SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0ee55492f5a5c5416dbf6e347afbb7d351148dfa49445a32977335821bca08f8' 
  AND token = 'j4ZW8bKRxYwlgMgzIulmTHa0b39M9VLDe/+LMQc+6Ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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