Harlequin rasbora
The harlequin rasbora may be a fish that has associate or so lozenge-shaped body, whose basal color from the pinnacle to the caudal peduncle is associate orange-pink, the precise hue variable relying upon such factors as water conditions and therefore the original population from that the fish was obtained. The posterior 1/2 the body is overlaid with an outsized, roughly triangular black marking, that tapers toward the terminal finish of the caudal peduncle, and begins or so below the centre of the attachment of the fin (commonly referred to as a "black wedge"). In common with all cyprinids, the articulation of the pectoral and girdle fins follows a well-recognized pattern, the pectoral fins being placed at once posterior to the plate or gill cowl, while the girdle fins area unit placed how additional back on the ventral portion of the body, during this case virtually directly in an exceedingly vertical line drawn through the fin. This relationship between the pectoral and girdle fins is seen in characins also as cyprinids, associated may be a feature of all the ostariophysans (fishes possessing an auxiliary mechanism for police work sound consisting of a collection of internal bones referred to as the Weberian ossicles).
The dorsal, anal, caudal and girdle fins area unit all tinted red, the fin being forked, with the red color targeted within the outer rays, the inner section of the tail fin being additional hyaline.
It is attainable to confuse this fish with 2 similar species that were so originally thought of to be taxonomic group of T. heteromorpha, specifically Trigonostigma espei and Trigonostigma hengeli. These fishes area unit additional slender in body form than T. heteromorpha, and therefore the black marking, rather than being or so triangular, includes a horizontal stripe that tapers towards the caudal peduncle, and is greatly thickened and extended downwardly below the fin. thanks to this fishes with this marking area unit unremarkably called "lamb chop rasboras" thanks to its perceived likeness to the butchery cut called a lamb chop.
A fully mature individual harlequin rasbora attains a regular length of 2 inches (5 cm).
Males area unit cited as possessing a rather larger black body patch than females, with the section abutting the anal fin being additional rounded in males. Ripe females area unit perceptibly fuller in body define.
