SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a37ae157048f16e42b587232bf6d040e1ae952352edaa345e043580e0d88ae8' 
  AND token = 'vZncA1OuZtj/bB20upLD4eh8rkfB1wOeRug8EHREsvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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