biodiversitylibrary.org/item/208731#page/41/mode/1up

if concinnella is not considered in the same genus as separatella, it is definitely Biafra concinnella

however, if it is considered to be in the same genus, the older genus name would have priority. Since they are both by the same year + author, the name published earlier in the paper will have priority, I believe. Biafra is on page 40, Maliarpha is on page 48. That means, also in this case, the genus Biafra wins!

The Ragonot 1888 publication is here https://www.biodiversitylibrary.org/item/204168#page/5/mode/1up
page 48 Maliarpha is correct and page 40 for Biafra is also correct

conclusion: regardless of taxonomic analysis, Biafra concinnella must be used ...

(additional discussion availble via @johanheyns who discussed it with Willy de Prins. Contact him if interested. Thanks)