SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03f7561b5bafcb69d7cb6090128d064eee9af5bf18a1936ba095291ef18ab5d2' 
  AND token = 'GtqFzBeBDAQnj5blaqYJfG2sKvYwT5HVOdaTA0hLVO4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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