SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40ef109166c148fc6520f8b51fcf20d8ee722fd1769bb0c20cbf56a9af4c3148' 
  AND token = 'KRST1vk5dSXUMSHGhaWezGLuO7xo7jYJ1Qx917y47WQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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