# Talk:Balanus trigonus

This review is transcluded from Talk:Balanus trigonus/GA1. The edit link for this section can be used to add comments to the review.
Nominator: Cremastra (talk · contribs) 17:39, 19 January 2025 (UTC)
Reviewer: Esculenta (talk · contribs) 18:54, 19 January 2025 (UTC)

Hi, I'll review this. Comments coming in a day or two. Esculenta (talk) 18:54, 19 January 2025 (UTC)
Comments – first pass through, mostly thinking about WP:WIAGA criterion 3a (broadness). Esculenta (talk) 17:45, 20 January 2025 (UTC)

General thoughts about criterion 3a: I think the article could benefit from a clear description of life cycle stages, with info about sexual maturity timing, breeding frequency, and fecundity, larvae development and settlement. There's limited discussion of interactions with other species, no mention of predators, and limited information about its role in marine communities.
the common name triangle barnacle is introduced in the lead but this name isn't sourced later in the article
 Done
the taxonomy section is somewhat lacking. Darwin said quite a bit about the species in the protologue; why not briefly summarise that (e.g. what he thought it main characteristics were, what he thought the distribution to be; what he thought it was closely related to, what species he found it associated with); a page # for the Darwin source would be useful too
 Done
orientation isn't mentioned in the article, but apparently it's an important factor in optimizing food intake for this filter-feeding organism doi:10.1007/BF00389195
 Added
this source provides much more detailed historical context about when B. trigonus first appeared in different regions, which could enhance the Distribution section:
First Atlantic basin record: 1860s in Brazil
Mediterranean Sea: First recorded in 1920s
U.S. Atlantic and Gulf coasts: First appeared in 1950s
It also discusses how B. trigonus may have competed with and potentially displaced B. calidus along the Atlantic coast in the 1980s. It also includes information about the species' tolerance to different environmental conditions that isn't in the Wikipedia article, such as its preference for higher salinity environments. While the Wikipedia article mentions Tertiary fossils briefly, the paper provides much more detailed information about verified fossil locations in the Pacific basin and discusses the absence of verified Atlantic basin fossils.
 Done
doi:10.3989/scimar.1998.62n1-259 this paper mentions several bits of info that might enhance the article: growth and size information, and the significant geographical variation in growth rates; mortality patterns (about 50% of recruits die within 3-4 weeks of settlement; survival probability increases after week 7 from settlement; mortality rates vary by geographical location, e.g., higher in New Zealand where 50% die within 1-2 weeks); orientation behaviours; recruitment patterns; environmental response
 Done
this paper discusses how Balanus trigonus is able to uptake such extremely high levels of toxic metals (an ability not mentioned in the Wikipedia article)
mentioned
There's a paper about barnacles encrusting the lobster Panulirus gracilis in Mexico here. BTW, this source calls it the "acorn barnacle) (not mentioned in the Wikipedia article), and has several crisp CC-by-SA 4.0 pics that might enhance the article if so desired.
 Added (Acorn barnacle is a generic term)
this article has more details about its larval development timeline (e.g. Takes 9-13 days (average 11 days) from newly hatched nauplius to cyprid stage; goes through six distinct nauplius stages before the cyprid stage; the nauplius larvae are positively phototactic); specific growth measurements, larval morphology
 Added
I think the discussion of the mitochondrial genome sequencing focuses on a relatively minor technical detail (the base pair count difference) while missing the broader scientific significance of why these sequences were obtained and what they revealed. The cited studies suggest that the sequencing was done to better understand the evolutionary relationships within Cirripedia, to help clarify the phylogenetic position of B. trigonus within the Balanidae, and to provide molecular markers for studying population genetics and biogeography. A more meaningful addition to the Wikipedia article would discuss how the mitochondrial genome data helped resolve taxonomic relationships and supported other phylogenetic findings about barnacle evolution. The article could explain how molecular data complemented traditional morphological classification methods.
 Done – they also disagree on taxonomic relationships.
did you know they've experimented with using an extract of the barnacle to try to reduce fouling in mussel farms? doi:10.1016/j.aquaculture.2017.10.012
"Triangle barnacles are medium-sized" I don't have any idea what "medium-sized" means here; actual measurement ranges would be far preferable.
 Done
"growing to tall." missing something here
 Done
Can GBIF be used as a reliable source for distribution? From my take on several sources, understanding this species' distribution requires: careful examination of historical records; verification of specimens; understanding of potential misidentifications; knowledge of historical shipping patterns; and understanding of introduction events. GBIF data has known limitations: records may represent misidentifications; historical records may be unreliable; occurrence data may be biased by sampling effort; introduction events may confuse native vs. non-native ranges; data quality and verification varies significantly between sources. This species presents particular challenges because it can easily be confused with other Balanus species; its range has expanded significantly through human activities; historical records require careful interpretation and some reported occurrences may be from ship hulls rather than established populations. I think it might be a better idea to use peer-reviewed literature as primary sources for distribution data, and use GBIF as a supplementary source while acknowledging its limitations.
You're right. I'll work to rewrite the Distribution section.
 Done
"Barnacle's cirri, the legs that they use to feed themselves" I don't think it's correct to refer to these as "legs" (it would be an unusual term for sessile animals); how about "feeding appendages"?
 Done
I noticed that the article had an unproductive peer review (unfortunate); much of what I wrote above I would have suggested in the PR. Now I'm not suggesting that all of these sources need to be used to promote the article to GA ("broadness" is subjective), but perhaps it might help you expand and enhance the article somewhat.
I closed the peer review very early because I basically changed my mind about it: based on my past experiences with the PR process, feedback would take a very long time to come and then be minimal and not worth the wait, so I decided to nominate this for GA without a prior peer review. Cremastra (talk) 21:55, 20 January 2025 (UTC)
User:Esculenta What do you think of the article's scope now? I'll polish up the phrasing's rough edges later, but content and broadness-wise, is it an improvement? Thanks, Cremastra (talk) 00:41, 23 January 2025 (UTC)
Looking much "broader" now! I'll be back for a deeper dive soon.  Esculenta (talk) 03:15, 23 January 2025 (UTC)
Comments, 2nd pass – focussing on prose and images. Have made several (hopefully helpful) suggestions for improving the flow of the prose. None of these are mandatory! Esculenta (talk) 17:10, 24 January 2025 (UTC)
Lead

consider switch from plural ("they") to singular ("it") only when it makes sense. Alternatively, keep it consistently plural throughout.
Maybe tighten the wording in the first couple of sentences (which repeats "barnacle" 3 times), e.g., "Balanus trigonus, the triangle barnacle, is a steep-sided, conical barnacle in the family Balanidae. It has six shell plates and is dark pink in colour."
"Originally found only in the Indo-Pacific and the east Pacific coast, they were introduced to the Atlantic Ocean in the 19th century, probably through anthropogenic means, and are now found worldwide." suggest "Originally found only in the Indo-Pacific and along the eastern Pacific coast, it was likely introduced to the Atlantic Ocean in the 19th century through human activity and now has a global distribution." tightens the prose a bit and removes jargony "anthropogenic"
"Usually living on subtidal rocks and shells, they are also by nature foulers of ships and dock infrastructure"
clarify mention of mito genome: "The species was first described by Charles Darwin in 1854. Its mitochondrial genome has since been sequenced twice, though the results conflict slightly, leaving its phylogenetic position unresolved."
Taxonomy

suggest streamlining references to Darwin's observations; instead of repeating "Darwin found … Darwin observed … Darwin thought", condense into fewer sentences, e.g. "Charles Darwin first described the species in 1854, noting its wide distribution and that juveniles closely resemble Balanus tintannabulum. He recorded it alongside B. tintannabulum, B. psittacus, B. improvisus, B. amphitrite, and Elminius modestus, and regarded it as most closely related to Balanus spongicola."
Genetics

I think the presentation of the info in the section could be tweaked for better flow; I also don't think that some of the technical details are appropriate for this article (e.g. # of samples tested, position of branch points, bootstrap value). Here's a suggested revision: "A 2021 study from South Korea determined that the triangle barnacle’s mitochondrial genome comprises 15,336 base pairs and 37 genes—22 tRNA genes, two rRNA genes, and 13 protein-coding genes. In comparison, humans have roughly 20,000 protein-coding genes in total. However, another study from China, also published in 2021, found a slightly larger mitochondrial genome size (15,560 base pairs) in Chinese specimens, even though the gene counts were the same. Both teams aimed to resolve the species' phylogenetic position, yet their analyses placed B. trigonus in different clades."
suggest linking the taxa shown in the cladograms
Description

suggest removing extra phrasing, combining short sentences about shell plates, and using parallel sentence structure, e.g. "Triangle barnacles typically measure about 2 cm in diameter and form a steep-sided, conical shape. Their six-part shell wall is composed of dark pink plates that bear white, rib-like ridges and pores. Each plate consists of a triangular central area (the parietes) and overlapping side segments (the radii), which are paler in colour. A flat, calcareous basis attaches the barnacle to its substrate, while the top opening (the orifice) is triangular and can be sealed by two opercular plates, the scutum and the tergum. In living specimens, the scutum is usually visible and features rows of furrows, whereas the tergum has a broad spur that can occupy up to half the opercular valve's width."
Distribution

suggest consolidating repeated statements that is "introduced" and "not native" to the Atlantic so you do not restate the same concept multiple times in a short space; and to keep the timeline of spread in logical sequence (e.g., earliest Atlantic record → subsequent spread → modern distribution), e.g. "Originally native to the Indian and Pacific oceans, B. trigonus now has a cosmopolitan distribution. Although once presumed native to parts of the Atlantic, later evidence confirmed that all Atlantic populations are introduced, likely via ship hulls and other anthropogenic means. The first Atlantic record dates to 1867 in southern Brazil, followed by reports in Madeira, the Azores, and along the African coast. By 1877, it was reported on ships arriving at Cape Cod, although the record remains questionable. Today, it is common along much of the western Atlantic and abundant in the Mediterranean."
Adult development

"A lab study showed that 50% of the barnacles died by the third and fourth weeks after attachment." suggest "In laboratory conditions, half of all barnacles died within 3–4 weeks of attachment."
"The same study showed that barnacle orientation can change with age. The primary factor affecting orientation is water movement, but light also affects it." suggest "As they age, barnacles adjust their orientation primarily in response to water movement and secondarily to light."
"Generally, the barnacles orient themselves perpendicularly to the water movement's axis… " suggest "They typically position themselves perpendicular to water flow. Caribbean and Florida populations reach maximum size in about 20 weeks, though New Zealand specimens grew both larger and faster, gaining 1.8 millimeters in under four weeks. This stark difference, potentially due to geographic variation or methodological differences in measurement, led researchers to call for comparative studies to resolve the discrepancy."
Notes

"Which he spelled "Sidney"." is it really encyclopaedic info to call out a typo made by Darwin?
I saw it as a historical spelling rather than a typo, but I still removed it.
Thanks for including & citing the common name; I assume it's derived from the species epithet trigonus, but there isn't any explanation of what was the rationale for applying this epithet to the species. Judging from the images, it seems like this might be referring to the shape of the plate parietes, but perhaps you might be able to include a source that says so explicitly?
I was actually under the impression that trigonus referred to the shape of the orifice, although I may have made that up. (All parietes are triangular, by the way). Cremastra (talk) 18:49, 24 January 2025 (UTC)
Images

All three images have licenses appropriate for use in Wikipedia. Perhaps the captions could be beefed so that they better highlight the key diagnostic features mentioned in the Description section? e.g., instead of "Side view of adult triangle barnacles in Spain" (don't think the location is important here), how about "Side view of several triangle barnacles showing their characteristic ribbed pink shell plates and white radii (the paler overlapping segments between plates)." Instead of "Top view of a triangle barnacle near Auckland, part of its native range in the Indo-Pacific.", how about something like "Close-up view of a triangle barnacle's orifice, showing the dark triangular opening characteristic of the species. The pink colouration of the shell plates and white ridges are also visible." For the lead image, how about "Cluster of triangle barnacles with characteristic pink-striped shells and triangular openings, found on a shell collected from Portugal, where this species is non-native to the Atlantic."

To editor Esculenta: I've implemented most of these changes, but I do disagree with some of them. Specifically:

Genetics section: this is my main disagreement: I think it's important to give these details about the differences in their phylogenetic results, because it illustrates the differences – (fairly high levels of certainty as seen in the bootstrap values, but one more confident than the other), different sample sizes, and how different the results were – instead of summarizing down into an overly-concise sentence or two. Without that part of the section, readers would have to rely on the cladograms I made, which shouldn't be a substitute for prose. I'm willing to slim it down a little (maybe the number of species considered isn't necessary) and/or give more definitions and glosses if you think it's overly technical, but I'm reluctant to remove all that you suggested removing.
Be careful here: bootstrap values are study-specific statistical measures that depend on each analysis's unique dataset, methods, and parameters. They cannot be meaningfully compared across different studies to claim one has "higher confidence" than another. Each bootstrap value is only valid within the context of its own analysis. In the article, the direct comparison of bootstrap values (84 vs 100) implies a cross-study comparison of confidence that is statistically inappropriate. This wording needs revision. Additionally, the explanation of bootstrap values ("Bootstrap values are one way to measure the probability that a given pairing is correct – higher numbers mean more confidence") is oversimplified and could reinforce misunderstandings about comparing across studies. I suggest removing direct comparisons between the studies' bootstrap values and report each study's findings separately without implying one is more reliable; and focus more on what the phylogenetic analyses revealed about relationships within Cirripedia. Esculenta (talk) 21:33, 25 January 2025 (UTC)
Description I haven't 100% made these changes, but I did most of them. There is such a thing as too much concision. Specifically, I retained the explanation of the causes of the indentations (the crossing furrows and ridges), as well as the height measurement, which I don't see the need to remove.
Thank you for a thorough review. Cremastra (talk) 20:46, 25 January 2025 (UTC)
You're welcome! Not quite done yet ... Esculenta (talk) 00:09, 26 January 2025 (UTC)
Spot checks

all spot checks were ok, but for this one:
"but not beyond 60 metres (200 ft) below the surface.[10]: 362 [3]" Neither of the cited sources specifically supports this detail; the New Zealand source has a line down the side of the page suggests that the deepest depth recorded in the NZ locales it discusses is a little less than 58 metres, but it is unclear if this depth measurement can be extrapolated to its entire range.
Regarding depth, I note that Werner 1967 (p.72) says this: "Balanus trigonus has been reported in many places from the sublittoral zone, not infrequently to 450 m, and at least once from 3000 m". Esculenta (talk) 00:40, 26 January 2025 (UTC)
To editor Esculenta: fixed. Cremastra (talk) 15:46, 26 January 2025 (UTC)
Ok, I think the article now meets the GA criteria. Promoting now. Cheers, Esculenta (talk) 16:13, 26 January 2025 (UTC)

Thank you! Cremastra (talk) 16:14, 26 January 2025 (UTC)