Social media is tricky when looking for fishkeeping advice, there are a lot of sources and all with their pro’s and con’s. It’s even more tricky for a beginner but I assume most reading this website are not beginners, even the most seasoned aquarist can fall into echo chambers and feel lost with knowing where to go. I hope this article can offer some help.
Some might know that I do not just have this website, I have a Youtube channel, run multiple Facebook groups and can be active on Discord. Previously I was on a few forums and sometimes will frequent the Planet Catfish forum. Social media is hectic and confusing, it can be full of drama but where isn’t that has people?
At the end of the day many fishkeepers don’t frequent a lot of social media, Youtube particularly is very focused onto those who can make videos which takes skill and time.
So what social media is there?
Throughout this article I wont include channels/groups that encourage poor welfare, out of date or inaccurate/unreliable ideas. This is not the extensive list as no doubt I’ll have missed some.
Youtube/Instagram
I would say both of these platforms are quite similar. I largely am not keen on either for learning, they are entertainment platforms. Viewer count is not about knowledge (or experience) but about entertainment value. Youtube is tricky as there is no real argument for or against, on it’s own largely it’s self focused so ideas cannot really be contested or debated. There is little ability to cite sources and it is not frequently done.
Both are so much of a bottleneck that the most knowledgeable fishkeepers inevitably will not be the most popular. The most seasoned aquarists seem to frequent other sources.
Saying all of that there are great channels, those that show different biotopes or discuss the science.
My favorite channels:
Professor Leandro Souza, (https://www.youtube.com/@LeandroSousa_IctioXingu). A great channel for anything connected to the Rio Xingu, it is largely in Portuguese but subtitles exist. Not just can you see the habitats of the various fishes but the fishes themselves.
Cam and John, The Fish Room (https://www.youtube.com/@TheFishRoom). Their weekly livestream/interview is one of the best podcasts around. They have interviewed some of the top names of fishkeeping from Ian Fuller to Project Piaba (and some Rift Valley cichlid people) and really care for advancing knowledge. If fishes aren’t entirely your thing many episodes involve interviewing brands and aquascapers.
Meenkaran, (https://www.youtube.com/@flare1979/). If you want to see anything from biotopes to husbandry and science of South East Asian fishes, no further needed to go.
Knowledgeable fishkeepers:
I put this as separate as they are kind of a different format and knowledge to be gained.
Alyssa Bentley, (https://www.youtube.com/@mangala666). One of the best Loricariid breeders, she is currently building a fishroom after many years of fishkeeping.
Dylan/DJA Aquatics, (https://www.youtube.com/@DJAAquatics). A Loricariid breeder with a lot of knowledge and passion for this group of fishes and Corydoradinae.
Graeme/Aquarium Adventures, (https://www.youtube.com/@AquariumAdventures). A great channel for fishkeeping in general, a channel that emphasizes the fact we are always learning as fishkeepers. If you want to try a different aquarium sealant other then silicone, a great channel to watch.
Paul/BigFishLad, (https://www.youtube.com/@bigfishlad4847). Good for anyone interested in keeping those larger Central/South American cichlids, what is required and a channel that shows high welfare or thoughtful care of these fishes.
StephenP, (https://www.youtube.com/@StephenP2003). Stephen has a real interest for plants and learning more about them. Not just the husbandry but also the science behind them.
Tropical Fish Hub, (https://www.youtube.com/@tropicalfishhub). A great channel largely focused on South American fishes. Looks more into their husbandry but has a lot of high welfare and thoughtful setups.
Bills Cichlid Room, (https://www.youtube.com/@BillsCichlidRoom). This channel is great for seeing a realistic fishroom with a particular focus on cichlids. Bill obviously has a lot of knowledge about a variety of freshwater fishes but particularly cichlids.
Amiidae, (https://www.youtube.com/@amiidae). This channel shows a lot of footage of rarer species from a diversity of locations.
While it has been a hot topic in the exotic pet community for a while this topic is starting to gain traction in the aquarium hobby. The Scottish Government was provided with a report by the SSPCA, Born Free Foundation and One Kind titled “Don’t Pet Me”. This report sets out a case for the restriction and banning of a number of pets although definitions are unclear they largely use the term wild animals.
When analysing a document like this it’s important to understand who wrote it, unlike scientific papers this is not peer reviewed and biases do not have to be declared. Born Free Foundation is already actively against exotic pets (https://www.bornfree.org.uk/wild-animals-pets/), this is also the case for OneKind (https://www.onekind.org/listing/category/dont-pet-me) and the Scottish SSPCA is largely an animal welfare organisation but has done a lot of really good work. The others have done misleading campaigns in the past but I wont get into them as the focus here is this one. None of the contributors seem to be stakeholders in the industry nor scientists studying the relevant taxa.
The Reports Methodology
The first thing to set out is what they mean by a wild animal. This report fails to provide a definition for a wild animal, or as they say an exotic pet, I shall be using these terms interchangeable. This lack of clarity is problematic as the definition and understanding of the term varies. The Cambridge dictionary states a wild animal as “An animal that lives in natural conditions and is not cared for by humans”, which is a broad brush but ignores any captive animals as they are obviously being cared for. UK law doesn’t seem to have a definition beyond a list of those species covered by the Dangerous Wild Animals Act 1976 which require a license. Exotic pets in an interim report with the Scottish government identified the term is misleading and inappropriate with varying definitions (https://www.gov.scot/publications/scottish-animal-welfare-commission-interim-report-exotic-pets-scotland/pages/5/). A debate in the UK parliament identified exotic pets as rare or unusual https://commonslibrary.parliament.uk/research-briefings/cdp-2015-0124/, not a helpful definition. A 2022 final report mentions rabbits and small rodents as exotic pets although doesn’t focus on these excluding dwarf hamsters (https://www.gov.scot/publications/final-report-exotic-pet-working-group-scottish-animal-welfare-commission/pages/4/). When it comes to vets it’s generally considered anything that is neither livestock, horses, a dog or cat is considered exotic. With such a broad definition this makes this 2025 report handed to the Scottish Government concerning but also open.
While literature is present on the topic of a variety of exotic pets, this report also fails to reference much of this peer reviewed scientific literature. Much of the literature provided shows a clear conformation bias rather then an argument, it only portrays one point of view. There is no discussion of the benefits and many of the citations reference trends in other countries opposed to focus on practices in the UK. Some of the sources are irrelevant e.g. the captive husbandry of slow loris (Nekaris et al., 2015) in page 31 and used it to compare to crested gecko’s, could they not find a single source that inferred that the squeaking behaviour was an example of stress in this gecko species? Just because viewers might find a behaviour cute it doesn’t mean they want to buy the animal. Ramsay et al. (2007) is used to discuss red eared sliders, a species already banned in the UK. Realistically given the very limited citations there isn’t so much I can say about them.
They claim to send a mystery shopper to a range of stores as mentioned in page 8, while it sounds ideal how do we know what stores were included and the quality of those stores? Was it just the bad eggs? Could they not say which stores they visited?
Figure 2: Some definitions provided by the Don’t Pet me report, 2025.
There are some issues with the terminology used (Fig 2), maybe it is too simplistic but they could have cited a source with a detailed definition. The one that is most odd to me is morphs, not all morphs are ‘sought after’, this phrase maybe makes it seem like there is a trend or market. A morph really is just a variant. The term morph is very specific to the reptile hobby and seems more like targeting as within other exotic pet hobbies we might use terms such as breeds or variants.
The Reports Results
Some of these results would benefit from reliable citations such as “For example, royal (ball) pythons (Python regius) are frequently wild-caught”, given the number of morphs in the UK which would not be wild caught as these are captive strains this is likely misleading. Additionally yes there will be royal pythons wild caught but are these reaching the UK? The paper that the report they mention mostly doesn’t infer this is relevant (Green et al., 2020) as the source of royals into the UK isn’t mentioned. This could be solved by asking wholesalers.
The report criticises the use of RUB’s (Really Useful Boxes), the reptile hobby already criticises this and it’s a self policing hobby that is regulating, yet there is little mention of this. This self policing trait within exotic pet communities while sometimes internally criticised is an important part of developing and improving welfare based on science and evidence within a hobby (Muka, 2022), it is not rare either. Maybe this is evidence of how the worst parts of our communities let us down, and could now be our downfall. My community here, on Youtube and Discord is not alone in providing up to date husbandry that also helps self police to the hobby. This has been somewhat recognised within the report for the hedgehog hobby (Page 12) but it makes no effort to recognise how widespread this is. There is frequent criticism of snake enclosure sizes, maybe supporting and promoting those who are encouraging evidence based husbandry would be better then making it seem like the whole hobby is doing this.
Some of the images used (e.g. Page 13) are not from the UK or represent the UK trade, many parrots in the UK will be captive bred. This is emotive imagery but not realistic.
Figure 3: Criticism of transportation by the Don’t Pet me report, 2025.
Fishes are often transported as we are well aware in bags sometimes polyboxes but these are safe for the fish in movement and there has yet to be a good alternative. The mention of bedding and ventilation for shipping fishes is just ridiculous, what bedding would they suggest? And ventilation? It’s just as bad as PETA suggesting we use tranquilisers to transport fishes. Any decor does risk breaking the bag but also if it shifts stressing out or damaging the fish.
Figure 4: Criticism of shop labelling by the Don’t Pet me report, 2025.
Some of the criticism maybe is a little odd (Figure 4), labelling a species as easy to keep or beginner friendly doesn’t mean the store isn’t recognising there is species specific requirements, it’s inferring that the husbandry is not as difficult as other species. While I disagree often with the species chosen it is not for this reason, often these species might have requirements that can be missed by someone after an ‘easy’ pet but no hobbyist usually wants their animals listed as easy.
Figure 5: Don’t Pet me report, 2025.
While a problematic scenario is provided (Figure 5) when provided with a challenging situation such as a child wanting a pet the second solution is not bad. Customers can be challenging and this second solution likely would allow the child to obtain some education from the animal, avoid an unwanted pet and hopefully get the parents involved. But without a full script much of this secret shopping experience is biased and unreliable. The report fails to recognise that sales setups are aimed to be short term and therefore often smaller then a long term setup and these are not recommended for long term care.
Issues with Data
There are frequent issues with the data provided which could be misleading but also infer to me a lack of knowledge about animal biology and husbandry.
Figure 6: Number of individual species sold from the Don’t Pet me report, 2025.
Data often needs to be properly dissected and understood or it can be misread. Figure 6 identifies cherry shrimp (Neocardinia davidi), Guppies (Poecilia reticulata, do they mean P. wingei hybrids as well?) and cichlids as the most populous species sold. There are loads of errors with this statistic. Firstly cherry shrimp and guppies are very frequent spawners and small organisms as hobbyists we know this, so it makes sense so many would be for sale. But given their size they take up much less space and instead particularly for guppies a focus would be better aimed as only buying males given females are often already pregnant. I don’t see how these two are a problem entirely being so high, they are easy going aquatics. Cichlids though is an issue, you first have the bias that this is one of the largest families of fishes with incredible diversity. So it is understandable why there would be so many. I do have an issue with data like this where there is not equitable groups provided. The fishes shown here represent likely multiple species so would represent more individuals, is that bad?
Figure 7: Top five advertised per category and number of animals in the Don’t Pet me report, 2025.
Figure 7 is very problematic to me as none of these groupings really have definitions. My criticism of the term guppy without a scientific name is the same from the previous comment. Unknown species could infer the seller doesn’t know the species, or the writers of the report have no idea, if they can’t identify the species why are they writing a report on husbandry? Is it to make the sellers look bad if it infers that the seller doesn’t know? Discus are cichlids and ‘Plecostomus’ are catfishes. The discus category is concerning as it’s pretty simple, wilds aren’t common in the UK so we are dealing with domestics which are a hybrid, it’s not even unknown they are a mixture of mostly Symphysodon tarzoo and S. aequifasciatus (Ng et al., 2021).
Plecostomus as someone who studies Loricariids is the most problematic category. Plecostomus is no longer a valid genus, Hypostomus plecostomus is barely if at all in the trade. Plecostomus as a common name is a pick and mix name, so how broad do they mean? Could they be including the Chinese algae eater, Gyrinocheilus aymonieri, which is a very frequently rehomed fish. Are they including Ancistrus as some have done? What about Loricariinae? 92 (Figure 7) would be a lot even just for Pterygoplichthys which has never been in Plecostomus. Loricariidae is popular but the term Plecostomus means very little without a definition. Many people breed Loricariids and according to the IUCN what is identified, there are still many threatened in the wild. I’m not being pedantic though, this is not a consistent term.
Exotic pet demographics
As someone who has been diagnosed with dyslexia and SpLD since I was 8 this section infuriated me. There was an obvious targeting of neurodiverse people.
Figure 8: Mentions of Neurodiversity in the Don’t Pet me report, 2025.
An unneeded targeting of neurodiversity was included (Figure 8), why this was relevant I have no idea. While they recognise precise knowledge it seems to infer there is something problematic with neurodiverse people and animals, that maybe we are less capable. Neurodiversity includes conditions from autism, dyslexia, ADHD and similar, it’s a broad term but we all think differently, this means we can problem solve. These conditions do not infer with our ability to keep animals with high welfare and in fact it might mean we can identify new solutions to husbandry problems.
They continue to target disabilities.
Figure 8b. Criticism of the disabled community in the Don’t Pet me report, 2025.
There is no need to explain how animals help with mental health, we all know that. Although I argue fishes are stress causing haha, I must say Zach, my little (6kg! but not overweight) void cat has been a blessing to me (even if he ensures he has breakfast at 2-4am no matter what). Exotics can differ a lot from traditional pets so it makes sense many provide solutions to disabled people, it could be from cleanliness and issues with fur or just fascination. This statement (Figure 8b) infers that disabled people, that includes the neurodiverse community so those with dyslexia, ADHD and autism can’t cope with their animals because we are disabled. Most of us our disability has nothing to do with animal husbandry! While I have short term memory issues, issues with understanding language it has nothing to do with how I can keep my animals. Even when I’ve broken bones I’ve still managed to do water changes, in a way my dyslexia has allowed me to problem solve around not being able to use a broken arm/wrist. It ignores how disabled people can identify new solutions due to differences in thinking. I don’t know what disabled people are frequently saying they can’t cope as that’s definitely a minority. Neurodiversity is common in fishkeeping and no one has told it’s causing them to struggle. I’ve worked in the trade and I know exactly how much I can care for and I know I can keep a lot more then I do now (academia means moving a lot).
Another concern of the report which highlights a bias is they recognise on page 21 that many keepers work with animals, qualifications vary from none to PhD. Yet in the next paragraph they state “Most people who own wild animals appear to be either irresponsible, or well-intentioned but lacking the necessary knowledge and equipment.”. This is clearly stating they think that those who work with the animals husbandry are not as knowledgeable, as who? I assume them? Do they have anything to back this up? And given Born Free has frequently campaigned against zoos it infers that they are inferring there are no husbandry experts. It infers that zookeepers and store staff, academics etc. don’t know as much as they do.
Figure 9: Don’t Pet me report, 2025.
I don’t know why Figure 9 was included, is this inferring that people who show their animals are of a low socio-economic status? And what do they mean by that? How are they judging? You can’t judge from a video or photo someone’s socio-economic status.
Figure 10: Don’t Pet me report, 2025.
No one is debating the external influences with the hobby (Figure 10), the hobby actively tries to fight it yet little mention or promotion of responsible communities.
Frequently throughout statements are made but not cited or even a lack of values provided. They state their opinions but make it unclear that they are opinions. They do not communicate with husbandry or scientific experts in a variety of groups. Frequently statements are made about the hobby that the hobby is trying to solve.
Page 29 fails to recognise the lack of availability of exotic vets or specialism of vets particularly for diverse groups. It also fails to recognise responsible communities and individuals recommend vets frequently where this is the required intervention and not a husbandry issue.
They state people blame “Flimsy enclosures were often blamed but human error was also a cause.”, both of these can easily be the cause as there are weak enclosures and an owner might not be aware. This is obviously more common with small mammals but with fishes a lid is always promoted for a variety of reasons.
On page 29 they identify the use of live feeding vertebrates, the legislation on this is tricky but it would be great if they could provide clarity as to if their sources were in the US or other countries where this is common. I have yet to hear of this in the UK.
I guess this is a positive for fishkeeping!
They do mention issues with handling on page 31, as someone whose worked with a range of exotic animals but also a fan of choice based handling. It can be useful for animals to get used to handling as sometimes care might be required, this is less common for non-mammalian exotics who lack nails or fur that needs trimming. They mention axolotls being handled which I have yet to see being common practice……. although aquatic species being handled for some such as Loricariids it allows for a quick clear assessment of the fish and as facultative air breathers it causes little harm, most people are only taking photos when being moved between setups so will be out of the water anyway. Seeing defensive as ‘cute’ is not entirely common but for some animals if handling is required confidence is needed as waiting, going in slow will likely result in an accident.
Premature death in the trade is mentioned but there are no real statistics on this and this should be recognised.
For demographics my personal concern has been the age groups between around 16-18 which will be moving for university or perhaps renting, not that they can’t keep pets but it does effect choices. Having animals younger effects where you can live given rental restrictions but also animals being banned from university halls. This has not been identified in the report yet within aquariums and reptiles there is definitely a demographic gap where there are less people between around 18-30 although I would be curious how the upper end might change.
The reports recommendations
A Positive List
The most concerning part of the report is the promotion of a positive list, this is a list of species that people would be allowed to keep. We have no idea what would be included here and the report provides little clarity other then more common exotics such as rabbits, guinea pigs and hamsters maybe wont be included? This is regardless of those three also facing similar difficulties but also have active communities promoting welfare.
This positive list could mean many things, it could mean that you could keep what you have till it passes. It might mean you cannot breed, trade or sell the animals. It could mean euthanasia. It could mean no imports. Most of these would make legal captive populations extinct.
Illegal populations will always exist but these will go underground, animals will have no access to veterinary care. While exotic vets are rare there will be even less access to them for the animals that exist legally as demand decreases, many of these animals are long lived so catfishes, parrots and reptiles would be without.
The benefits of the aquarium hobby are well known, both to people but also to the species encountered within it (Evers et al., 2019). As a hobby we do need to promote and further these benefits, we need to reduce the pressure on a small number of species but be responsible with what we keep. The hobby is a source of knowledge both from hobbyists (Marchio, 2018) who are not professionals but also from academics and husbandry experts, it has been identified previously vets will defer to hobbyists for knowledge (Walster et al., 2015).
Encounters, awareness and exposure to a diversity species will decrease. Zoos contain a very limited number of exotics for many groups such as freshwater fishes. A lot of interest in many freshwater groups which can lead to scientific research or conservation (ex-situ and in-situ) can originate from this exposure. There are many aspects of the aquarium hobby involved in ex-situ conservation and captive breeding so a positive list would remove this potentially causing an extinction of some species. Captive breeding fishes is promoted within the hobby and often not for money (Pountney, 2023).
The aquarium hobby provides an industry for locals who fish for the species we value as hobbyists. None more obvious then the cardinal tetra and discus of South America such as around Manaus. The aquarium hobby provides a job for locals, without it to support their families they would have to go into other jobs such as deforestation or mining.
The aquarium hobby, it’s exposure and the structure itself has allowed for the identification of new species, while not always classified we have systems such as the L number and CW number system. These can support and aid scientific research.
What can you do to protect your hobby?
While this is a Scottish report and aimed at restricting animals within Scotland there is no harm in making your concerns known throughout the UK. Contact your local MP with your concerns. Within Scotland be aware of who you are voting for.
OATA has great sources as the only representative for UK fishkeeping who is able to fight this report: https://ornamentalfish.org/
Amazing figure provided for OATA of the impact of the aquarium hobby in the UK from 2024-2025.
Evers, H. G., Pinnegar, J. K., & Taylor, M. I. (2019). Where are they all from?–sources and sustainability in the ornamental freshwater fish trade. Journal of Fish Biology, 94(6), 909-916.
Green, J., Coulthard, E., Megson, D., Norrey, J., Norrey, L., Rowntree, J. K., … & D’cruze, N. (2020). Blind trading: a literature review of research addressing the welfare of ball pythons in the exotic pet trade. Animals, 10(2), 193.
Marchio, E. A. (2018). The art of aquarium keeping communicates science and conservation. Frontiers in Communication, 3, 17.
Muka, S. (2022). Taking hobbyists seriously: The reef tank hobby and knowledge production in serious leisure. Studies in History and Philosophy of Science, 93, 192-202.
Nekaris, K. A. I., Musing, L., Vazquez, A. G., & Donati, G. (2015). Is tickling torture? Assessing welfare towards slow lorises (Nycticebus spp.) within Web 2.0 videos. Folia Primatologica, 86(6), 534-551.
Ng, T. T., Sung, Y. Y., Danish-Daniel, M., Sorgeloos, P., de Peer, Y. V., Wong, L. L., & Tan, M. P. (2021). Genetic variation of domesticated discus (Symphysodon spp.). Aquaculture, Aquarium, Conservation & Legislation, 14(2), 832-840.
Pountney, S. M. (2023). Survey indicates large proportion of fishkeeping hobbyists engaged in producing ornamental fish. Aquaculture Reports, 29, 101503.
Walster, C., Rasidi, E., Saint-Erne, N., & Loh, R. (2015). The welfare of ornamental fish in the home aquarium. Companion Animal, 20(5), 302-306.
Hypancistrus have long been an issue for hobbyists and taxonomists providing challenges to identify and define what is a species, over time a few have been described but leaving one of the most common species.
This topic is tricky for scientists regarding how a species is defined and where do you draw a line, even trickier for hobbyists. The Rio Xingu species have been particularly tricky as there are many striped species with only Hypancistrus zebra being particularly distinctive. For the hobbyist the L number system can add to the confusion as while different individuals can be given different L number it doesn’t infer they are different species. Morphology can be tricky to navigate as there are many very diverse species both morphologically and genetically for example Baryancistrus xanthellus (of which does include a green variant, verde that is not B. chrysolomus) or Peckoltia sabaji (Fig 1; Magalhães et al., 2021; Armbruster 2003).
Figure 1: The morphological diversity of Baryancistrus xanthellus, the gold nugget pleco (L177, L018, L081, L085, verde) as featured in Magalhães, K. X., da Silva, R. D. F., Sawakuchi, A. O., Gonçalves, A. P., Gomes, G. F. E., Muriel-Cunha, J., … & de Sousa, L. M. (2021). Phylogeography of Baryancistrus xanthellus (Siluriformes: Loricariidae), a rheophilic catfish endemic to the Xingu River basin in eastern Amazonia. Plos one, 16(8), e0256677.
Some of this morphological and genetic diversity can be based on different populations and localities, it is tricky to infer whether there is interbreeding as to when and extent this occurs without detailed analysis for both morphologically and genetically. We also risk drawing lines between populations or individuals of the same species that don’t exist in nature.
Commonly understood is the importance of species as a biological unit and in some manner it is, but this is no one overarching definition for a species, it’s much more complex then that. As said earlier species can be both morphologically and genetically diverse or not at all, it varies so much and on where the line is drawn. The common misconception is that genetics solves any issues with defining a species but when you create these trees to plot species different genes, regions or even whether you use mitochondrial or nuclear DNA can infer different groupings. But this reliance on species being the important factor that matters for many aquarists ignores much of this and can lead to splitting species into unrealistic groupings. Realistically like the killifish and Poecilidae sides of the hobby, we need to recognize populations are as valuable as species, even if they cross or not. Populations might have unique genetics or morphology, doesn’t make them different species but we should really think through how we breed our fishes and what individuals we choose. If fishes come from different suppliers maybe double checking locality, maybe considering if certain captive bred fishes are useful for maintaining a population.
So in summary just because some species might look different it doesn’t mean they are but doesn’t mean they aren’t distinct populations that shouldn’t be valued.
Description for Hypancistrus seideli and H. yudja:
Sousa LM, Sousa EB, Oliveira RR, Sabaj MH, Zuanon J, Rapp Py-Daniel L. (2025). Two new species of Hypancistrus (Siluriformes: Loricariidae) from the rio Xingu, Amazon, Brazil. Neotropical Ichthyology. 23(1). https://doi.org/10.1590/1982-0224-2024-0080
These exciting descriptions help us understand the Loricariids we keep in the aquariums better and more accurately describe them. Hopefully it leads to further studies of Hypancistrus.
Figure 2: Hypancistrus seideli as featured in: Sousa LM, Sousa EB, Oliveira RR, Sabaj MH, Zuanon J, Rapp Py-Daniel L. (2025). Two new species of Hypancistrus (Siluriformes: Loricariidae) from the rio Xingu, Amazon, Brazil. Neotropical Ichthyology. 23(1). https://doi.org/10.1590/1982-0224-2024-0080
This species includes the L numbers: L333, L066, L236, L287, L399, L400.
This species includes the common names: King tiger pleco, maze zebra pleco.
Diagnosed by alternating dark and pale vermiculation’s from currently described species although recognised as extremely varied (Sousa et al., 2025). Hypancistrus seideli covers a wide range of the Hypancistrus diversity in the Rio Xingu and some of the most popular species in the aquarium trade. Although morphologically diverse (Fig 2) there it seems to not have the same amount of molecular diversity so further inferring at least L066 and L333 regardless are the same species. Phylogenetically there also seems to be an issue to designate them as different species given L066 and Belo Monte seem to be paraphyletic (Cardoso et al., 2016). Although using sequences from a public database does rely on correct identification of those sequencing the samples (Fig 3).
Figure 3: Molecular phylogeny using the COI barcode sequences located from a public database as featured in: Cardoso, A. L., Carvalho, H. L. S., Benathar, T. C. M., Serrao, S. M. G., Nagamachi, C. Y., Pieczarka, J. C., … & Noronha, R. C. R. (2016). Integrated cytogenetic and mitochondrial DNA analyses indicate that two different phenotypes of Hypancistrus (L066 and L333) belong to the same species. Zebrafish, 13(3), 209-216.
Etymology: Hypancistrus seideli is named after the well known and respected aquarist Ingo Seidel who has contributed a lot to the knowledge of Hypancistrus (Sousa et al., 2025).
Habitat: While the paper doesn’t go into detail that isn’t well known it describes their environment as rocky with strong currents (Sousa et al., 2025).
Figure 4: Hypancistrus yudja as described in: Sousa LM, Sousa EB, Oliveira RR, Sabaj MH, Zuanon J, Rapp Py-Daniel L. (2025). Two new species of Hypancistrus (Siluriformes: Loricariidae) from the rio Xingu, Amazon, Brazil. Neotropical Ichthyology. 23(1). https://doi.org/10.1590/1982-0224-2024-0080
This species includes the L numbers: L174.
This species includes the common names: Ozelot pleco.
Diagnosed by large brown splotches and saddles on a tanned background (Sousa et al., 2025).
Etymology: Named after the Yudjá people of the Volta Grande, Rio Xingu, Brazil who are located in the same area as these fishes and described as equally threatened by the Belo Monte dam (Sousa et al., 2025).
Habitat: Located specifically from deep but rocky waters but remains hidden in crevices for large amounts of time (Sousa et al., 2025).
Armbruster, J. W. (2003). Peckoltia sabaji, a new species from the Guyana Shield (Siluriformes: Loricariidae). Zootaxa, 344(1), 1-12.
Cardoso, A. L., Carvalho, H. L. S., Benathar, T. C. M., Serrao, S. M. G., Nagamachi, C. Y., Pieczarka, J. C., … & Noronha, R. C. R. (2016). Integrated cytogenetic and mitochondrial DNA analyses indicate that two different phenotypes of Hypancistrus (L066 and L333) belong to the same species. Zebrafish, 13(3), 209-216.
Magalhães, K. X., da Silva, R. D. F., Sawakuchi, A. O., Gonçalves, A. P., Gomes, G. F. E., Muriel-Cunha, J., … & de Sousa, L. M. (2021). Phylogeography of Baryancistrus xanthellus (Siluriformes: Loricariidae), a rheophilic catfish endemic to the Xingu River basin in eastern Amazonia. Plos one, 16(8), e0256677.
Identifying Corydoradinae Catfish by Ian Fuller and Hans Evers has been long awaited by many catfish enthusiasts whether Corydoradinae is their interest or other Siluriformes. Using the vital recent revision of the genus (Dias et al., 2024) we now have an accompanying book accessible to hobbyists but also enthusiasts.
The revision of Corydoradinae was long needed as in some way resurrecting previous genera and reflecting the previous lineage system hobbyists used, this lineage system was also reflected in the fishes phylogeny/evolution (Dias et al., 2024). Revising the genus Corydoras and subfamily Corydoradinae reflects the morphology/anatomy and ecology better and helps us understand how to keep our Corydoradinae better.
This book offers a modern view at the group brimming with lifetimes of experience and knowledge. I need not introduce the authors as both are extremely well respected not just within Corydoradinae, catfishes but the hobby in general. This collaboration creates the perfect all round collaboration.
The science is always useful to really understand aquariums and how we keep our fishes of which some sources very much lack. Identifying Corydoradinae includes some fascinating science you wont see included elsewhere that is described in an easily understood manner to someone who might not be trained in the sciences. One of the most interesting topics was genome expansion written by Professor Martin Taylor, a scientist who studies the genetic aspects of Corydoradinae. I also very much enjoyed the section on toxins or poisons within Corydoradinae from Professor Eric Thomas as this is at the cutting edge of science, it’s a topic that is not well understood yet this book offers the latest knowledge as to the topic. For me as having an interest in ecology I was really keen to see mentions as to the fishes ecology and habitats. The ecology section was very useful for hobbyists in describing actually where these fishes are found from experience and knowledge, giving the hobbyist an idea of how to keep the fishes and breed them. Diet has sometimes been misunderstood in the hobby and the inclusion of what we know these fishes feed on is no doubt a benefit. Dr. Luiz Tencatt goes into detail on these fishes diets and hopefully this helps hobbyists know what to feed their fishes.
The layout of the book is useful for the hobbyist as logically passes through the genera before the described species and then the undescribed. This means the hobbyist can quickly identify the species they are most interested in at the time. Brochis is additionally split up which helps identify the various lineages, not completely removing the lineage system therefore the usefulness of it but that would require another scientific revision.
All the species are clearly explained with distributions, size and also detail as to their identification and ecology. To help the enthusiast who might not be too clear on the various genera there is a guide to the various genera and the key features a hobbyist can use to identify them. Plenty of clear images are provided of not just the adults but variants and as the fish ages.
In conclusion, this is a great book with so much detail for any catfish enthusiast. It provides information to help the hobbyists understand a large group of catfishes that can be tricky to identify. Certainly a book you can read in one session but for many years will be of great use.
References:
Dias, A.C., Tencatt, L.F., Roxo, F.F., Silva, G.D.S.D.C., Santos, S.A., Britto, M.R., Taylor, M.I. and Oliveira, C., 2024. Phylogenomic analyses in the complex Neotropical subfamily Corydoradinae (Siluriformes: Callichthyidae) with a new classification based on morphological and molecular data. Zoological Journal of the Linnean Society, p.zlae053.
Previously Tetradontiformes in South America were previously recognised as Sphoeroides and Colomesus but with the latest scientific evidence Colomesus has been synonymised with Sphoeroides. Sphoeroides (syn. Colomesus) contains two freshwater species, S. ascellus and S. tocatinensis, particularly the former is a frequent import for the aquarium trade.
Figure 1: The species of the revised Sphoeroides as described in Araujo et al. (2023).
This study used molecular phylogenetics to identify a phylogeny of the genus Sphoeroides (Fig 2) discovering the paraphyletic nature of Colomesus. The gene COI from the mitochondrial genome was used, which does beg the question how the phylogeny would differ with more genes including contributions from the nucleus.
Figure 2: Phylogeny of the South American Tetraodontiformes according to Araujo et al. (2023).
While this has changed a lot it’s possible more revisions and adjustments will be made, science has some level of opinion so it’s going to be an interesting future.
Source:
Araujo, G. S., Kurtz, Y. R., Sazima, I., Carvalho, P. H., Floeter, S. R., Vilasboa, A., … & Carvalho-Filho, A. (2023). Evolutionary history, biogeography, and a new species of Sphoeroides (Tetraodontiformes: Tetraodontidae): how the major biogeographic barriers of the Atlantic Ocean shaped the evolution of a pufferfish genus. Zoological Journal of the Linnean Society, zlad055.
The Scientific Fishkeeper 