SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae8c5c1e9cae28d435bfc81bfd7aae378cf8068104374c6564984a912377fae9' 
  AND token = 'WoK1/lnaCJFqsP4UM6eixwp8pi0eSRWN6ZYFpo5BXaw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}