THE NOTHOBRANCHIUS SITE

Key to the species of Nothobranchius brieni species group

 

Species of the genus Nothobranchius exhibit pronounced sexual dichromatism and dimorphism. Colour pattern elements and morphometric characters are based on mature males.

 

1a – Anal and caudal fins without distinct dark distal band.

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1b – Anal or caudal fins, or both, with distinct dark distal band.

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2a – Anal and caudal fins with light blue distal band.

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2b – Anal fin with orange-brown or yellow distal band; caudal fin with light blue band.

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3a – Dorsal fin with distinct light blue distal band; caudal fin with slender red-brown subdistal band; head depth 74-78 % HL; caudal peduncle length 1.5-1.6 times its depth (upper Luapula drainage).

................................................... N. symoensi

3b – Dorsal fin without light blue distal band; caudal fin without subdistal band; head depth 87-93 % HL; caudal peduncle length 1.4 times its depth (middle Luapula drainage).

.............................................. N. chochamandai

4a – Anal fin with broad yellow distal band; dorsal fin completely spotted with red-brown dots; caudal fin orange or spotted with red-brown dots and with a slender light blue distal band (Luangwa drainage).

....................................................... N. boklundi

4b – Anal fin with broad orange-brown distal band; dorsal fin with orange-brown markings, with black markings between first and second and between second and third fin rays at anterior band; caudal fin orange-brown with narrow light blue distal band (upper and middle Luapula drainage).

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5a – Dorsal and anal fins with irregular orange-brown spots; head length 25-29 % SL; head width 71-79 % HL (middle Luapula drainage).

................................................... N. sainthousei

5b – Dorsal and anal fins with irregular orange-brown bars; head length 30-39 % SL; head width 53-60 % HL (upper and middle Luapula drainage).

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6a – Head depth 75-77 % HL; caudal peduncle length 1.2-1.3 times its depth (middle Luapula drainage).

.......................................................... N. cooperi

6b – Head depth 78-84 % HL; caudal peduncle length 1.6 times its depth (upper Luapula drainage).

................................................... N. rosenstocki

7a – Anal and caudal fins with cream to light blue subdistal band.

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7b – Anal and caudal fins with yellow to orange subdistal band or caudal fin without subdistal band.

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8a – Anal and caudal fins with broad red-brown distal band (Lake Mweru Wantipa basin).

.................................................. N. oestergaardi

8b – Anal and caudal fins with slender black distal band (Kafue and upper Zambezi drainages).

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9a – Trunk scales with orange-red band resulting in an evenly distributed bar pattern on trunk; head with orange-red colour (Kafue and upper Zambezi drainages).

...................................................... N. kafuensis

9b – Trunk scales without orange-red scale band, and with irregular bars on trunk; head without orange-red colour (upper Zambezi drainage).

.................................................. N. capriviensis

10a – Caudal fin with light blue distal band.

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10b – Caudal fin with dark red-brown, dark brown, dark grey or black distal band.

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11a – Anal fin with orange subdistal band; head width 56-62 % HL (lower Luapula drainage).

....................................................... N. malaissei

11b – Anal fin with yellow subdistal band; head width 68-76 % HL (middle Lualaba drainage).

............................................................ N. brieni

12a – Dorsal fin with distinct light blue distal band.

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12b – Dorsal fin without distinct light blue distal band.

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13a – Anal fin with median and distal portions yellow; prepelvic length 46-49 % SL; caudal peduncle length 1.3-1.4 times its depth (upper Lufira drainage).

.............................................................. N. polli

13b – Anal fin with broad orange-red subdistal band and slender dark grey distal band; prepelvic length 50-53 % SL; caudal peduncle length 1.5-1.6 times its depth (lower Lufira drainage).

........................................................ N. flagrans

14a – Caudal fin with broad irregular yellow-orange subdistal band; anal fin with yellow median band, orange subdistal band and with slender red-brown distal band; head width 50-59 % HL (lower Lufira drainage).

......................................................... N. hassoni

14b – Caudal fin with slender orange semicircle subdistal band; anal fin without yellow median band, and with orange subdistal band and broad red-brown or dark brown distal band; head width 60-72 % HL (Lake Mweru basin).

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15a – Caudal fin plain red with orange subdistal band and red-brown distal band; caudal peduncle length between 1.4-1.6 times its depth (Lake Mweru basin: Lushiba Marsh).

....................................................... N. milvertzi

15b – Caudal fin yellow to light blue, with red-brown spots proximally and medially, with orange subdistal band and dark brown distal band; caudal peduncle length between 1.3-1.4 times its depth (Lake Mweru basin: Katate system).

.............................................................. N. ditte