SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9a2bef6e2f5af8806614a0e8fe5a83a9d4dc139755db7cb641ebd3f22a1618a' 
  AND token = '0FbIhIqpN6gQ9q0ULeN+Y83/OsDez9RD7eJBWReaXlg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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