SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '33a3287ad81cf8eede926b408a6ef767f3392bd73f239df2b98c7e5490febb5d' 
  AND token = '1sAdL5RGHe5WjfmgKf+nSkJ/jb79uczg/NWepRBhXAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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