Emerald rockcod
species of fish
The emerald rockcod (Trematomus bernacchii), also known as the emerald notothen, is a species of marine ray-finned fish belonging to the family Nototheniidae, the notothens or cod icefishes. It is native to the Southern Ocean
Taxonomy
The Emerald rockcod was first formally described in 1902 by the Belgian-born British ichthyologist George Albert Boulenger with the type localities given as Cape Adare in Antarctica at a depth of 5–8 fathoms and Duke of York Island at a depth of 3–4 fathoms. In 1982 the Russian ichthyologist Arkadii Vladimirovich Balushkin placed this species, and all the other species in its genus bar the type species, T. newnesi, in the new genus Pseudotrematomus but this has not been widely accepted.
Etymology
The specific name honours the Australian physicist and astronomer Louis Bernacchi who carried out much of the exploring and collecting of specimens during the Southern Cross Expedition, on which the type was collected.
Description
The emerald rockcod has a moderately compressed body and short snout. It is typically light brown or pinkish-brown, with darker coloring on the dorsal side. Its bodies are banded or spotted, either with dark brown or black. Its dorsal and anal fins are light brown, while its pectoral fins are dark brown with light spots. It has a series of three green spots around the base of the pectoral fins. Emerald rockcod have a short first dorsal fin with 4–6 spines and a long second dorsal fin with 34–39 soft rays that runs from about the center of the body to near the caudal fin.
“Emerald rockcod” enters the record as species of fish. Crown Archives preserves that source wording while asking what Emerald, rockcod and species can confirm, complicate or overturn.
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“Emerald rockcod” is worth following because a concise public description often conceals a longer documentary argument. Here, Emerald, rockcod and species provides the most credible route into that argument.
Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Aug 18, 2026. The linked authority identifier is Q600785. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1902 and 1982.
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This entry incorporates text from “Emerald rockcod” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.