SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98497b9329a23a07a2d657a67a65c0d39aad1f58c8641573cbb554b8b8acf224' 
  AND token = '/oom1EUMz0CNOtsbNHhVKGdx9c+Z3GQroc4WAwZQylo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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