CORAL PURPLE PENCIL FISH – 紫焰铅笔

Nannostomus rubrocaudatus is similar to and closely related to Nannostomus marginatus and Nannostomus mortenthaleri.

They differ from them in that adult males have a bright purplish-red color between the dark stripes on their sides. The middle dark stripe extends to the base of the anal fin. The dorsal fin is predominantly red in the males, in the females it is a smaller red spot.

Nannostomus marginatus is clearly distinguished from the other two in that it lacks the red color on the males’ bodies, but N. mortenthaleri and N. rubrocaudatus are less easily distinguished.

Males of N. rubrocaudatus differ from those of N. mortenthaleri in that the red pigmentation in the back half of the body is more purplish and uniform than in N. mortenthaleri where, outside spawning season, the red color is only seen between the primary and secondary stripe.

In the females of N. rubrocaudatus, the spacing between primary and secondary stripes is silvery with a reddish stripe below the primary black stripe at the back of the body.

Like the other Nannostomus species, they have a different color pattern during the night, with the colors fading considerably and the dark stripes disappearing.

They are definitely schooling fish. The maximum size is approximately 4 centimeters.