SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e02f62112d368ba1cbad6d005d5158576fcdfadd39207ec0bed0a53bba5cd55c' 
  AND token = '4tJDVk6EIF4uBjZbc7ko1ETKNLsyyWGugFx4zrkc28E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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