Gobiodon bilineatus Herler, Bogorodsky & Suzuki, 2013

Gobiodon bilineatus Herler, Bogorodsky & Suzuki, 2013 View in CoL : Two-Lined Coralgoby

Synonyms or described as: No recorded synonyms.

Description: Gobiodon bilineatus has two colour variants throughout its life history, juvenile and adult ( Herler, Bogorodsky and Suzuki, 2013). Juveniles are typically translucent reddish or greenish in colour with five vertical blue lines across their facial region. Two of these lines pass through the eye on either side, extending down the cheek, and the other three occupy the region leading up the pectoral fin base, where the last line resides. Adults are usually uniformly orange red in colour with only the two blue lines that pass on either side of the eye pupil, with the other lines seen in juveniles fading significantly, and completely missing in larger adults ( Figure 8 View FIGURE 8 ). Smaller adults may still have remnants of the juvenile lines between the eye and the pectoral fin ( Herler, Bogorodsky and Suzuki, 2013). A pale slightly blue coloured band can sometimes be observed running along the base of the dorsal fins.

Distribution: Gobiodon bilineatus has currently only been observed in the Gulf of Aqaba and throughout the Red Sea ( Herler, Bogorodsky and Suzuki, 2013).

Habitat: Gobiodon bilineatus has been frequently observed inhabiting the corymbose corals A. samoensis and A. secale (Studer, 1878) , and the digitate A. gemmifera at lower frequencies.

Status: The IUCN has recorded the population status for G. bilineatus as ‘Least Concern’ on the Red List ( Larson, 2019b).

Sociality: There have been no known studies describing the sociality of this species at this stage.

Genetics: Gobiodon bilineatus has been included in one genetic study ( Herler, Bogorodsky and Suzuki, 2013), where the closest genetic relation was G. quinquestrigatus , closely followed by G. spadix and G. rivulatus . Gobiodon reticulatus and G. irregularis can also be observed in this clade. Specimens that shared similar characteristics as G. bilineatus from the Maldives and Taiwan were also included in and are situated next to the confirmed species from the Red Sea on the phylogenetic tree displayed in Herler, Bogorodsky and Suzuki (2013).