SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9083f3c0b1c34b3b4f1b3aa49bb585b2b45201cdef315278e7c6a8860895f4fb' 
  AND token = 'Vn+xTcLiKVro/Y7G9SL3hLd/bPCMVc89p8DwVvqdAZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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