SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce588dd7aaf363262aca59dbed835b381d78de33a6643b0c32157cae4948b719' 
  AND token = '01ZDupFe09sMN0+tEhdUkPp/pj4bh5QdSum69rELx5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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