SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db7671cfa0625130abc9fe4fd1ee3426c4c0eb604de93505634c9e2bd367ab31' 
  AND token = 'OxkV4s7jTAnG1HHOYFwUYSLPL+9/Kr03lMIUMDcL7dU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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