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What is meant by "crippled legs"? Is this vandalism? Drutt (talk) 20:59, 4 June 2008 (UTC)


How long can isopoda live without food?

A 2015 Shark Week episode says "years", though I find that hard to believe. WilliamSommerwerck (talk) 00:14, 10 July 2015 (UTC)

In Pop Culture[edit]

"alliance with the ocean horror"
Just a little tidbit for people working on the page, I don't think this should ever be in the article.

I also have a little tidbit of isopods in popular culture. In recent strips of Questionable Content, the character Faye has been wearing an isopod shirt that reads "I feel pretty," as seen in this strip. Jeph Jacques has also announced on his LiveJournal that the shirt will soon be available for pre-order. Wasn't sure if this stuff was actually pertinent to the article, so I didn't want to add it myself. Take it and use it as you will, if at all. -- 14:03, 27 September 2007 (UTC)
Mentioned on the Giant isopod page. Drutt (talk) 21:02, 4 June 2008 (UTC)

Ummm, I dunno how this works, but.... —Preceding unsigned comment added by (talk) 23:46, 5 April 2010 (UTC)

At least in Charles Stross' novels (well, one of them that I can think of - The Apocalypse Codex), there's a connection between isopods and his version of various Lovecraftian horrors; don't know if Lovecraft had anything isopod-ish in his own fiction, though "the ocean horror" above might be a reference to that. Schissel | Sound the Note! 22:24, 9 November 2013 (UTC)

I believe that one of the "recent" Godzilla films has isopods accompanying Godzilla. WilliamSommerwerck (talk) 00:21, 10 July 2015 (UTC)


"Isopods are an order of fearless peracarid crustaceans" — fearless? —Preceding unsigned comment added by (talk) 21:51, 17 August 2010 (UTC)

GA Review[edit]

This review is transcluded from Talk:Isopoda/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Sunrise (talk · contribs) 03:16, 3 June 2014 (UTC)

I will start this review soon. Sunrise (talk) 03:16, 3 June 2014 (UTC)

I’m now posting my first set of thoughts. I’ll probably add more every couple of days until I’ve gone through everything; I’m not following any particular order and may or may not finish my evaluation of any one of the criteria at any given time. :-)

Also, since I will be citing the scientific literature (which, as you probably know, can be quite dense), please let me know if I can help you by summarizing. If you don’t have access to particular sources, I can summarize those as well or supply you with copies. Sunrise (talk) 06:11, 4 June 2014 (UTC)


YesY Section complete. Sunrise (talk) 05:30, 13 July 2014 (UTC)

  • Green tickY Habitat (marine/freshwater/land) is described twice in the lead.
  • Green tickY Wording along the lines of “Many isopods are X but some are also Y or Z” can be more concisely written as “Isopods may be X, Y, or Z.” (The second formulation is also less vague.) For example, from the first paragraph: “many are scavengers...” and “a large proportion in the sea...”
Done. Cwmhiraeth (talk) 10:44, 10 June 2014 (UTC)
Looks good. I think there might have been one other occurrence of this, but I don't see it so probably it was changed during unrelated editing. Sunrise (talk) 01:51, 11 June 2014 (UTC)
  • Green tickY Diversity and classification: “Around 10,215…” This is a very precise number; it’s a bit jarring to see it combined with a word that you typically see with less precise estimates. I also note that the source has updated to 10,290 since this was added; maybe “over 10,000” would be sufficient, or you could use an “As of [date]” formulation.
  • Green tickY The lead needs to better summarize the body. For example, the classification is not mentioned in the lead; by contrast, the fossil record is mentioned in the lead but not in the body. (You may want to hold off on this since it will need to account for changes in the article.)
Done. Cwmhiraeth (talk) 10:44, 10 June 2014 (UTC)
Looks good. Sunrise (talk) 01:51, 11 June 2014 (UTC)
  • Green tickY Description: there are two references to gills in this section, but presumably these statements would only be relevant when talking about the aquatic species.
  • Green tickY There is a third reference to gills in the “Adaptations for life on land” section, which appears to refer to “desert species.” Do the terrestrial species have structures that are called gills? If so, I think this should be clarified somewhere.
For these two points, I still think there could be further clarification, since for most people gills are something you only find in the sea. For example, a search for "terrestrial isopod gills" gives this, which seems like a reasonable source to use. Sunrise (talk) 05:18, 5 June 2014 (UTC)
  • Green tickY Reproduction and development: when I first read the last sentence, I interpreted it as saying that other crustaceans do not moult - I think this is due to the parenthetical statement that induces a pause at "exoskeletons."
  • Green tickY The final sentence (most successful group of terrestrial crustaceans) doesn't feel like it flows well from the previous sentence. For example, maybe an intermediate statement describing a few of the major groups could help here.
  • Green tickY The lead mentions woodlice in two different places. Is there any way to bring them together? I’m guessing that you want to begin and end the lead with statements that help draw the reader in, though, so I think this probably isn't a big issue.
I have dealt with most of these points and will work further on the lead when the body of the text is sorted. Cwmhiraeth (talk) 11:12, 4 June 2014 (UTC)
  • Green tickY Locomotion: removing "some of which are pelagic" may improve clarity.
  • Green tickY "Woodlice are the most successful group of terrestrial crustaceans" is now in the article twice (you copied it from the lead to the body, but it was already in the body).
  • Green tickY Reproduction and development: "brooded in the brood chamber" – is there a way to avoid the repetition?
  • Green tickY Adaptations for life on land: "They do this by living in a humid environment, under stones, bark or debris or hidden in leaf litter" – tense mismatch.
  • Green tickY Adaptations for life on land: "Members of the families Ligiidae and Tylidae...are the least specialised for life on land." I'm guessing that this means the least specialised among woodlice (since the least specialized among all isopods would really be the species that are completely aquatic), but the last mention of woodlice was at the beginning of the paragraph.
I have dealt with these points and have expanded the part about respiration in terrestrial species. The respiratory organs are still called gills according to my source. Is it clear enough now? Cwmhiraeth (talk) 10:42, 5 June 2014 (UTC)
I was thinking that a reader may be confused by a mention of gills on a terrestrial organism; I didn't mean to suggest that it was the wrong term. My own preference would be to include an explicit statement (maybe up in the Description section where gills are first mentioned) that the respiratory structures of terrestrial isopods are still called gills. That said, I see that the Gill article prominently mentions respiration on land, so I'll mark this as resolved. If you decide to add more on this, a wikilink to that article might also be useful.
Wikilinked. Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
On the previous point ("least specialised"), I don't think I was clear enough myself. :-) The new phrasing still allows the sentence to be interpreted as saying that these two families are the least specialized among all isopods, not just among the woodlice. One way to address this might be a formulation such as "Among the woodlice, the families..." Sunrise (talk) 05:22, 7 June 2014 (UTC)
Done. Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
  • Green tickY Pereopod redirects to Decapod anatomy, but isopods are not decapods. I assume this might be a problem with the redirect?
See below. Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
  • Green tickY Paragraph 1 of the description introduces the fact that the abdomen is formed from six segments, but paragraph 3 introduces it again as if it’s new. I think the second occurrence should use a construction that assumes the fact has already been introduced (like “The six segments of the abdomen are…”)
Done. Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
I see that your rewording has been reverted as inadvertently introducing an inaccuracy; is there a better option? If not, I'm not going to fail this article based on a copyediting issue. :-) Sunrise (talk) 01:51, 11 June 2014 (UTC)
I clarified the usage to introduce a mention of segment fusion in the first paragraph, and reworded the third paragraph so it wasn't another introduction of the anatomy. Esoxidtalkcontribs 03:18, 11 June 2014 (UTC)
  • Green tickY Similarly, the article introduces the fact that some isopods are parasitic twice: once in paragraph 2 of "Diversity and Classification" and once in paragraph 2 of "Feeding and Nutrition." This one is trickier since I’m not sure how the second occurrence could be reworded. I’ll make it optional.
Rephrased the second mention because I thought a "parasitic lifestyle" a bit "jargony". Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
  • Green tickY Could you add a brief explanation for the term "pleopod"? (Or a wikilink, but I see it redirects to Decapod anatomy so it's the same issue as above.)
I have done this, but actually, the Decapod anatomy page would be better renamed "Crustacean anatomy". Cwmhiraeth (talk) 13:19, 7 June 2014 (UTC)
I edited the parenthetical to "swimming limb", which is what I believe you meant, but that's a better descriptor for amphipods than isopods in my opinion. In isopods the pleopods are lamellae that can serve as both gas exchange and some propulsion in the marine species. In terrestrial species, they would only serve as gas exchange. They can also be modified in males as a gonopod. Esoxidtalkcontribs 22:44, 7 June 2014 (UTC)
Thank you Esox for your comments and improvements to the article. Cwmhiraeth (talk) 06:26, 8 June 2014 (UTC)
Agreed. :-) Sunrise (talk) 01:51, 11 June 2014 (UTC)
  • Green tickY In a couple of cases, the article doesn't clarify the distinction between number of species and number of individuals.
-"few members of this formerly widespread suborder remain"[1] Of course, this may be correct (and I find it highly likely), but the source only talks about a great reduction in their range, not that the number of species has actually declined.
Done. Cwmhiraeth (talk) 12:40, 14 June 2014 (UTC)
-"the increase in abundance of marine fish"[1] The source describes an adaptive radiation, which refers to number of species, while abundance refers to number of individuals.
Done. Cwmhiraeth (talk) 12:40, 14 June 2014 (UTC)
Looks good. I might suggest using "predation" rather than "challenge" for the marine fish, as "challenge" on its own is a bit vague. Sunrise (talk) 18:21, 14 June 2014 (UTC)
I was actually looking at that earlier, but hesitated to have predator used twice in that sentence, but I think it's unavoidable. Changed it to predatory pressure. Esoxidtalkcontribs 21:33, 14 June 2014 (UTC)

Sorry for the delay – real life intervened. I’ve read through the article again to look over the changes since my first check of criterion 1. After this set, I’ll check to make sure I haven't missed anything from the criteria, and then we’ll be done. :-) Sunrise (talk) 06:33, 9 July 2014 (UTC)

  • Green tickY"Some species can roll themselves into a ball" – the context in the lead is unclear. For most of the facts in the lead, it’s clear why they are important to a general overview of the subject, but this one feels out of place. I would either leave it out or briefly specify its importance (that it is one of the adaptations to terrestrial habitats).
Done. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
  • Green tickY"Adaptations for life on land" may not be the best section title, since the section now has a broader scope than this. Maybe something like “Terrestrial isopods”?
Changed. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
  • Green tickYIn the discussion of terrestrial isopods, "enhancing the activity of microbes" is supposed to be a subset of "aiding in the decomposition of plant material." The source gives two mechanisms by which isopods aid in decomposition, the other being "mechanical and chemical breakdown of plant litter."
Done. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
I think this change wasn't quite right, so I adjusted it slightly ("thus" -> "and by") to what I think the source is saying. Sunrise (talk) 05:15, 13 July 2014 (UTC)
  • Green tickY"spotted rose snapper fish" – I think "fish" is usually left out in this case. I imagine you probably put this in for clarity, so I'll just point this out and let you decide.
Done. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)

Verifiable with no OR[edit]

YesY Section complete. Sunrise (talk) 05:16, 13 July 2014 (UTC)


  • Green tickY "Isopods are typically flattened dorsoventrally..."[2][3] The source says "Isopods are thought of as dorsoventrally flattened, as in the typical terrestrial slater, and indeed many species fit this morphological stereotype." It seems to me that they're saying something like "the most recognizable isopods are dorsoventrally flattened, and in fact many of them are" but I don't think this makes the case for "typically."
"and indeed many species fit this morphological stereotype" to me reads like an assertion that the dorsoventrally compressed body type is typical. That is the typical body form, only a few families have rounded bodies. I added another source. Esoxidtalkcontribs 01:31, 13 June 2014 (UTC)
Thanks! For me, "typically" corresponds more with "most" than with "many," but I do recognize this is subjective. (And there is also that Cwmhiraeth pointed out that it's in the Ruppert source.) Sunrise (talk) 09:33, 14 June 2014 (UTC)
  • Green tickY "This means that the gills, which in other related groups are protected by the carapace, are relocated to specialised limbs on the abdomen."[2][3] The source says "Because they lack a carapace, the gills, which are covered by the carapace in other groups, are absent, so they breathe using specialised lamellar gill-like pleopods ("swimming limbs") on the posterior section of the body." (Note "relocated" vs "absent.") We already discussed this topic, but I'm not sure how best to represent this source.
I think the use by the source of the word "absent" is poor. If they had no gills they would die. Cwmhiraeth (talk) 05:57, 12 June 2014 (UTC)
They serve as gas exchange, and are referred to as both gills, and gill-like structures by different sources. This is another structure which may or may not fit the formal definition of a gill. Some sources refer to them as gills, some as "gills" or gill-like, and some more descriptively, as modified lammellae that serve as gills. I think the last one is better, since they aren't the typical gills that fish, decapods, and even bivalves have. I think I can give the description section some attention for more clarity, and use the correct terms. It seems to use terms for crustacea, for example thorax, abdomen, etc. Cephalon is the head region, not cephalothorax, and the "thoracic" (pereon) segments are referred to as pereonites (segments of the pereon), pleonites are segments of the pleon. I'll find a diagram which would be useful for the page. Esoxidtalkcontribs 00:42, 13 June 2014 (UTC)
It is very useful having your help with the correct terms. Thank you. Cwmhiraeth (talk) 11:15, 13 June 2014 (UTC)
  • Just noting that I don't have access to citation 4 (Ruppert). I might be able to find it at the library later.
  • Green tickY "One or more of the abdominal segments, starting with the sixth segment, is fused to the telson (terminal appendage) to form a rigid pleotelson."[4] Could you cite a page number for this so I can check it? Searching for keywords gives a lot of results.
I removed this source. Cwmhiraeth (talk) 05:57, 12 June 2014 (UTC)
It had taxonomic descriptions of genera, whose body types have fusions of 1 segment to 6 segments, it was a suitable source. For a succinct description refer to the glossary, page 129 for a description of the pleotelson. I will re-add it and an additional source for ones which mainly have 6 segments fused, and others which have 5 fused. Esoxidtalkcontribs 00:42, 13 June 2014 (UTC)
  • Green tickY "The first five segments each bear a pair of biramous pleopods (lamellar structures serving the function of gas exchange, and in aquatic species as gills and propulsion)"[5] I don't see this in the source - I think there was a mixup where a citation to the Tree of Life was intended. The statement will also need a citation for the description of pleopods as lamellar.
I added that source for the part about serving as gas exchange and propulsion. I'll add one for the description as lamellar, as well as a general description of the pleopods. Esoxidtalkcontribs 00:42, 13 June 2014 (UTC)
Looks good. I adjusted the Wilson reference slightly since the chapter name was linked to a Wikipedia page (if you're not aware, there are automatic Wikipedia reference generators at WP:Citation tools - I usually use the Google Books tool to fill in the cite book template). Sunrise (talk) 09:33, 14 June 2014 (UTC)
Thanks for fixing that. I use wikiEd and refToolbar, and I believe with that one I used the autogenerate feature from the ISBN. I'll have to double check which fields are used when doing that for books. Esoxidtalkcontribs 13:25, 14 June 2014 (UTC)
  • Green tickY "...are readily visible on the underside of a woodlouse."[2] I don't see this in the source.
I have made some alterations to the referencing as a result of these comments. Most of the points you are raising above could be solved by putting all the references at the end of the paragraph. For example, my basic source is Ruppert. In paragraph one the "typically dorso-ventrally flattened" comes from Ruppert, but he does not mention the term "cephalic shield". Then again, you read around a subject as you work on it, and the statement that the woodlice' "lungs" are readily visible came from somewhere but I now know not where, so I have removed it. Cwmhiraeth (talk) 05:57, 12 June 2014 (UTC)
Yeah, I've done that sort of thing too. :-) GA doesn't require specific citation formats, of course, so just let me know if I end up asking for something that's actually from Ruppert. Sunrise (talk) 09:33, 14 June 2014 (UTC)

Diversity and classification[edit]

  • Green tickY "The largest isopods are in the genus Bathynomus"[6] Perhaps a bit trivial, especially for a group referred to collectively as the "giant isopods," but the source only says that Bathynomus giganteus is the largest isopod (singular) and doesn't refer to other members of the genus. So "The largest isopod is in the genus Bathynomus" or "The largest isopod is Bathynomus giganteus" would work. (The second half of the sentence is verified for giant isopods in general but not B. giganteus, so a rewording may help.)
Done. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)
  • Green tickY "In marine and reef aquariums, parasitic isopods can become a pest, endangering both the fish and the aquarium keepers."[7] Two things: the source only seems to discuss reef aquariums, so I don't think "marine" is supported here; and the source establishes that isopods may injure aquarium keepers, but I'm not sure "endanger" is the right description since to me that implies serious injury or death.
Done. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)
  • Green tickY "The World Marine, Freshwater and Terrestrial Isopod Crustaceans database subdivides the order into eleven suborders"[8] I haven't used this database before, so I may be interpreting it incorrectly, but it appears to include a 12th accepted suborder ("Isopoda incertae sedis"). Esoxid could you perhaps comment on this? :-)
This does not refer to another suborder, but to some species whose classification is unclear. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)
Correct, it just means uncertain placement, so there are either conflicts on where to place them, inconclusive research, or none at all. So only 11 accepted suborders. Esoxidtalkcontribs 01:37, 13 June 2014 (UTC)
Makes sense. Sunrise (talk) 09:33, 14 June 2014 (UTC)
  • Green tickY "Cymothoida - Suborder of almost entirely marine isopods."[9] I don't see "almost entirely marine" in the source. It says that most Gnathiidae and Corallanidae are marine, but e.g. Cymothoidae is just described as "both marine and freshwater." The description of the largest individual family (Bopyroidea) doesn't have any mention of habitat.
Done. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)
  • Green tickY "Oniscidea - Suborder of semi-terrestrial and terrestrial isopods fully adapted for life on land."[10] I don't think the source supports "semi-terrestrial." (Also, it wouldn't make sense to then call them "fully adapted for life on land"!) The article does say that Ligiidae and Tylidae inhabit the splash zone, but doesn't call them partially aquatic.
Done. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)
  • Green tickY "Sphaeromatidea - ...This suborder now includes part of the formerly recognised suborder Flabellifera." The source only describes a proposal, saying "Two suborders, Cymothoida and Sphaeromatidea, have been proposed as replacement taxa for the Flabellifera" - I think this was in another source so I think it's correct, just needing a different citation.
Done. Cwmhiraeth (talk) 06:30, 12 June 2014 (UTC)

Evolutionary history[edit]

  • Green tickY "these form relic populations in freshwater environments in the southern hemisphere."[1] The source describes them as having a Gondwanan distribution - Gondwana included regions that are now in the northern hemisphere, namely India and parts of Africa and South America.
Done. Cwmhiraeth (talk) 12:40, 14 June 2014 (UTC)
  • Green tickY "The long-tailed isopods...[have] uropods which can be used as a rudder."[1] The source says the uropods "provide hydrodynamic planar surfaces to assist in swimming" which I don't think is the same thing - for example, it might refer to appendages used for paddling, or to reduce friction generated by the flow of water past their body.
Done. Cwmhiraeth (talk) 12:40, 14 June 2014 (UTC)
  • Green tickY "Isopods in the suborder Asellota are by far the most abundant and speciose group of deep sea macrofauna."[1] The source says, "Hessler and Wilson (1983) calculated that 32-51% of all benthic species taken in all deep-sea samples, anywhere in the world have been peracarids, and of the peracarids the isopods are by far the most abundant and speciose deep-sea group" (and "about 90 percent of all described isopods from [the deep sea] are asellotans"), but I don't think this is sufficient to support the statement. "Most abundant and speciose" is describing the isopods relative to the peracarids (not the asellotans relative to all macrofauna).
Done. Cwmhiraeth (talk) 12:40, 14 June 2014 (UTC)
Since you're now describing asellotans relative to isopods, I might remove the term "abundant" as well, since it's ambiguous whether the source supports that. Sunrise (talk) 18:21, 14 June 2014 (UTC)
Indeed. Cwmhiraeth (talk) 19:43, 14 June 2014 (UTC)


  • No entries for this section.

Feeding and nutrition[edit]

  • Green tickY"The majority of isopods are scavengers, browsers, but some are predators, parasites and filter feeders."[11][12] I think you mean "scavengers and browsers," but I can't find this in either source. The term "browse" is only found in the first source and is limited to describing some members of Sphaeromatidea and Valvifera.
The PLoS source, which is isolated to marine groups, mentions four feeding types for all marine isopods, in the section titled Feeding: "Although it is remarkable how few studies have directed research at feeding modes, four broad categories can be recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. [...] Carnivorous feeders can be further split into three groups—micropredators, predators and scavengers." The section used to mention omnivores in place of browsers. I don't agree it should be scavengers and browsers, since some are limited to browsing on algae, or the Bathynomus that it mentions. It should actually be detritivores and browsers. The second source, for terrestrial groups, on page 211 under the Feeding habits section groups several feeding types into omnivory: "Isopods are detritophagous and omnivorous animals feeding on live and dead leaves, fungi, or live or dead animals." Esoxidtalkcontribs 21:02, 19 June 2014 (UTC)
Sorry, I wasn't clear. The main issue is that the sources need to support describing the first two categories (now detritivores and browsers) as the majority. But for example, I think a statement like "Marine isopods may be [four categories] while terrestrial isopods may be [two categories]" would be supported. Sunrise (talk) 05:27, 20 June 2014 (UTC)
I see what you mean now. I'll rework that section. Omnivory used to lump just about everything into that group, so I'll just make a distinction that parasitic and filter feeding forms are for aquatic species. Esoxidtalkcontribs 21:35, 20 June 2014 (UTC)
Looks good. I've never seen the use of "occupying a feeding habit" before - I presume the meaning is analogous to occupying a niche? Sunrise (talk) 23:52, 22 June 2014 (UTC)
Correct. Esoxidtalkcontribs 00:51, 23 June 2014 (UTC)
  • Green tickY"Parasitic species are mostly external parasites of fish and feed on blood. The larvae of the Gnathiidae family and adults cymothoidids have piercing and sucking mouthparts and clawed limbs adapted for clinging onto their hosts.[13] I'm guessing that this is from Ruppert?
Done. This paragraph is quite complex because the article uses the up-to-date WoRMS classification while Ruppert and much of the literature uses older classification systems. Cwmhiraeth (talk) 10:09, 20 June 2014 (UTC)
Done. Cwmhiraeth (talk) 10:09, 20 June 2014 (UTC)
If you were a blood-sucking parasite, would you choose the outer surface of a barnacle? ;-) Cwmhiraeth (talk) 06:34, 20 June 2014 (UTC)
True. :-) Sunrise (talk) 23:52, 22 June 2014 (UTC)
  • Green tickY"bopyrids, living under the carapace of shrimps and crabs"[16] The source says "in the gill cavity or on the carapace" rather than "under the carapace."
Done. Cwmhiraeth (talk) 10:09, 20 June 2014 (UTC)
Many of these examples came from Ruppert where there is a figure showing diverse lifestyles of parasitic isopods. I have added an extra reference. Cwmhiraeth (talk) 06:34, 20 June 2014 (UTC)
  • Green tickY"it eats the tongue of the fish"[17] - the source only says "causes the degeneration of most of the tongue". According to Cymothoa exigua, the tongue is not eaten.
Done. Cwmhiraeth (talk) 09:34, 20 June 2014 (UTC)
  • Green tickY"the only known instance of a parasite functionally replacing a host structure."[18] The source specifies "in animals," and doesn't say "only known" but rather "first known" (and it's fairly weak since it's preceded by "we hypothesize that"). This article is also directly referred to by the Tree of Life source, but they speak much more narrowly, and don't commit to whether the isopod functionally replaces the tongue.
This sentence precedes my involvement with the article. I have added some qualifying words. Cwmhiraeth (talk) 09:34, 20 June 2014 (UTC)
I added "in animals" as well since you may have missed that. :-) Sunrise (talk) 23:52, 22 June 2014 (UTC)
  • Green tickY"Food is sucked into the oesophagus and passes into the stomach where hydrolysis takes place and the material is processed and sorted." This is one of the statements I can’t check the sourcing for, but the terminology doesn't feel right. Could you check the specific terms used in the source? These comments are based on my general knowledge of the digestive process in animals, not anything specific to isopods, so please let me know if I’m wrong. Specifically:
- the esophagus works by peristalsis, not by suction.
- hydrolysis is part of the processing, but in the article it seems to be presented as separate.
- processing (which I assume to be synonymous to digestion here) is implied to happen exclusively in the stomach, but typically it includes all steps in food breakdown, including e.g. the enzymes in saliva that start working when the food is still in the mouth.
I've rephrased this section while referring to the source which does not mention any digestive processes before the food reaches the stomach. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
Looks good. :-) Sunrise (talk) 05:15, 13 July 2014 (UTC)
- I’m not sure about the use of the term "sorted," since I think all the processed components should end up in the circulatory system.
Sorted into nutritious and indigestible components Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
This is one where I'd have to agree that the use of "sorted" would imply a mechanical or deliberate separation that would occur outside of the gut, like in bivalves. Digestion in isopods may involve filtering of solid particles and fluids in the proventricular and digestion/absorption of fluids in the hepatopancreas caecae, some of which is transferred back into the foregut to aid in digestion, but I'm not aware of any active sorting that happens. Describing sorting in the way it is used in the article is just describing digestion, where food is digested and absorbed, and indigestible material is egested. "Filtered" would be fine, but I don't think "sorted" is. Esoxidtalkcontribs 20:56, 10 July 2014 (UTC)
What the source actually says is "The posterior end of the foregut is the stomach, where trituration, hydrolysis, and sorting occur." Cwmhiraeth (talk) 04:59, 11 July 2014 (UTC)
I can't speak to the intended use of the word, but based on my knowledge of their internal anatomy it sounds like that usage is referring to the separation of fluid and solid material by means of the filtration that occurs in the proventricular. In the context of this wiki article I'd suggest it not use sorting, which would imply selective separation of indigestible, or less nutritious food particles. What do you think Cwmhiraeth? Esoxidtalkcontribs 20:44, 11 July 2014 (UTC)
I have changed the word to "filtered". Cwmhiraeth (talk) 05:49, 12 July 2014 (UTC)

Reproduction and development[edit]

  • Green tickY"Some Cymothoidans are protandrous hermaphrodites, and some Anthuroideans are the reverse, being protogynous hermaphrodites."[11] I'm confused by the terminology here. I think that "protandry" refers to either male to female or male to hermaphrodite, and "protandrous hermaphrodite" refers specifically to a male-to-hermaphrodite species, but that in both cases it would still be referred to as sequential hermaphroditism. (Same idea for protogyny.) In this case that would mean the source only supports use of "protandry" and "protogyny."
I have added the word "sequential". Does that solve the problem? Cwmhiraeth (talk) 10:35, 20 June 2014 (UTC)
I think the issue is made unclear from referring to the wiki page for sequential hermaphroditism. When it uses the phrase "female to hermaphrodite (protogynous hermaphroditism)" it needs to specify it being simultaneous, although I have never heard of female to hermaphrodite. If you refer to the main wiki for hermaphroditism it does not mention female to hermaphrodite, and I have found nothing in any of my zoological reference material so I do not believe that is accurate. In this context both protandry and protogyny are referring to sequential sex changes, so "protandrous hermaphrodite" (and protogynous) is accurate in my view since that already refers to a form of sequential hermaphroditism. Esoxidtalkcontribs 21:33, 20 June 2014 (UTC)
That might explain why I had a hard time looking this up. :-) Okay, so then I understand that "protandrous hermaphrodite" and "protandrous" mean the same thing - should this edit be changed back or does the new version work? Sunrise (talk) 23:52, 22 June 2014 (UTC)
I'll just remove the added "sequential", as it's redundant. Esoxidtalkcontribs 00:57, 23 June 2014 (UTC)
  • Green tickY"The eggs hatch as mancae, a post-larval stage"[1] "Post-larval" doesn't seem to be supported. (I don't think it's correct either - as the first life stage after the egg, they would be the larvae.)
As I understand it, considerable development takes place in the egg before hatching and the larval stage is bypassed. Ruppert states: "... and the hatching stage is a manca postlarva." Cwmhiraeth (talk) 10:35, 20 June 2014 (UTC)
Mancae are a developed stage of crustaceans, which undergoes larval development within the egg. I agree "post-larval" is a bit confusing, but it is described as a post-larval stage. See Moore, R. C., and L. McCormick. 1969. General features of Crustacea. In: R. C. Moore (ed.), Treatise on Invertebrate Paleontology, Part R, Arthropoda 4. Geological Society of America and University of Kansas Press, Lawrence. Also see Michael Stachowitsch; Sylvie Proídl, illustrations. 1992. The invertebrates: an illustrated glossary. Wiley-Liss, New York. Esoxidtalkcontribs 21:33, 20 June 2014 (UTC)
Neat, that's really interesting. Sounds good. Sunrise (talk) 23:52, 22 June 2014 (UTC)
I think I'll add a bit about brooding, to give it some added context. Esoxidtalkcontribs 00:57, 23 June 2014 (UTC)

Adaptations for life on land[edit]

  • Green tickY"the isopods are one of the few groups [of crustaceans] of which some members now live on land."[19] The source doesn't mention which groups of crustaceans are found on land. Another source could be used for this though.
Added a source and listed the other crustacea. Esoxidtalkcontribs 14:45, 21 June 2014 (UTC)
Looks good. Could you reword the "small number of amphipods and decapods" clause though? It could be interpreted as saying that these are a subgroup of the isopods. Putting it in a separate sentence might be one way to address this. Sunrise (talk) 23:52, 22 June 2014 (UTC)
Sure thing. Made it a separate sentence with more clarity. Esoxidtalkcontribs 01:03, 23 June 2014 (UTC)
  • Green tickY"Terrestrial isopods play an important role in many tropical and temperate terrestrial ecosystems"[20] The source doesn't support the use of "tropical and temperate," unless it's established in another source that terrestrial isopods are excluded from the polar regions.
Added a source and clarified the lack of isopods in arctic/subarctic. Esoxidtalkcontribs 15:03, 21 June 2014 (UTC)
Looks good. Sunrise (talk) 23:52, 22 June 2014 (UTC)


  • Green tickYI'm not aware of the criteria for citing text in captions (and MOS:CAPTION isn't in the GA criteria). The image description only describes the species as "an intertidal marine isopod," not carnivorous or found on sandy shores.
The article for that species, Eurydice pulchra lists a source for habitat and feeding strategy. Esoxidtalkcontribs 15:08, 21 June 2014 (UTC)
Okay, I've verified the source so I'll check this off. Sunrise (talk) 23:52, 22 June 2014 (UTC)
  • Green tickY"Most are small, dull-coloured animals" is not cited in the body. I've seen a couple of sources describing the general size range, and adding that in somewhere would be fine for me. I don't recall reading anything about coloring though.
I had a hard time finding very general descriptions like these, so I used the best I could find. Esoxidtalkcontribs 21:52, 27 June 2014 (UTC)
I think the range of color is fine - probably the best sources there are. For a general size range, might I suggest the WORMS source (currently citation 3)? Sunrise (talk) 06:33, 9 July 2014 (UTC)
Done. Cwmhiraeth (talk) 09:36, 10 July 2014 (UTC)
  • Green tickY"seven pairs of jointed limbs on the thorax" - "jointed" doesn't appear to be cited in the body.
Added general source for arthropod anatomy, including isopods. Esoxidtalkcontribs 15:36, 21 June 2014 (UTC)
  • Green tickY"Isopods are mainly scavengers or browsers but some are filter feeders, some are predators and others are ectoparasites, mostly of fish." Just noting that this is the same statement as as listed above in the "Feeding and nutrition" section. Also, this phrasing may imply that there are no endoparasitic isopods, so a different wording might be better.
Fixed lede to match body, and added another endoparasite to body. Esoxidtalkcontribs 15:36, 21 June 2014 (UTC)
  • Green tickY"The name Isopoda derives from the Greek roots ἴσος (iso-, meaning "same") and ποδός (podos, meaning "foot")."[2] This description doesn't match the one from the source ("similar" vs "same" and "podos" vs "pod"). In the second case I think the source might just be matching to "isopod," but I'm not sure which is correct. According to the Wiktionary link, "podos" is the genitive (possessive) case, and I know some species names work that way but it may or may not be true in this case.
I changed it to the nominative case, and added a dictionary source. Esoxidtalkcontribs 22:02, 27 June 2014 (UTC)

Broad in its coverage[edit]

  • Green tickY I get the feeling that isopods are found most places on Earth, but the article doesn't actually state this anywhere (unless I missed it). If they are, a wikilink to Cosmopolitan distribution may be appropriate.
  • Green tickY I’ve heard of the giant isopod before, and from a Google search I see there has been some media coverage, so a sentence or two on this might be useful. Maybe a reference to Deep-sea gigantism as well.
  • Green tickY According to this, “some isopods are routinely consumed as human food.” (I found this via the Cymothoa exigua article, where there is already a formatted citation that could be copied over.) Do you think this is important enough to include?
I have added this using a pdf source but I cannot find a suitable url for the reference (#8, Williams). Cwmhiraeth (talk) 11:12, 4 June 2014 (UTC)
Based on what I can find, I think that the PDF is the summary for a symposium presentation. I'm not sure how this situation is usually treated, but I think it's probably not a big deal. Sunrise (talk) 05:18, 5 June 2014 (UTC)
  • Green tickY You mention isopods as a pest in aquariums, but they are also a problem for commercial fisheries, e.g. see here although that article is not very descriptive. Or this article – which, if you don’t have access to it, says that Ceratothoa gaudichaudii causes disease in coho and Atlantic salmon during marine netpen farming.
  • Green tickY I think the article needs a section on evolutionary history. Currently it mentions when the first isopod fossils occurred, but the central unifying theme of biology deserves more discussion than this. :-) Some topics (contingent on sources, of course) might be: which features were present in the common ancestor (e.g. I see there is a list of synapomorphies in the Tree of Life page), which groups of isopods evolved earlier or later, etc. I would especially recommend the “Biogeographical history” section of the Tree of Life page.
I have dealt with most of these points and will work on an evolutionary history section. Cwmhiraeth (talk) 11:12, 4 June 2014 (UTC)
Let me know if I can help. Sunrise (talk) 05:18, 5 June 2014 (UTC)
Looks good. :-) Sunrise (talk) 05:25, 7 June 2014 (UTC)
  • Green tickY The ecology of isopods is probably an important topic (e.g. "[woodlice] are key regulators of plant litter decomposition"). There is also much more detail here although that’s probably not necessary for GA status. This is probably the last entry I'll add for this criterion since I've gone over most of the literature by now.
I've added a sentence about the importance of woodlice in the decomposition of plant debris. I didn't think there was enough information for a separate section on ecology, especially as the marine and freshwater isopods have a great variety of lifestyles. I'm sure they are imporrtant in their interactions with other species but it is difficult to generalise. The sources you give are mostly about how climate change might affect terrestrial isopods and I think this is beyond the scope of this article. Cwmhiraeth (talk) 06:21, 8 June 2014 (UTC)
Only the first one appears to be about climate change, but your addition is good. I wasn't asking for a full section in this case. Sunrise (talk) 01:51, 11 June 2014 (UTC)

YesY Section complete. Sunrise (talk) 01:51, 11 June 2014 (UTC)


YesY No issues found or likely to arise.


YesY No difficulties expected here.


  • I think you've chosen the images well. :-)
  • Green tickY In the infobox caption, “isopod of sandy shores” is unclear to me, but I’m having a hard time describing why. Maybe “found on sandy shores” (if that’s correct?) Although it looks aquatic to me, so “found off sandy shores” might be better.
  • Green tickY Optional: since the woodlouse picture is the first in the article outside the infobox, it might be useful to point out a couple of the key features of isopods in the caption.
Captions improved. Cwmhiraeth (talk) 11:12, 4 June 2014 (UTC)
There are some new images. Do you think they are too large? Cwmhiraeth (talk) 10:46, 10 June 2014 (UTC)
I added two, and increased the size of the parasitic isopod image. I thought it would be good to catch the eyes of readers who may not follow image links, but if they are too large feel free to resize. Esoxidtalkcontribs 20:34, 10 June 2014 (UTC)
The GA criteria don't require compliance with MOS:IMAGES, so it shouldn't be a problem either way. Sunrise (talk) 01:51, 11 June 2014 (UTC)

YesY Section complete. Sunrise (talk) 05:38, 13 July 2014 (UTC)


This section is for miscellaneous comments. I do not consider any suggestions I make here to be necessary to meet the GA criteria. You can feel free to use them, or they can serve as information for future editors of this article.

YesY This strikes me as an extremely useful source. (Freely available.) Highly detailed information on history, taxonomy, distribution, etc.

Cwmhiraeth included it. It only includes marine isopods, so keep that in mind. Esoxidtalkcontribs 20:31, 10 June 2014 (UTC)

YesY Also, since images in PLoS journals are compatible with Wikipedia, a couple of the figures look like they might be useful.

Extracted two images from that article and included them. They were quite nice. Esoxidtalkcontribs 20:31, 10 June 2014 (UTC)


  1. ^ a b c d e f Cite error: The named reference Brusca was invoked but never defined (see the help page).
  2. ^ a b c d Schotte, M.; Boyko, C. B.; Bruce, N. L.; Markham, J.; Poore, G. C. B.; Taiti, S.; Wilson, G. D. F. "World List of Marine, Freshwater and Terrestrial Isopod Crustaceans". World Register of Marine Species. Retrieved 2014-06-04. 
  3. ^ a b Cite error: The named reference AM was invoked but never defined (see the help page).
  4. ^ Wilson, G.D.F. (1989). "A systematic revision of the deep-sea subfamily Lipomerinae of the isopod crustacean family Munnopsidae 27: 1-138. [Deep-sea Isopoda]". Bulletin of the Scripps Institution of Oceanography. 27: 1–138. 
  5. ^ Alexander, David E.; Chen, Tao. "Comparison of Swimming Speed and Hydrodynamic Drag in Two Species of Idotea (Isopoda)". Journal of Crustacean Biology. 10 (3): 406–412. doi:10.2307/1548330. 
  6. ^ Williams, Ernest H. Jr. "Isopods as parasites or associates of fishes". 
  7. ^ Ronald L. Shimek (2002). "Pills, parasites, and predators; isopods in the reef aquarium". Reefkeeping. 1 (4). 
  8. ^ Cite error: The named reference WoRMS was invoked but never defined (see the help page).
  9. ^ Srour, Marc (2012-07-13). "Tongue Biters and Deep Sea Giants: The Cymothoida (Crustacea: Isopoda)". Teaching Biology. Retrieved 2014-05-08. 
  10. ^ Brusca, Richard; Coelho Vania R.; Taiti, Stefano. "Suborder Oniscidea (Terrestrial Isopods)". Tree of Life Web Project. Retrieved 2014-05-08. 
  11. ^ a b Poore, G. C.; Bruce, N. L. (2012). "Global diversity of marine isopods (except Asellota and crustacean symbionts)". PloS One. 7 (8): e43529. doi:10.1371/journal.pone.0043529. 
  12. ^ Warburg, M.R. (1987). "Isopods and Their Terrestrial Environment". Advances in Ecological Research. 17: 187–242. doi:10.1016/S0065-2504(08)60246-9. 
  13. ^ Shields, Jeffrey. "Epicaridea: The parasitic isopods of Crustacea". Virginia Institute of Marine Science. Retrieved 2014-03-23. 
  14. ^ Shields, Jeffrey. "Epicaridea: The parasitic isopods of Crustacea". Virginia Institute of Marine Science. Retrieved 2014-03-23. 
  15. ^ Shields, Jeffrey. "Epicaridea: The parasitic isopods of Crustacea". Virginia Institute of Marine Science. Retrieved 2014-03-23. 
  16. ^ Shields, Jeffrey. "Epicaridea: The parasitic isopods of Crustacea". Virginia Institute of Marine Science. Retrieved 2014-03-23. 
  17. ^ R. C. Brusca & M. R. Gilligan (1983). "Tongue replacement in a marine fish (Lutjanus guttatus) by a parasitic isopod (Crustacea: Isopoda)". Copeia. 3 (3): 813–816. doi:10.2307/1444352. JSTOR 1444352. 
  18. ^ R. C. Brusca & M. R. Gilligan (1983). "Tongue replacement in a marine fish (Lutjanus guttatus) by a parasitic isopod (Crustacea: Isopoda)". Copeia. 3 (3): 813–816. doi:10.2307/1444352. JSTOR 1444352. 
  19. ^ "Benthic animals". Icelandic Ministry of Fisheries and Agriculture. Retrieved 2014-06-04. 
  20. ^ Zimmer, M. (2002). "Nutrition in terrestrial isopods (Isopoda: Oniscidea): an evolutionary-ecological approach". Biological Reviews of the Cambridge Philosophical Society. 77 (4): 455–493. PMID 12475050. 

Cellulose digestion[edit]

The section "Feeding and nutrition" states that "cellulose is digested by enzymes secreted in the caeca." I thought that metazoa that digest cellulose need to have a symbiotic relationship with bacteria. Are isopods an exception? Can they synthesize cellulases? Aa77zz (talk) 08:11, 10 August 2014 (UTC)

It seems marine isopods are an exception. I looked this up in the source which states "Wood-boring marine isopods feed on wood by using cellulase secreted by the digestive ceca." but also states "In terrestrial woodlice, cellulose digestion is accomplished by symbiotic bacteria." The article mentions these differences. Cwmhiraeth (talk) 08:29, 10 August 2014 (UTC)
Thanks for your reply. It seems very possible. A quick search finds many articles on cellulases in animals - even in termites. Aa77zz (talk) 09:30, 10 August 2014 (UTC)

Confusing double explanations[edit]

I chanced across this article and found the introduction immensely confusing, right from the very first sentence. Isopoda is an order (group), it says. Well, is it an order or is it a group? If you think that "order" is somehow too complicated a word for the reader to understand, I think you're disastrously underestimating your audience. Offering them a choice of words that might apply makes nothing clear. Soon after, we have "segmented exoskeletons (external skeletons)". Is there any reader who will be so baffled by "exoskeleton" that they need an explanation, but at the same time have no idea how to click on links? Then finally in the first paragraph we have "some more derived taxa (advanced groups)". Indeed, "derived taxa" is a technical term that most people will not understand. However, each word is linked to somewhere the reader can find out more.

In each case, these double explanations were not helpful but confusing. They introduce ambiguity and entirely disrupt the flow of the article. So I removed them. They were first restored with the claim "Explanations are helpful to the reader. Explanations are what we are all about and an explanation of what isopods are is helpful to the reader. An explanation of the words you are using to explain something is not helpful to the reader.

The double explanations were restored with the comment "Replaced explanations which were added as part of the FAC review process". Firstly I do not see in the FAC a demand for an explanation of what an order is. Secondly it's irrelevant. Even featured articles can be improved, and something that may or may not have been said in a review two years ago is not a valid reason to reject an improvement.

I didn't edit any further but looking into the first paragraph of the main text, I see "Isopods are typically flattened dorsoventrally (broader than they are deep)". Why bother to use the word "dorsoventrally" and then explain it? Why not just say "Isopods are typically broader than they are deep"? We are not here to teach readers words just for the sake of it. Reading on, I see that the article is basically riddled with parenthetical explanations. A few examples, like the first two in the introduction, are not even complicated words and almost all of the rest can and should be written in clear, non-technical language. (talk) 11:19, 29 June 2016 (UTC)

Its all a matter of opinion. In my opinion they are helpful to readers who do not understand some of the terms used. You apparently disagree. They were there at the end of the FAC review so you may be in a minority, and in any event, the matter seems pretty unimportant to me. Though I don't know who you are, I note that you are a blocked editor so may not be in complete agreement with Wikipedia policy. Cwmhiraeth (talk) 12:33, 29 June 2016 (UTC)
If it's so unimportant to you, why did you revert twice? It really isn't a matter of opinion. If you say "order (group)", then it's obvious that it's not clear what is actually meant. Is it an order or is it a group, or is it both? It's not clear. For things like "dorsoventrally" we have clear guidelines: "Do not introduce new and specialized words simply to teach them to the reader when more common alternatives will do." I don't know what you are talking about with your strange claim about blocked - looks like a very shoddy attempt to get your own way by slandering me. Well if you want your pet article to be confusingly written, you may keep it that way. I'm not going to bother trying to persuade you of the virtues of good writing any further. (talk) 10:19, 30 June 2016 (UTC)
You reversed my edit on Isopoda using which is a blocked account. Cwmhiraeth (talk) 12:33, 30 June 2016 (UTC)