Danio

Lot 6: Identification tips for Danio rerio

Sort out small-sized fish with metallic blue lateral bands on the sides as well as on caudal and anal fins:

…….. place them labeled as Danio sp.

The fish specimens of this ‘Lot’ are small-sized (2.6 – 4.4 cm) are one of the most beautifully ornamented individuals with metallic blue lateral bands on the sides as well as on caudal and anal fins, found frequenting along the margins of clear (uncontaminated), shallow and weedy streams (Song, Suswa in the Eastern Doon) and Asan, Tons in the Western Doon).

Unhesitatingly, keep it identified as: ……….. Danio rerio

Other characterizations of this species include the presence of 2 pairs of barbels, the rostrals being shorter but the maxillary ones extending beyond eye orbit. Body is laterally compressed with narrow, upwardly directed cleft of mouth.

Colouration is most attractive with greenish-silvery on the dorsum and flanks, paler along the abdomen; 5 metallic blue bands on the sides demarcated by 4 silvery ones (2 mid-lateral, 1 ventro-lateral and 1 dorso-lateral; extending up to the caudal fin, 2 each above and below the fork point; a 5th whitish line is exclusively on both the caudal lobes); 4 bluish lines run across the anal fin (3 on the main fin and 1 along the base).

Curiously enough, whether dwelling in the streams of Doon Valley (Uttarakhand) or Banda district (at River Paisuni or Mandakini Ganga at Chitrakoot, Uttar Pradesh, India), on most occasions Danio rerio is found living with the shoals of Devario devario (Lot 7). Further, the occurrence of Esomus danricus and Rasbora daniconius (both of Lot 5) is not uncommon with the shoals of Danio rerio.

Danio rerio: Lateral view showing broader metallic blue bands on the flank separated by narrower slivery white bands.  

 

MORE PHOTOGRAPHS OF Danio rerio

Danio rerio (Middle part of body enlarged): Mark the presence of 5 metallic blue bands on the sides demarcated by 4 silvery ones (2 mid-lateral, 1 ventro-lateral and 1 dorso-lateral) ; extending up to the caudal fin, 2 each above and below the fork point; a 5th whitish line is exclusively on both the caudal lobes)
Danio rerio (Middle part of body enlarged): Mark the presence of 5 metallic blue bands on the sides demarcated by 4 silvery ones (2 mid-lateral, 1 ventro-lateral and 1 dorso-lateral) ; extending up to the caudal fin, 2 each above and below the fork point; a 5th whitish line is exclusively on both the caudal lobes)
Danio rerio (Caudal fin enlarged): 4 narrower, silvery lines (2 mid-lateral, 1 ventro-lateral and 1 dorso-lateral) extending up to the caudal fin, 2 each above and below the fork point; a 5th whitish line is exclusively on both the caudal lobes.
Danio rerio (Caudal fin enlarged): 4 narrower, silvery lines (2 mid-lateral, 1 ventro-lateral and 1 dorso-lateral) extending up to the caudal fin, 2 each above and below the fork point; a 5th whitish line is exclusively on both the caudal lobes.
Danio rerio (Anal fin enlarged): 4 bluish lines run across the anal fin (3 on the main fin and the 4th one along the base).
Danio rerio (Anal fin enlarged): 4 bluish lines run across the anal fin (3 on the main fin and the 4th one along the base).
Danio rerio (Head enlarged, lateral view): 2 pairs of barbels, the rostrals (r.b.) being shorter but the maxillary ones (max. b.) extending beyond eye orbit.
Danio rerio (Head enlarged, lateral view): 2 pairs of barbels, the rostrals (r.b.) being shorter but the maxillary ones (max. b.) extending beyond eye orbit.
Danio rerio (Head enlarged, latero-frontal view): 2 pairs of barbels, the rostrals (r.b.) being shorter but the maxillary ones (max. b.) extending beyond eye orbit. Shallow cleft of mouth, directed obliquely upwards.
Danio rerio (Head enlarged, latero-frontal view): 2 pairs of barbels, the rostrals (r.b.) being shorter but the maxillary ones (max. b.) extending beyond eye orbit. Shallow cleft of mouth, directed obliquely upwards.

FAVOURITE DWELLING SITES OF Danio rerio

Suswa River (Eastern Doon): At Raiwala, the weedy (Veronica sp.), swampy stretch harbouring Danio rerio, Devario devario, Colisa, Puntius, Channa sp., Cobitids etc.
Suswa River (Eastern Doon): At Raiwala, the weedy (Veronica sp.), swampy stretch harbouring Danio rerio, Devario devario, Colisa, Puntius, Channa sp., Cobitids etc.
Suswa river (Eastern Doon): Flowing through Raja ji National Park. A favourite dwelling ground of fishes like Esomus, Rasbora, Danio, Devario, Barilius, Puntius amongst the smaller ones and Tor, Labeo, Chagunius sp. etc.amongst the larger ones in deeper zones.
Suswa river (Eastern Doon): Flowing through Raja ji National Park. A favourite dwelling ground of fishes like Esomus, Rasbora, Danio, Devario, Barilius, Puntius amongst the smaller ones and Tor, Labeo, Chagunius sp. etc.amongst the larger ones in deeper zones.
Song River (Eastern Doon): Gently flowing stretch at Golatappar forest tract, a favourite dwelling site for Danio, Devario, Puntius, Barilius sp. etc.
Song River (Eastern Doon): Gently flowing stretch at Golatappar forest tract, a favourite dwelling site for Danio, Devario, Puntius, Barilius sp. etc.
Asan River (Western Doon): Isolated gently flowing weedy channels at Herbertpur, a favourite dwelling ground of smaller species like Esomus, Rasbora, Puntius, Danio, Devario, Barilius sp. etc.
Asan River (Western Doon): Isolated gently flowing weedy channels at Herbertpur, a favourite dwelling ground of smaller species like Esomus, Rasbora, Puntius, Danio, Devario, Barilius sp. etc.
  • Systematic position:
    Family: Cyprinidae

Subfamily: Rasborinae (= Danioninae)

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