Sicyopterus lagocephalus
species of fish
Sicyopterus lagocephalus, the red-tailed goby or blue stream goby, is a species of goby native to islands of the Indian Ocean from the Comoros to the Mascarene Islands to the Pacific Ocean where it reaches French Polynesia and can be found as far north as Japan. It is an amphidromous species: adults can be found in swift-flowing streams with rocky beds but the eggs hatch at sea and the larval stage remains in marine waters, migrating to freshwaters when they reach the postlarval stage. This species can reach a total length of 13 cm (5 in). In some places it is an important species for local consumption with the post-larvae being caught as they mass in estuaries.
Description
Male Sicyopterus lagocephalus can grow to a total length of about 13 cm (5.1 in) while females can reach 10.6 cm (4.2 in). The dorsal fin is divided in two and has 6 to 7 spines and 9 to 10 soft rays. The anal fin has a single spine and 10 soft rays. The pectoral fin has about 19 soft rays. During the rainy season, males become very colourful; the sides are metallic bluish-green, the tail is orange-red and there are about seven dark, saddle-shaped markings on the back. Females are grey or brown with dark saddle markings, a pale belly and a black and white band at the base of the tail.
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This entry incorporates text from “Sicyopterus lagocephalus” 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.