SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ba242f72aa606abe589e1f767ea3e78c5ae57df3550af461cd5c254166676b0a' 
  AND token = 'mIAM5LODaNotrcL2WE6j35zCtEU2r7ELVrO3iC20VNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}