Danio sondhii Hora & Mukerji, 1934; Brachydanio sondhii (Hora & Mukerji, 1934)
Described from a spring close to the town of Hopong, Taunggyi District, Shan state, eastern Myanmar which may also be the type locality of Danio margaritatus.
The habitat near Hopong is an area of permanently-flooded grassland formed by the damming of a spring for agricultural purposes and is around 1,040 metres AMSL.
Maximum Standard Length
40 – 45 mm.
Aquarium SizeTop ↑
Best kept in a densely-planted tank and an excellent choice for the carefully-aquascaped set-up. The addition of some floating plants to diffuse the light entering the tank also seems to be appreciated and adds a more natural feel.
Water movement does not need to be particularly strong as it mostly hails from sluggish waters though will also do well in a hill stream-type set-up provided torrent-like conditions are avoided.
Since it naturally occurs in pristine habitats it’s intolerant to accumulation of organic pollutants, requires more-or-less spotless water in order to thrive and should never be introduced to biologically immature aquaria.
Weekly water changes of 30-50% tank volume should be considered routine, and the tank must have a very tightly-fitting cover as it’s a particularly accomplished jumper and is prone to bouts of skittish behaviour.
Temperature: 20 – 26 °C
pH: 6.5 – 7.5; a value of 7.3 was recorded at the locality described above.
Hardness: The water in northern Myanmar is typically soft so aim for somewhere within the range 18 – 90 ppm.
A good quality dried product can be used as the staple diet but this should be supplemented with regular meals of small live and frozen fare such as bloodworm, Daphnia, Artemia, etc. for the best colouration and conditioning.
Behaviour and CompatibilityTop ↑
This species is peaceful and can be maintained alongside other fishes that appreciate similar conditions such as other small cyprinids.
Bottom-dwellers could include loaches from genera such as Lepidocephalichthys or Nemacheilus plus catfishes such as Akysis, Hara or Erethistes spp. Freshwater gobies like Rhinogobius or Stiphodon spp. and many freshwater shrimp should also work in well-oxygenated set-ups.
It’s a schooling species by nature and really should be kept in a group of at least 8-10 specimens. Maintaining it in decent numbers will not only make the fish less nervous but will result in a more effective, natural-looking display. Males will also display their best colours as they compete with one other for female attention.
Sexually mature females should be rounder-bellied, less colourful and a little larger than males.
Like most small cyprinids Devario spp. are egg-scattering free spawners exhibiting no parental care. When in good condition they will spawn often and in a well-planted, mature aquarium it’s possible that small numbers of fry may start to appear without intervention.
However if you want to maximise yield a more controlled approach is required. The adult group can still be conditioned together but a smaller tank with a base measuring around 45cm x 30cm should also be set up and filled with mature water.
This should be very dimly lit and the base covered with some kind of mesh of a large enough grade so that the eggs can fall through but small enough so that the adults cannot reach them.
The widely available plastic ‘grass’-type matting can also be used and works well, as does a layer of glass marbles. Alternatively filling much of the tank with a fine-leaved plant such as Taxiphyllum spp. or wool mops can also return decent results.
The water itself should be of slightly acidic to neutral pH with a temperature towards the upper end of the range suggested above. An air-powered sponge filter or air stone(s) should also be included to provide oxygenation and water movement.
When the adults are well-conditioned and the females appear gravid one or two pairs should then be introduced. If ready spawning usually taking place within 24 hours, signified by the female appearing noticeably slimmer. After 48 hours the adults should be removed whether spawning has occurred or not.
Incubation is temperature-dependant to an extent but typically lasts 24-36 hours with the young free-swimming a few days later. Initial food should be Paramecium or similar, introducing Artemia nauplii, microworm, powdered dry foods, etc. once the fry are large enough to accept them.
This species first appeared in the aquarium trade during the mid-2000s and there was some initial confusion surrounding its identity since it appears superficially similar to the sympatric Microrasbora cf. rubescens as well as the congener D. acuticephala. It’s easily-distinguished from both by the presence of a dark cleithral spot located posterior to the gill opening.
In recent years it’s become commonplace to refer to the stripes on the body and fins of danionins as follows:
- P stripe: or ‘pigment stripe‘ is the central, dark, lateral stripe on the body which extends into the caudal-fin in some species. Stripes above it are numbered P+1, P+2, etc. and those beneath P-1, P-2, P-3.
- A stripe: the central stripe on the anal-fin; the proximal stripe (above it) is A+1 and the distal stripe (beneath) A-1.
- D stripe: The submarginal dorsal-fin stripe.
Following Fang (2003) Devario spp. are characterised by: possession of a P stripe extending onto the median caudal-fin rays; a short maxillary barbel (absent in some species); absence of the A stripe (a less distinct, relatively wide stripe is present in some species, e.g., D. acrostomus, D. annandalei, D. xyrops); a short, wide premaxillary process (cleft in the upper jaw) with a tiny apophysis (bony tubercule) touching the kinethmoid bone; infraorbital 5 not or slightly reduced.
Older, molecular, phylogenies tended to agree that the latter represented a monophyletic group consisting of two major clades; the ‘Danio devario‘ group containing the larger, deeper-bodied species and the ‘D. rerio‘ clade comprising the smaller, slimmer fish. The currently invalid genus name ‘Brachydanio‘ was often adopted for members of the latter group and is seen in much of the older aquarium literature.
However in 2003 Fang Fang conducted a more detailed study based on morphological characters which included members of other related genera, and the results suggested for the first time that the genus Danio as previously considered represents a polyphyletic grouping, i.e., not all members derived from a single common ancestor.
These results have largely been supported by subsequent phylogenetic analyses (e.g. Mayden et al., 2007), although Devario has still undergone a little reshuffling, particularly following Fang et al. (2009).
In that study the two species previously comprising the genus Inlecypris were brought into synonymy with Devario and three species formerly included in Microrasbora were moved into the new genus Microdevario based on possession of shared synapomorphies with Devario.
The existence of a monophyletic clade consisting of the genera Devario, Chela, Laubuca, Microdevario and Microrasbora was also hypothesised, a theory upheld in the more recent study by Tang et al. (2010). The genus Betadevario (Pramod et al., 2010) is also nested within this grouping and is sister to Devario and Microrasbora.
Within the family Cyprinidae the ‘Devario clade’ is most closely-related to a ‘Danio clade’ containing the genera Danio and Danionella plus an ‘Esomus clade’ which groups Esomus alongside Paedocypris and Sundadanio. Closer relationships within Devario itself require further research, however.
- Fang, F., 2003 - Copeia 2003(4): 714-728
Phylogenetic Analysis of the Asian Cyprinid Genus Danio (Teleostei, Cyprinidae).
- Fang, F., M. Norén, T. Y. Liao, M. Källersjö and S. O. Kullander, 2009 - Zoologica Scripta 38(1): 1-20
Molecular phylogenetic interrelationships of the south Asian cyprinid genera Danio, Devario and Microrasbora (Teleostei, Cyprinidae, Danioninae).
- Mayden, R. L., K. L. Tang, K. W. Conway, J. Freyhof, S. Chamberlain, M. Haskins, L. Schneider, M. Sudkamp, R. M. Wood, M. Agnew, A. Bufalino, Z. Sulaiman, M. Miya, K. Saitoh, S. He, 2007 - Journal of Experimental Zoology, Molecular Development and Evolution 308B: 642-654
Phylogenetic relationships of Danio within the order Cypriniformes: a framework for comparative and evolutionary studies of a model species.
- Pramod, P. K., F. Fang, K. Rema Devi, T.-Y. Liao, T. J. Indra, K. S. Jameela Beevi and S. O. Kullander, 2010 - Zootaxa 2519: 31-47
Betadevario ramachandrani a new danionine genus and species from the Western Ghats of India (Teleostei: Cyprinidae: Danioninae).
- Roberts, T. R., 2007 - Raffles Bulletin of Zoology 55(1): 131-140
The 'Celestial Pearl Danio', a new genus and species of colourful minute cyprinid fish from Myanmar (Pisces: Cypriniformes).
- Tang, K. L., M. K. Agnew, W. J. Chen., M. V. Hirt, T. Sado, L. M. Schneider, J. Freyhof, Z. Sulaiman, E. Swartz, C. Vidthayanon, M. Miya, K. Saitoh, A. M. Simons, R. M. Wood and R. L. Mayden, 2010 - Molecular Phylogenetics and Evolution 57(1): 189-214
Systematics of the subfamily Danioninae (Teleostei: Cypriniformes: Cyprinidae).