SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '67ffb279f0410aa1b1b7a8a3b71e462fe5044e8010371ed57fe3bf27ef09deb3' 
  AND token = 'SFFu+7zF10Ic8mOsvhYBn05SYAl0MHQtndFGUJYI2vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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