Factsheet 7

Danio roseus. Fang & Kottelat 2000¹

This is another of the beautiful ‘new’ Danio species we brought back from Fischhaus Zepkow. It is similar in appearance to Danio albolineatus but can be distinguished by its slimmer body, by having two pairs of long barbels and by lacking horizontal stripes along its flanks. Danio roseus is a spectacular looking fish. With a slight stretch of the imagination, it could be called the ‘Neon Danio’. The back and sides of the fish are a steely blue whilst the underside has a brilliant red colouration. This colouration is only evident when the fish are sexually mature; young fish are a just steely blue / silver. When in a shoal, in a well-planted tank, they are really beautiful. As with most Danios, they are very active fish – particularly at feeding time.

Danio roseus, is a native of N.E.Thailand and N.W.Laos although it is currently not listed as being found in Thailand 2. The holotype of the species, was collected in Nong Kai province in Thailand and paratypes in both Thailand and Laos. Fang Fang & Kottelat report this species as reaching about 35mm in SL. Adult fish in my possession, are larger.

Spawning was accomplished using the standard ‘net’ method and as with most Danios, they are very prolific. Using just two females and four males, resulted in a 200 plus batch of young fish.

Just six weeks from the egg stage, they reached about an inch in length (25mm) and were eating chopped tubifex worms and dried food several times a day. At this stage, they show little colouration. They were spawned in an 18 x 12 x 12 tank and were moved on to a 36 x 15 x 15 tank after one month. They are now in a 60 x 18 x 18 tank with external power filter. Water changes of approximately 20% are undertaken three or four times a week.

As this species is similar to Danio albolineatus , I would expect it to grow to a similar size (45mm. S/L).

References:

   1. Ichthyological Exploration of Freshwaters. Volume 11. No.2

   2. Check list of Freshwater Fishes of Thailand

© Pete Cottle, 2003. This fact sheet may not be reproduced in any form without the permission of the author.