Diamond Tropical Aquatics

08/02/2023

Scientists officially describe the world's largest cavefish as 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟. Discovered in 2019 and tentatively identified as a troglomorphic form of the golden mahseer, 𝑇𝑜𝑟 𝑝𝑢𝑡𝑖𝑡𝑜𝑟𝑎. Detailed analyses now reveal that it is a new species of the genus 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠, the sister taxon of 𝑇𝑜𝑟.

Open-access - https://vertebrate-zoology.arphahub.com/article/101011/

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
The world’s largest cave fish from Meghalaya, Northeast India, is a new species, 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 (Cyprinidae, Torinae)

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Dahanukar N, Sundar RL, Rangad D, Proudlove G, Raghavan R (2023) The world’s largest cave fish from Meghalaya, Northeast India, is a new species, 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 (Cyprinidae, Torinae). Vertebrate Zoology 73: 141-152. https://doi.org/10.3897/vz.73.e101011

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
The world’s largest subterranean fish was discovered in 2019, and was tentatively identified as a troglomorphic form of the golden mahseer, 𝑇𝑜𝑟 𝑝𝑢𝑡𝑖𝑡𝑜𝑟𝑎. Detailed analyses of its morphometric and meristic data, and results from molecular analyses now reveal that it is a new species of the genus 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠, the sister taxon of 𝑇𝑜𝑟.

We formally describe the new species as 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟, honouring the tribal communities of East Jaintia hills in Meghalaya, Northeast India, from where it was discovered. 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 possesses a number of characters unique among species of 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠, with the exception of the similarly subterranean 𝑁. 𝑠𝑢𝑏𝑡𝑒𝑟𝑟𝑎𝑛𝑒𝑢𝑠 from Thailand. The unique characters that diagnose 𝑁. 𝑝𝑛𝑎𝑟 from all epigean congeners comprise highly reduced eye size to complete absence of externally visible eyes, complete lack of pigmentation, long maxillary barbels, long pectoral-fin rays, and scalation pattern.

𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 is distinguished from the hypogean 𝑁. 𝑠𝑢𝑏𝑡𝑒𝑟𝑟𝑎𝑛𝑒𝑢𝑠, the type locality of which is a limestone cave ~2000 kms away in Central Thailand, by a lesser pre-pelvic length (47.8–49.4 vs. 50.5–55.3 %SL), a shorter caudal peduncle (16.1–16.8 vs. 17.8–23.7 %SL), and shorter dorsal fin (17.4–20.8 vs. 21.5–26.3 %SL).

In addition, 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 is also genetically and morphologically distinct from its close congeners with a raw genetic divergence of 1.1–2.7% in the COI gene with putative topotype of 𝑁. ℎ𝑒𝑥𝑎𝑠𝑡𝑖𝑐ℎ𝑢𝑠 and 2.1–2.6% with putative topotype of 𝑁. ℎ𝑒𝑥𝑎𝑔𝑜𝑛𝑜𝑙𝑒𝑝𝑖𝑠.

𝗘𝘁𝘆𝗺𝗼𝗹𝗼𝗴𝘆
The species name 𝑝𝑛𝑎𝑟, honours the 'pnar', the sub-tribal group of the Khasi people in the state of Meghalaya, India.

𝗜𝗺𝗮𝗴𝗲
Live images of 𝑁𝑒𝑜𝑙𝑖𝑠𝑠𝑜𝑐ℎ𝑖𝑙𝑢𝑠 𝑝𝑛𝑎𝑟 in their habitat from Krem Um Ladaw (Photos A, B, C: Uros Aksamovic, D: Dan Harries).

Vertebrate Zoology / papers authors © - Paper released under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence.
https://creativecommons.org/licenses/by/4.0/

21/11/2022

https://www.ni.bio.br/1982-0224-2022-0067/
https://doi.org/10.1590/1982-0224-2022-0067

19/11/2022

Thanks to Keny Kanagusuku for this new open access paper.

Valderrama-Herrera, M. & Kanagusuku, K. & Ramírez-Amaro, S. 2022 Morphological abnormalities in the Chilean Eagle ray chilensis (Myliobatiformes: Myliobatidae) off the Peruvian coast, Southeast Pacific. Universitas Scientiarum, 27(3), 292–312
https://revistas.javeriana.edu.co/index.php/scientarium/article/view/34726

Records about morphological abnormalities in rays of the genus Myliobatis are scarce worldwide. In the present study, three specimens exhibiting different malformations were identified during the monitoring of the reproductive biology of the Chilean eagle ray Myliobatis chilensis, conducted from 2017 to 2018 in the fishing port of Salaverry (northern Peru). The identified specimens included: (i) a female with split pectoral fins, (ii) a male with an unfused-to-the-head pectoral fin, and (iii) a female with a short and thick tail. Here we report and discuss the implications and likely causes of these first three cases of morphological abnormalities in M. chilensis from the western Pacific.

image by the authors: MC01-2018: Immature female specimen with divided pectoral 昀椀ns. (a) Dorsal and (b) ventral views. In
the radiography (c), pectoral radial fusion is shown; this could be similar to the crurae located in the pelvic 昀椀ns.

29/07/2022

A second species of Bowfin has been recognised - 𝐴𝑚𝑖𝑎 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎. Originally described from Lake Huron in 1836, only to be later thought a synonym of 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎. New scientific tools and methods (and a lot of work by the researchers) now indicate the original description as a separate species was correct, and 𝐴𝑚𝑖𝑎 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 is a valid species.

Open-access (Preprint) - https://www.biorxiv.org/content/10.1101/2022.07.25.500718v1

For over 150 years, the Bowfin has been considered one species - 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎, despite its wide geographic range across different major river systems in North America.

Researchers now confirm two major lineages in 𝐴𝑚𝑖𝑎; one includes specimens from the type locality of 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 in Charleston, South Carolina, USA and the other corresponds to a lineage for which the oldest available name is 𝐴𝑚𝑖𝑎 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 Richardson 1836 from Lake Huron in Ontario, Canada.

𝗪𝗵𝗮𝘁 𝗶𝘀 𝗮 𝗣𝗿𝗲𝗽𝗿𝗶𝗻𝘁 𝗣𝘂𝗯𝗹𝗶𝗰𝗮𝘁𝗶𝗼𝗻?
https://www.biorxiv.org/content/what-unrefereed-preprint

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
Hidden species diversity in a living fossil vertebrate

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Hidden species diversity in a living fossil vertebrate. Chase D Brownstein, Daemin Kim, Oliver D Orr, Gabriela M Hogue, Bryn H Tracy, M Worth Pugh, Randall Singer, Chelsea Myles-McBurney, Jon Michael Mollish, Jeffrey W Simmons, Solomon R David, Gregory Watkins-Colwell, Eva A Hoffman, Thomas J Near. bioRxiv 2022.07.25.500718; DOI: https://doi.org/10.1101/2022.07.25.500718

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
Ancient, species-poor lineages persistently occur across the Tree of Life. These evolutionarily unique lineages are likely to contain unrecognized species diversity masked by the low rates of morphological evolution that characterize living fossils.

Halecomorphi is a major clade of ray-finned fishes that diverged from its closest relatives over 200 million years ago yet is represented by only one recognized living species in eastern North America, the Bowfin 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎.

Here, we use double digest restriction-site associated DNA (ddRAD) sequencing and high-resolution computed tomography to illuminate recent speciation in the bowfins.

Our results support the resurrection of a second living species of Bowfin with the timing of diversification dating to the Pleistocene. In turn, we expand the species diversity of an ancient lineage that is integral to studies of vertebrate genomics and development, yet is facing growing conservation threats driven by the caviar fishery.

𝗜𝗺𝗮𝗴𝗲
Top: Beautiful photo of 𝐴𝑚𝑖𝑎 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎
https://www.toddamacker.com/
https://www.instagram.com/toddamacker/

Bottom: Identification of a hidden Bowfin species diversity. (a) Map of eastern North America showing occurrences of 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 (blue) and 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 (yellow). Stars indicate type localities. Diamonds indicate specimens sampled in our ddRAD phylogenetic analysis. (b) Phylogeny and genomic structure analysis of 177 specimens of 𝐴𝑚𝑖𝑎 based on 56,247 ddRAD loci, showing genomic ancestry and reciprocal monophyly of both 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 and 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎. Photograph of 𝐴𝑚𝑖𝑎 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 from lower Tennessee River, Marshall Co., Alabama USA YPM 035200 by JMM and Amia calva from the Suwanee River, Gilchrist Co., Florida USA UF 238466 by Zachary Randall. (c) Comparison of pairwise Fst values for comparisons within each species and the comparisons between 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 and 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎. (d) Boxplot showing interopercle robusticity (ratio between maximum dorsoventral depth and maximum anteroposterior length) in 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 and 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎. The long lower tail on the 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 boxplot is created by the inclusion of a juvenile specimen; ontogenetically mature individuals do not overlap. CT-scanned skull of 𝐴𝑚𝑖𝑎 𝑐𝑎𝑙𝑣𝑎 is TU 22613; CT-scanned skull of 𝐴. 𝑜𝑐𝑒𝑙𝑙𝑖𝑐𝑎𝑢𝑑𝑎 is TU 118772.

18/07/2022

NEW SPECIES 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑚𝑖𝑘𝑜𝑙𝑗𝑖𝑖

Today to this beautiful family. A new species has been added. It is good news

Congratulations Ivan Mikolji !

𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑚𝑖𝑘𝑜𝑙𝑗𝑖𝑖, a beautiful new species of Oscar cichlid from the Orinoco River and the Gulf of Paria basins in Venezuela and Colombia. Previously referred to as 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑠𝑝. Lasso and 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑐𝑓. 𝑜𝑐𝑒𝑙𝑙𝑎𝑡𝑢𝑠 by researchers and in imports to the hobby. This species was named to honor Ivan Mikolji, Venezuelan explorer, artist, author, and photographer.
Open-access - https://zookeys.pensoft.net/article/81240/
Check out Ivan's award-winning book - Fishes of the Orinocco in the Wild - https://www.mikolji.com/.../fishes-of-the-orinoco-in-the.../
𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
A new species of 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 (Teleostei, Cichlidae) from the Orinoco River and Gulf of Paria basins, northern South America
𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Lozano AP, Lasso-Alcalá OM, Bittencourt PS, Taphorn DC, Perez N, Farias IP (2022) A new species of 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 (Teleostei, Cichlidae) from the Orinoco River and Gulf of Paria basins, northern South America. ZooKeys 1113: 111-152. https://doi.org/10.3897/zookeys.1113.81240
𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
Based on morphological and molecular analysis of Astronotus species, a new species is described from the Orinoco River and Gulf of Paria basins in Venezuela and Colombia.
Morphologically, it differs from 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑐𝑟𝑎𝑠𝑠𝑖𝑝𝑖𝑛𝑛𝑖𝑠 and 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑜𝑐𝑒𝑙𝑙𝑎𝑡𝑢𝑠 in pre-orbital depth, caudal peduncle depth, head width, and caudal peduncle length, with significant differences in average percentage values. Osteologically, it differs from the two described species by lacking a hypurapophysis on the parahypural bone (hypural complex) and having two or three supraneural bones. Another characteristic that helps diagnose the new species is the morphology of the sagitta otolith, which is oval with crenulated dorsal and ventral margins and a rounded posterior edge.
Genetically, the new species is distinct from all the other lineages previously proposed for the genus, delimited by five single locus species delimitation methods, and also has unique diagnostic nucleotides. Phylogenetic analyses support the monophyly of the new species as well as all other species/lineages. 𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 species have considerable genetic, anatomical, and sagitta otolith shape differences, but have few significant traditional morphometric and meristic differences, because there is high variability in counts of spines, soft dorsal-fin rays, and lateral-line scales.
It is clear that this new species is genetically and anatomically differentiated from all other species within the genus, and deserves recognition as a new valid species.
𝗘𝘁𝘆𝗺𝗼𝗹𝗼𝗴𝘆
The specific name is given to honor Mr. Ivan Mikolji, Venezuelan explorer, artist, author, underwater photographer, and audiovisual producer, in recognition for being a tireless and enthusiastic diffuser of the biodiversity and natural history of freshwater fishes, conservation of aquatic ecosystems of Venezuela and Colombia, and for logistic support for this work. Since 2020, Ivan Mikolji has been recognized as Associate Researcher of the Museo de Historia Natural La Salle, from the Fundación La Salle de Ciencias Naturales, in Caracas, Venezuela.
𝗜𝗺𝗮𝗴𝗲
𝐴𝑠𝑡𝑟𝑜𝑛𝑜𝑡𝑢𝑠 𝑚𝑖𝑘𝑜𝑙𝑗𝑖𝑖 sp. nov.
A) Live coloration of specimens collected with holotype.
B) Natural shallow pond and type locality in floodplain of Arauca River Venezuela.
Photographs by Ivan Mikolji - https://www.mikolji.com/

10/07/2022

Description of a new species of miniature catfish of the genus Ammoglanis (Siluriformes: Trichomycteridae) from rio Tapajós basin, Brazil.

Canto, A.L.C., Hercos, A.P. & Ribeiro, F.R.V. (2022)

Ammoglanis nheengatu Canto et al., 2022

https://www.scielo.br/j/ni/a/spN9zvJZBbvYsGvYQtWRYVq/?lang=en #

Etymology. The specific epithet, nheengatu, honors the indigenous people of the Amazon. Nheengatu is known as the general language of the Amazon that helped create the cultural identity of the largest Brazilian region. In the nineteenth century Nheengatu was the most commonly spoken language in the Amazon region, in both small and large cities (e.g., Belém, Manaus, Macapá, Santarém, Tefé, and Óbidos). Currently, Nheengatu is being rescued in indigenous schools of the lower rio Tapajós basin. A noun in apposition.

Figure: Ammoglanis nheengatu in lateral and dorsal views, holotype, INPA 59653, 14.8 mm SL, igarapé Branco, tributary to rio Aruri Grande, rio Jamanxim drainage, rio Tapajós basin, Pará State, Brazil.

10/07/2022

https://www.ni.bio.br/1982-0224-2022-0002/
https://doi.org/10.1590/1982-0224-2022-0002

29/06/2022

23/06/2022

21/06/2022

Via Wonders of the Mekong - At 661 pounds, this giant freshwater stingray (𝑈𝑟𝑜𝑔𝑦𝑚𝑛𝑢𝑠 𝑝𝑜𝑙𝑦𝑒𝑝𝑖𝑠) just dethroned the Mekong giant catfish to become the world's largest freshwater fish (by weight)!

https://www.bbc.co.uk/news/world-asia-61862169

https://en.wikipedia.org/wiki/Giant_freshwater_stingray

Image: Chea Seila Wonders of the Mekong
Please note this fish was released after capture.