SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c163ab5a05f79e01d33df42ef061e272e8d7544759d776dda3cfc4136de08e5' 
  AND token = 'viqX21wdvwGgFB+lhRrpyUnFtjfqKkDGuwJrFE3jixA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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