By: Dana Sackett
Each year brings new discoveries of organisms we had no idea we shared the Earth with. Some of these discoveries, particularly those in the aquatic environment (though I may be a bit bias), can leave people scratching their heads in wonder. In 2001, an international project called the All Species Inventory was started with the ambitious goal of identifying every organism on Earth in the following 25 years. Thus far, scientists have identified approximately 1.7 million different species. While this seems like an amazing number, it is estimated that 90% of life on Earth still remains undiscovered.
With so many species yet to be discovered we will likely be gasping in wonder at new creatures each year for a long time to come. These discoveries reawaken the awe and intrigue of the natural world and the realization that the diversity of life is extraordinary! In honor of these newly discovered creatures, we at The Fisheries Blog would like to highlight a select few of these recent discoveries.
1. The Greek goddess fish: Deep beneath the surface of the ocean around an isolated and remote Brazilian archipelago, scientists discovered a vibrant and beautiful fish. So eye catching in fact, the scientist who found it did not notice a sixgill shark hovering directly above (see video below; note the high pitch of their voices is due to the need to use helium at that depth, but it could also be their excitement). Named after Aphrodite, the Greek goddess of beauty, Tosanoides Aphrodite, is, as of now, the only fish of its kind in the Atlantic Ocean.
2. The Black Panther fish: Cirrhilabrus Wakanda is another recent and colorful discovery that was named after the fictional African country of Wakanda. When first seen, the tough, vibrant purple scales struck the researcher as resembling the suit of the Marvel superhero Black Panther. This new species at 6cm in length was discovered in waters around 250ft (75m) in the western Indian Ocean and has been included in the group of fairy wrasses found from the East Coast of Africa through the Central Pacific Ocean.
3. The cat-eyed fish:Another dramatic addition is a newly described cat-eyed cardinalfish species less than an inch in length (~20mm). This species along with other members of this cardinalfish group have bioluminescent or light-reflecting organs on each side of its body, feed at night on plankton or small fish, and the males hold developing young in their mouths until they are ready to be released into the world. The distinguishing factor of this newly discovered species is that it has a very distinct “cat’s eye” that is created by a black bar through the eye with white crescents covering the rest of the eye. Discovered in relatively shallower depths (8-12m) than some other recent discoveries off the coast of Papua New Guinea, it has translucent pale pink to reddish orange body with a dense covering of variable-sized orange spots on the head and anterior body.
4. Fishes of the abyss: With each new dive into the deepest darkest depths of the Earth, newly discovered snailfish are testing the limits of our assumptions that few fish could exist as such depths. It is estimated that fish cannot physiologically survive below 27,000ft (8,200m). The Marians snailfish (Pseudoliparis swirei) is testing that limit, earning it the title of “deepest dwelling fish.” A recent recording of the small tad-pole sized (~4 inches, 112mm) gelatinous fish showed that it could inhabit depths below 26,600ft. Here they dominate as top-predators feeding on invertebrates. With each new dive it seems that our deepest trenches are home to more different species of these small gelatinous fish species. Indeed, a more recent discovery of a new species of snailfish was just discovered in the Atacama Trench just west of South America. With very few hard parts (these being their teeth and inner ear bones, which give them balance) and a gelatinous body, snailfish are perfectly adapted to living in the extreme pressure of these dark abysses. In fact, without the extreme pressure and cold of their environment to support their bodies they melt, which has been seen to happen when a specimen from the deep is brought to the surface.
5. The flashiest new signal fish: A vibrant and literally “flashy” new species of signalfish (Pteropsaron indicum) was recently discovered in the relatively deep (230ft or 70m) waters of the Lakshadweep sea off India. The bold yellow bands on its pale greyish pink body and long filamentous fins isn’t even the flashiest part of this species. The real action comes from the way these fish communicate with other members of its species: quickly flipping open and closed its brightly colored dorsal fin in an unmistakable signaling behavior.
6. The newest pygmy shark: Three new species of sharks that inhabit waters below 3000ft (915m) have been discovered in recent years. One in particular, the pygmy false catshark (Planonasus indicus) was recently found in the northern India Ocean where it was caught as bycatch in a deep-sea longlining fishery targeting another deepwater shark species, the gulper shark. This species is approximately 2ft in length and similar though physically distinct in several ways from another pygmy shark species (P. parini).
7. The teeniest pig seahorse: Ranging in size from a grain of rice to a jellybean and camouflaged so well that it has often been mistaken for a bit of floating seaweed, it is no wonder this tiny seahorse has remained elusive until just recently. Named the Japan pig seahorse (Hippocampus japapigu) because of its resemblance to a tiny baby pig. These tiny seahorses blend in perfectly with their shallow soft-coral and algae-covered rock habitat. While little is known about the species, citizen scientists have found a number in Taiwan, a potential source to find out more about these amazing creatures.
The species and ecosystems of our planet are all connected and reliant on each other. This point is particularly poignant given how many species remain unknown. With the current pace of climate change there is a serious concern many of these species may be lost before we ever knew they existed; and maybe more importantly, before we truly understand how they impact and support the ecosystems around them. Newly discovered species serve as an important reminder of the critical role we play in understanding and preserving these precious ecosystems and ultimately our planet as we currently know it (see here for an article on the value of a species).
References and additional resources:
Allen GR, Erdmann MV. 2019. Siphamia arnazae, a new species of cardinalfish (Teleostei: Apogonidae) from Papua New Guinea. Journal of the Ocean Science Foundation. 33:1-8.
Ebert DA, Akhilesh KV, Weighmann S. 2019. Planonasus indicus sp. n., a new species of pygmy false catshark (Chondrichthyes: Carcharhiniformes: Pseudotriakidae), with a revised diagnosis of the genus and key to the family. 49:1321-1341.
Gerringer ME, Linley TD, Jamieson AJ, Goetze E, Drazen JC. Pseudoliparis swirei sp. nov.: A newly-discovered hadal snailfish (Scorpaeniformes: Liparidae) from the Mariana Trench. Zootaxa 4358: 161-177.
Heard J, Chen J-P, Wen CKC. 2019. Citizen science yields first records of Hippocampus japapigu and Hippocampus denise (Syngnathidae) from Taiwan: A hotspot for pygmy seahorse diversity. Zookeys 883:83-90.
Pinheiro HT, Rocha C, Rocha LA. 2018. Tosanoides aphrodite, a new species from mesophotic coral ecosystems of St. Paul’s Rocks, Mid Atlantic Ridge (Perciformes, Serranidae, Anthiadinae). Zookeys 786:105-115.
Shepherd, B., Pinheiro, H.T., Phelps, T., Perez-Matus, A. & Rocha, L.A. (2019) Luzonichthys kiomeamea (Teleostei: Serranidae: Anthiadinae), a new species from a mesophotic coral ecosystem of Rapa Nui (Easter Island). Journal of the Ocean Science Foundation 33:17–27
Short G, Smith R, Motomura H, Harasti D, Hamilton H. 2018. Hippocampus japapigu, a new species of pygmy seahorse from Japan, with a redescription of H.pontohi (Teleostei, Syngnathidae). Zookeys 779:27-49. https://doi.org/10.3897/zookeys.779.24799
Tea Y-K, Pinheiro HT, Shepherd B, Rocha LA. 2019. Cirrhilabruswakanda, a new species of fairy wrasse from mesophotic ecosystems of Zanzibar, Tanzania, Africa (Teleostei, Labridae). Zookeys 863:85-96.
Victor B, Kumar AB. 2019. Pteropsaron indicum, a new species of signalfish (Teleostei: Trichonotidae: Hemerocoetinae) with a micro-CT analysis of osteology. Journal of Ocean Science Foundation. 33:70-78.
Yancey PH, Gerringer ME, Drazen JC, Rowden AA, Jamieson AA. 2014. Marine fish may be biochemically constrained from inhabiting the deepest ocean depths. PNAS 111:4461-4465. https://doi.org/10.1073/pnas.1322003111