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21/04/2026

15/04/2026

Scientists have discovered a new species of miniature marsupial frog in the Peruvian Amazon that carries its young in a natural pouch on its back, a research institute reported Wednesday.

09/04/2026

The evolution of lures in anglerfishes: Investigating nature's tackle box. Researchers explore the bizarre tackle boxes of anglerfishes, publishing new details on the evolutionary history of their lures. More than 100 species were studied to see how the lures evolved in different ways (mechanical, chemical and bioluminescent) to attract prey and maybe even mates in the deep sea.

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
The Evolution of Lures in Anglerfishes (Acanthuriformes: Lophioidei): Investigating Nature's Tackle Box

Open-access - https://bioone.org/journals/ichthyology-and-herpetology/volume-114/issue-1/i2025018/The-Evolution-of-Lures-in-Anglerfishes-Acanthuriformes--Lophioidei/10.1643/i2025018.full
Sci-comm post - https://news.ku.edu/news/article/research-traces-evolution-of-anglerfishes-famed-fishing-rod-lures

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Alex J. Maile, Matthew P. Davis "The Evolution of Lures in Anglerfishes (Acanthuriformes: Lophioidei): Investigating Nature's Tackle Box," Ichthyology & Herpetology, 114(1), 103-118, (27 March 2026)

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
Anglerfishes (Lophioidei) exhibit extraordinary morphological and behavioral adaptations for luring prey, yet the evolutionary history and diversification implications of their lure types remain poorly understood.

Here, we use a published total-evidence phylogeny of anglerfishes and their allies that integrates ultraconserved elements (UCEs), mitochondrial data, and morphological characters to investigate the origins and evolution of luring strategies across the clade.

Our results indicate that mechanical lures evolved early, originating in the common ancestor of the Lophioidei during the Late Cretaceous. Chemical luring evolved independently twice: once in batfishes (Ogcocephalidae) during the Eocene, and again in the frogfish 𝐴𝑛𝑡𝑒𝑛𝑛𝑎𝑟𝑖𝑢𝑠 𝑠𝑡𝑟𝑖𝑎𝑡𝑢𝑠. Bioluminescent lures arose once within a derived deep-sea ceratioid lineage during the Oligocene. Bioluminescent luring is associated with major ecological transitions into pelagic deep-sea environments, elevated diversification rates, and key anatomical innovations, including the evolution of an escal pore and elaborate escae, which are potentially involved in both prey attraction and s*xual signaling. Morphological variation in the illicium, the esca, and associated structures is most pronounced in ceratioid taxa, reflecting a complex interplay of ecological and behavioral factors shaping lure morphology across habitats.

We also identify consistent patterns linking rotational range with documented luring behaviors, alongside a trend toward increased lure length that positions the esca in front of the mouth, bringing prey within striking distance during predation. Together, these findings offer new insights into the evolutionary origins and functional diversity of anglerfish lures and underscore the influence of morphology and environment on their remarkable predatory strategies.

𝗣𝗵𝗼𝘁𝗼 𝗖𝗿𝗲𝗱𝗶𝘁
Top - Variation of length among luring apparatus components among anglerfishes and their allies. Lure components include esca (E), illicium (I), and exposed pterygiophore (P). Scale bars represent 2 mm. Lophioideo: (A) Lophiodes caulinaris, LACM 8836-10. (B) Lophiodes miacanthus, LACM 46040-3. (C) Lophiomus setigerus, LACM 44743-7. (D) Lophius americanus, LACM 34328-1. Antennarioideo: (E) Antennarius avalonis, LACM 49991-1. (F) Histrio, LACM 8975-1. (G) Kuiterichthys sp., LACM 11537-1. (H) Lophiocharon trisignatus, LACM 54171-1. Ogcocephaloideo: (I) Dibranchus erinaceus, LACM 33699-2. (J) Halieutaea fitzsimonsi, LACM 44745-6. (K) Malthopsis mitrigera, LACM 56294-1. (L) Ogcocephalus darwini, LACM 43975-2. (M) Zalieutes elater, LACM 6552-2. Chaunacoideo: ( N ) Chaunax sp., LACM 44750-3. (O) Chaunax sp., LACM 35843-1. Ceratioideo: (P) Caulophryne polynema, LACM 33923-1. (Q) Centrophryne spinulosa, LACM 31105-24. (R) Ceratias tentaculatus, LACM 11025-7. (S) Cryptopsaras couesii, LACM 11231-1. (T) Bufoceratias wedli, LACM 34272-1. (U) Gigantactis vanhoeffeni, LACM 45001-1. (V) Himantolophus sagamius, LACM 43760-1. (W) Himantolophus albinares, LACM 57239-2. (X) Borophryne apogon, LACM 30053-10. ( Y ) Linophryne densiramus, LACM 38440-1. (Z) Melanocetus murrayi, LACM 36113-1.

Middle left - The Anglerfish species 𝐵𝑢𝑓𝑜𝑐𝑒𝑟𝑎𝑡𝑖𝑎𝑠 𝑤𝑒𝑑𝑙𝑖 from the Field Museum of Natural History. Photo by Matthew Davis.

Middle right - Fossil-calibrated, genus-level phylogeny of anglerfishes, based on the total-evidence maximum-likelihood tree from Maile et al. (2025), with character-state reconstruction of luring types, luring-angle ranges, and lure morphometrics normalized to standard length (SL). Fossil calibration numbers correspond to entries in S1 Text (see Supplemental Text 1 for fossil justifications and placement; see Data Accessibility). Confidence intervals for node ages were estimated from 100 nonparametric bootstrap replicates; blue bars at nodes indicate 95% confidence intervals on divergence times. Lure types are shown by ancestral-state mapping; luring angles are grouped into six categories (shades of green) defined as (1) 0–37.5°, (2) 37.5–75°, (3) 75–112.5°, (4) 112.5–150°, (5) 150–187.5°, and (6) 187.5–230°. Lure-to-SL ratios are displayed as paired bars: the first bar indicates combined illicium and exposed pterygiophore length (IL), and the second bar represents esca length (EL); together these comprise total lure length (TLL). See Supplemental Figure 1 for the full fossil-calibrated phylogeny (see Data Accessibility).

Bottom - Lure component morphometric and rotational range parameters. (A) Lure morphometric delimitations include exposed pterygiophore + illicium length (IL), esca length (EL), and total exposed lure length (TLL). (B–G) Lure rotational range extension parameters include: (B) Antennarioideo and Lophioideo; (C) Chaunacoideo; (D) non-specified ceratioids; (E) Caulophrynidae (Ceratioideo); (F) Bufoceratias (Diceratiidae; Ceratioideo); (G) Gigantactinidae (Ceratioideo). Gray/white circles indicate vertex of lure angle. White arrows indicate the forward-stop positions (FS) and backward/resting-stop (RS) position in lure rotation (LR). Specimens from A–G are presented in lateral view, anterior to left, and include: (A) Linophryne densiramus, 60 mm SL, LACM 38440-1; (B) Histrio histrio, 138 mm SL, LACM 8975-1; (C) Chaunax sp., 158 mm SL, LACM 44750-3; (D) Himantolophus sagamius, 348 mm SL, LACM 60082-1; (E) Caulophryne polynema, 131 mm SL, LACM 33923-1; (F) Bufoceratias wedli, 64 mm SL, LACM 34272; (G) Gigantactis vanhoeffeni, 226 mm SL, LACM 45001-1.

Copyright © 2026 by the American Society of Ichthyologists and Herpetologists. Published in the Ichthyology & Herpetology journal. This paper is released under a Creative Commons Attribution 4.0 International (CC-BY-4.0) licence.

19/03/2026

Watching the watchers: emperor cichlids (𝐵𝑜𝑢𝑙𝑒𝑛𝑔𝑒𝑟𝑜𝑐ℎ𝑟𝑜𝑚𝑖𝑠 𝑚𝑖𝑐𝑟𝑜𝑙𝑒𝑝𝑖𝑠), one of the largest cichlid species, can perceive attention towards their offspring by divers.

Sensitivity to gaze, or the ability to notice where others are looking, has been widely studied in species such as primates and birds, but has received far less attention in fish. To address this gap, researchers from Japan travelled to Lake Tanganyika in East Africa to investigate how fish respond to being watched.

The team conducted a series of underwater experiments with breeding pairs of cichlids to see if they could distinguish between a diver looking at them versus a diver looking at their offspring. They chose this particular species because it is one of the largest species in its family and can be aggressive when guarding its young.

“These findings suggest that fish may possess a rudimentary form of ‘attention attribution’—the ability to recognize where another individual’s focus lies. Consequently, we may need to account for the role of ‘gaze’ in shaping wildlife responses within ecotourism and conservation contexts.”

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
Watching the watchers: emperor cichlids can perceive attention towards their offspring by divers

Open-access - https://royalsocietypublishing.org/rsos/article/13/3/251919/480967/Watching-the-watchers-emperor-cichlids-can
Sci-comm post - https://phys.org/news/2026-03-fish-species.html

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Shun Satoh, Ryo Hidaka, Ryoichi Inoue; Watching the watchers: emperor cichlids can perceive attention towards their offspring by divers. R Soc Open Sci. 1 March 2026; 13 (3): 251919. https://doi.org/10.1098/rsos.251919

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
Gaze is a pivotal signal in animal societies, shaping not only predator avoidance but also social interaction. However, research remains scarce across many groups, limiting broad comparisons of gaze sensitivity among vertebrates. In this study, we examined whether the gaze of human divers directed towards the eggs (or fry) guarded by parental emperor cichlids 𝐵𝑜𝑢𝑙𝑒𝑛𝑔𝑒𝑟𝑜𝑐ℎ𝑟𝑜𝑚𝑖𝑠 𝑚𝑖𝑐𝑟𝑜𝑙𝑒𝑝𝑖𝑠—one of the largest cichlid species—altered aggressive behaviour towards divers. Emperor cichlids attacked divers significantly more often when divers looked directly at the eggs than when they averted their gaze or turned their fins towards the clutch, and the attack rate was similar to when divers stared at the guarding parents. Conversely, the time fish spent near divers was greatest when divers oriented their fins towards the eggs. These findings suggest that fish may possess a rudimentary form of ‘attention attribution’—the ability to recognize where another individual’s focus lies. Consequently, we may need to account for the role of ‘gaze’ in shaping wildlife responses within ecotourism and conservation contexts.

𝗣𝗵𝗼𝘁𝗼 𝗖𝗿𝗲𝗱𝗶𝘁
Emperor cichlid (𝐵𝑜𝑢𝑙𝑒𝑛𝑔𝑒𝑟𝑜𝑐ℎ𝑟𝑜𝑚𝑖𝑠 𝑚𝑖𝑐𝑟𝑜𝑙𝑒𝑝𝑖𝑠), Lake Tanganyika. Male (left) and female (right) breeders with free-swimming fry. The parents display an aggressive response towards the experimenter by flaring their gill covers. Photo by Ryo Hidaka.

Copyright © 2026 the Author(s). Published in the Royal Society Open Science journal. This paper is released under a Creative Commons Attribution 4.0 International (CC-BY-4.0) licence. https://creativecommons.org/licenses/by/4.0/

17/03/2026

Adult frogs and toads are well known for their acoustic communication and fascinating calls, but in recent decades, research has discovered tadpoles might also have something to say. Protázio et al. (2025) documented Ceratophrys joazeirensis (Caatinga Horned Frog) tadpoles producing a short, metallic click sound. Other studies have noticed sound production in other macrophagous and carnivorous tadpole species, and it appears to have evolved convergently in Ceratophrys and Gephyromantis clades. The function of these tadpole sounds is unclear but hypotheses include functions related to aggressive signalling during feeding or a defense mechanism against predation by conspecific tadpoles. The observations by the authors indicate a potential association with prey capture behavior. Their work introduces research questions to identify why tadpoles are making these sounds and whether there are more “singing” tadpoles to discover!

Link to Species of the Week: https://amphibiaweb.org/cgi/amphib_query?where-genus=Ceratophrys&where-species=joazeirensis

Leer en Español: https://bioweb.bio/faunaweb/amphibiaweb/Noticias

Link to Protázio et al. 2025: https://www.mapress.com/zt/article/view/zootaxa.5584.2.9/55555

12/03/2026

How long do wild sea turtles take to heal? From over 7200 photo-ID sightings, green turtles recover from anthropogenic injuries slowly, averaging 1.5 years, longer for severe trauma. Recurring propeller strikes and fishing line entanglements at Liuqiu Island, Taiwan, highlight the need for go-slow zones and responsible fishing. https://bit.ly/esr01472

12/03/2026

Understanding habitat preference is key to saving the critically endangered Chinese alligator. Our new research on captive alligators reveals their strong nest-site preferences: avoiding high banks and steep slopes in favor of accessible, flat areas. These findings help optimize breeding habitats to support conservation efforts. . https://bit.ly/esr01476

26/02/2026

𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠, a new species of Asian bumblebee catfish, is described from the Lenya River drainage in southern Myanmar. This represents the eighth species of 𝐴𝑘𝑦𝑠𝑖𝑠 recorded from Myanmar.

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠, a new species of catfish from southern Myanmar (Actinopterygii: Siluriformes: Akysidae)

Paywall - https://mapress.com/zt/article/view/zootaxa.5760.5.6

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Ng, H.H. & Kottelat, M. (2026) 𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠, a new species of catfish from southern Myanmar (Actinopterygii: Siluriformes: Akysidae). Zootaxa, 5760 (5), 583–589. https://doi.org/10.11646/zootaxa.5760.5.6

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠, a new species of catfish, is described from the Lenya River drainage in southern Myanmar.

It is distinguished from congeners in Myanmar by the color pattern of the body and caudal fin, as well as morphometry. 𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠 differs from congeners outside of Myanmar by pectoral-spine morphology and the color pattern of the body.

This represents the eighth species of 𝐴𝑘𝑦𝑠𝑖𝑠 recorded from Myanmar.

𝗘𝘁𝘆𝗺𝗼𝗹𝗼𝗴𝘆
The specific epithet is a compound of the Greek ποικίλος meaning “spotted” and οὐρά meaning “tail”. The name is used in reference to the hyaline spots on the proximal third of the caudal-fin lobes, which is one of the diagnostic characters for this species.

𝗣𝗵𝗼𝘁𝗼 𝗖𝗿𝗲𝗱𝗶𝘁
𝐴𝑘𝑦𝑠𝑖𝑠 𝑝𝑜𝑒𝑐𝑖𝑙𝑢𝑟𝑢𝑠, MHNG 2812.033, holotype, 30.8 mm SL; Myanmar: Lenya River drainage. Dorsal, lateral and ventral views.

Copyright © 2026 the Author(s). Published in the Zootaxa journal.

26/02/2026

Reposting this great opportunity to contribute to research on fish welfare in the hobby. If you are in the UK please do consider signing up, research like this is important, especially nowadays as the hobby faces pressures from multiple angles.

Thank you to those UK fishkeepers who have already taken part, getting as large a pool of participants though is important, please consider making the time to take part, if you already have not!

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A great opportunity for UK fishkeepers to take part in a study by the University of the West of Scotland in collaboration with the WALTHAM Petcare Science Institute (Mars Petcare), which aims to develop a novel, non-invasive method of behavioural assessment for ornamental fish. Participation will contribute to research, which could result in a significant improvement of fish welfare in the ornamental trade. A worthy study to get involved with!

𝗜𝗺𝗽𝗿𝗼𝘃𝗶𝗻𝗴 𝘄𝗲𝗹𝗳𝗮𝗿𝗲 𝗺𝗼𝗻𝗶𝘁𝗼𝗿𝗶𝗻𝗴 𝗳𝗼𝗿 𝗳𝗶𝘀𝗵 𝗶𝗻 𝘁𝗵𝗲 𝗼𝗿𝗻𝗮𝗺𝗲𝗻𝘁𝗮𝗹 𝘁𝗿𝗮𝗱𝗲

You are invited to take part in a study by the University of the West of Scotland in collaboration with the WALTHAM Petcare Science Institute (Mars Petcare), which aims to develop a novel, non-invasive method of behavioural assessment for ornamental fish.

We are looking for anyone living in the UK over the age of 18 with basic experience as an aquarium hobbyist, to take part in the final stage of this behavioural assessment study. We are not looking for expert and/or very experienced hobbyists. As part of the study, we are asking for a small amount of your time in which you will be observing the behaviour of a common species of ornamental fish.

Participation will contribute to research, which could result in significant improvement of fish welfare in the ornamental trade.

𝗔𝗯𝗼𝘂𝘁 𝘁𝗵𝗶𝘀 𝘀𝘁𝘂𝗱𝘆:

• You will receive all the necessary information before you begin.
• You will be watching a series of short video clips and identifying different behaviours.
• The whole process will transpire over the course of two separate weeks; however, the time it will take for you to take part will not be longer than 2 hours.

𝗧𝗼 𝗿𝗲𝗴𝗶𝘀𝘁𝗲𝗿 𝘆𝗼𝘂𝗿 𝗶𝗻𝘁𝗲𝗿𝗲𝘀𝘁, 𝗽𝗹𝗲𝗮𝘀𝗲 𝗰𝗼𝗻𝘁𝗮𝗰𝘁 𝘁𝗵𝗲 𝗳𝗼𝗹𝗹𝗼𝘄𝗶𝗻𝗴 𝗿𝗲𝘀𝗲𝗮𝗿𝗰𝗵𝗲𝗿:

Alexander Addison Marcos
Email: [email protected]

We hope that you will take the time to contribute to this research and thank you in advance for your participation!

23/02/2026

Different Colours, Different Outcomes: Interesting study on how environmental conditions play a critical role in shaping fish physiology and behaviour, with tank colour emerging as a relevant yet often overlooked factor in aquaculture and experimental research, as well as in the aquarium hobby.

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
Different Colours, Different Outcomes: Tank Colour Shapes Larval Survival, Growth, and Endocrine Response in 𝐶𝑖𝑐ℎ𝑙𝑎𝑠𝑜𝑚𝑎 𝑑𝑖𝑚𝑒𝑟𝑢𝑠

Open-access - https://www.mdpi.com/2076-2615/16/3/466

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Beriotto, A. C., Di Yorio, M. P., Sallemi, J. E., Alvarez-González, C. A., & Vissio, P. G. (2026). Different Colours, Different Outcomes: Tank Colour Shapes Larval Survival, Growth, and Endocrine Response in 𝐶𝑖𝑐ℎ𝑙𝑎𝑠𝑜𝑚𝑎 𝑑𝑖𝑚𝑒𝑟𝑢𝑠. Animals, 16(3), 466. https://doi.org/10.3390/ani16030466

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
Early environmental conditions play a critical role in shaping fish physiology and behaviour, with tank colour emerging as a relevant yet often overlooked factor in aquaculture and experimental research.

This study investigated how rearing tank colour affects larval performance in the cichlid fish 𝐶𝑖𝑐ℎ𝑙𝑎𝑠𝑜𝑚𝑎 𝑑𝑖𝑚𝑒𝑟𝑢𝑠. Larvae were reared in white, light-blue, or grey tanks, and survival, growth, pigmentation, s*x ratio, skeletal development, and the endocrine responses of somatolactin (Sl) and growth hormone (Gh) were evaluated. Survival was significantly lower in white tanks.

Conversely, larvae reared in white tanks reached a higher final body weight, while total length showed a similar but non-significant trend. Gh-immunoreactive cells exhibited significantly larger nuclear areas in larvae reared in white tanks and a tendency toward smaller cytoplasmic areas compared with those from light-blue tanks. Melanophore number did not differ among treatments, whereas larvae from grey tanks showed a higher number of Sl-immunoreactive cells. S*x ratios tended to be female-biased in white tanks. Skeletal development did not differ among tank colours and followed the expected chondrogenesis and ossification sequence.

Overall, tank colour influenced multiple aspects of larval development, particularly survival, growth, and endocrine responses, underscoring its relevance in fish rearing and experimental design.

𝗣𝗵𝗼𝘁𝗼 𝗖𝗿𝗲𝗱𝗶𝘁
Not from research. Screenshot from Lowell’s Fish Lab video on his excellent 3D printed fry tray. https://www.youtube.com/watch?v=16aFdagCLGk

Copyright © 2026 the Author(s). Published in the Animals journal. This paper is released under a Creative Commons Attribution 4.0 International (CC-BY-4.0) licence. https://creativecommons.org/licenses/by/4.0/