SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f1d7c21ffa35f351b7061d4bd01c33d5f61701125e57b65d0723561638473416' 
  AND token = 'xS1FfvvL0WGnYVo9cxn8rWtIqhDWb1QdC9i4EptMtxw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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