SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8816b4f11ac20acd476827ea5fe18a312ec0e483676e933c9c528b56fb98454d' 
  AND token = 'YyFnnzgetpmBZwQDuhiQ6E/BT42wX5MHtqSQR6sEz+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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