SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac8d30b87d4ccf447e51dc6a538484233bdc2d6914a9da3a3c2bbb0acf54cd61' 
  AND token = '39EC8HJwGWXBOwI7EvaPwJshbNIuUnD05vAdQOVc4U0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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