SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28f16b9f6266c138fbcc52d674853faa3ff9fd72f0bb04103e274b714bdc3184' 
  AND token = 'AYtINZMo7gYrUKliD8/B/FpGz5qTR6Em8cd4ACVRnDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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