SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f729def6071c70f4f0c724de1671444fb89238608e5108be456d73a57f093a59' 
  AND token = 'UbDMhzdK/0BQAEeqW0MX1Wlf+0kPkiycUWv29JIKl3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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