Note: this represents where the article stands relative to the Good Article criteria. Criteria marked are unassessed
Sorry for the delay in reviewing.
This article has a lot of issues that I can see on a quick skim.
The lead is far too short. Working
It relies far too much on the outdated account by Pocock, sources that old are usually only used for historical facts about taxonomy and for extinct species on Wikipedia.
Classification has uncited statements. Done
Doesn't actually provide much information about its systematics or evolution, especially considering that the paper it's cited to has quite a bit of detail.
Doesn't mention morphological differences between the subspecies, and the distribution already given would be better in a list form.
No info about breeding, except for one sentence in Description, oddly enough.
Description is poorly put together and doesn't really have a coherent flow (most articles have size, general appearance, sexual dimorphism, and then age related differences) Mostly fixed
Very little information on habitat considering what's available in the literature.
Distribution has too many statistics that should actually be in Conservation. Done
Half of Behaviour and ecology is just Pocock's account from 80 years ago, which is very outdated and should be replaced by more recent refs. Partly done, but I don't see anything necessarily wrong about using Pocock's account, it's not like these things change quickly.
Conservation also suffers from flow issues and just seems like a collection of random points with little connection between them.
Found an image of what I presume is a cub, and this would be better for the infobox imo. Partly done
Refs should italicise genus and specific names. Done
Indonesia WCS is not a scholarly source; fine at GA level, but would ideally be replaced by something better like a book or journal article.
I'll hold this for now, but this requires a lot of elbow grease, so I'd recommend letting this fail and renominating after you've addressed the points raised above. AryKun (talk) 11:54, 29 August 2023 (UTC)[reply]
so I'd recommend letting this fail and renominating. That makes sense, I guess. My apologies. Edward-Woodrow :) [talk] 12:10, 29 August 2023 (UTC)[reply]
All right, I'll fail this; if you want to work on this article and renominate, Mantled howler is a good example of what to aim for. AryKun (talk) 14:48, 29 August 2023 (UTC)[reply]