SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7da2cd26dd28e323cef3fac177fcbae24a4cb5f40fe75dff40e137da01e237e7' 
  AND token = 'aFr3bvjy2WvFpvAKyeucnY2SzSVwyJY4KufHeOYmn7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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