SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2405f2716e3182caa78d5079a3fa334cef0ab80acf144005c520fd7184bd72a8' 
  AND token = 'A4/6zASQUH3N+dRrVpzpO+1HaWRKWik/cMd+g43EHlA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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