SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5c22b5d4556f1cd06dc5163b4349901d4902738a049687d76a0382a4f82733ea' 
  AND token = 'tqOjSfIEVos0l3LyzsN8PgGlbtTz+7Z2qfjk1rMJOCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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