SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '96b1a6c34bd75efe61691b79e9e86d8bfd184393d9d98380c18003f3ec93ed8d' 
  AND token = 'c08ha2IaX7R36sN8uuX//pTx5MXlLVm06OZtTdgd7kA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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