Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6fb83da87c2d3ce570ebff01bde1adb14969f1c6cda3b0eb4d6134d4bc93c18' 
  AND token = 'tlDzIDV+1ydYb/n8LOji3lFqu0D85B9dT36JmxSdx+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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