SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'baa37c93e9ac1e83550ab9abd007e3b90b9446540158ab92eccb7c19befed28f' 
  AND token = 'WXrFD/1a7wZ54aO1rqDx06dwK/sqhp0nEEhlQFXAsVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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