SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0aef04602ed02bc23a8b7021b34d26cf048db386396eefc971a8c2f74a35c818' 
  AND token = 'ZSkfzRMhjEZzqceHxm9+mXg04cVNLn553g0WG44eVLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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