Halichoeres nigrescens. Credit: RVS Fishworld Inc
Oftentimes, a species’ abundance in the wild doesn’t necessarily translate to its abundance in the aquarium trade—for instance, Halichoeres nigrescens. Despite being one of the most ubiquitous fishes of nearshore, weedy habitats, this hearty and attractive wrasse is almost entirely ignored by the fishkeeping community. Thankfully, the fine folks at RVS Fishworld have procured a stunning specimen illustrating the full aesthetic potential this wrasse has to offer.
Easily identified when you know what to look for. Credit: RVS Fishworld Inc
In keeping with this fish’s mix of obscurity and abundance, there are a great many common names by which it is known: the Pinstripe Wrasse, Bubblefin Wrasse, Diamond Wrasse, Green-back Wrasse, and White-button Wrasse. This latter appellation is my favorite of the bunch, as it references the distinctive white lateral markings seen in females.
This female clearly shows the sooty back and white spots of the species. Credit: Keido Uchino
There has been a tremendous amount of taxonomic confusion surrounding what is and isn’t “Halichoeres nigrescens”, as quite a few superficially similar species share its red and green patterning. It can be quite challenging remembering them all, which is why I created an identification guide to help in diagnosing this group (which I totally had to use to identify the specimen in this article). Adding to the confusion is the uncertainty as to whether this fish, which ranges from the African coastline through the West Pacific, is truly a single species or a pair of geminate sister taxa split into Indian Ocean and Pacific populations. In the latter scenario, H. dussumieri is the correct nomenclature for those found in the Indian Ocean. This awaits genetic confirmation, but be aware that both names are widely in use by various authors.
The red along the body appears to be highly variable. Credit: ぶー
Identification of this species can be challenging, as it is rather non-descript for its genus. Males and females possess separate patterns. Females sport a prominent black spot in the soft rays of the dorsal fin and have a lightly colored belly set off sharply against a thick lateral band running across the midline of the body. Often there is a distinctive row of white spots along the midline, though, to some extent, these appear to be behaviorally controlled.
The post Rarely Seen Halichoeres nigrescens Collected in Philippines appeared first on Reefs.com.