THE NOTHOBRANCHIUS SITE

BMNH 1983.4.7.3. holotpe, male, 45.0 mm SL; Sudan: Kordofan province, Jebel Megeinis, hafir No. 2, approx. 11°56' N, 32°06.2' E; collected by P. Howell, Jan 1950.

BMNH 1983.4.7.4-7 (4), BMNH 1983.4.7.8 (1), BMNH 1983.4.7.9-12 (4), BMNH 1983.4.7.13-14 (2), BMNH 1983.4.7.15 (1), BMNH 1983.4.7.16 (1),
BMNH 1983.4.7.17 (1), BMNH 1983.4.7.18 (1), BMNH 1983.4.7.19-20 (2), BMNH 1983.4.7.21-25 (5), BMNH 1983.4.7.26-49 (24)

Nothobranchius virgatus is distinguished from all other species of the genus by the male colour pattern of 10 to 12 distinct dark red-brown oblique bars on the sides; red-brown curved lines on dorsal and anal fin; and caudal fin plain blue with black vertical border; females with narrow faint grey oblique bars on sides.

Nothobranchius virgatus was established as a species by Chambers in 1984, and that status has since been accepted by all authors.

Costa (2018) assigned the species to the newly created subgenus Plesiobranchius.

Subgenus: Plesiobranchius

Sudan: Kordofan province, Jebel Megeinis, hafir No. 2, approx. 11°56' N, 32°06.2' E

This species is endemic to seasonal freshwater habitats in southern Sudan, South Sudan and western Ethiopia. It is known from ephemeral pools, swamps, temporary riverbeds and water reservoirs in the middle and upper Nile drainages. It has a disjunct distribution. In southern Sudan, several localities are known from around the foothills of the Nuba Mountains.

Upper Nile (522)

434–486 m

Personal observation at 6 collecting sites:

Water temperature: 22.8–32.1 °C

pH: 8.41–8.78

TDS:  53–90 ppm

Conductivity: 106–180 µS

N. nubaensis - 14%

N. rubroreticulatus - 3%

This species has an annual life cycle.

Embryonic development under captive conditions in peat moss is about five to eight months at room temperature.

Maximum size reported: 54.0 mm SL (BMNH 1983.4.7.13, male)

Diploid chromosome number 2n = 32, NF = 32, karyotype structure 32st/a (Krysanov & Demidova, 2018).

Fundamental number and karyotype structure unique in the genus.

The specific name is formed from virgatus (in Latin for striped) in reference to the oblique striped pattern on the sides.

Least Concern (Nagy & Watters, 2019);

Previous assessment: Data Deficient (Getahun, 2010)

    Sandon, H. 1950. A New Fish from the Sudan. Sudan Wild Life and Sport, 1 (3): 19–20.

    Sandon, H. 1950. An illustrated Guide to the Freshwater Fishes of the Sudan. Sudan Notes and Records, Khartoum. 61pp.

    Sandon, H. 1957. Problem Fish from Kordofan. Sudan Silva, 5 (1): 1–5.

    Chambers, J. 1984. A new Nothobranchius species (Teleosti, Cyprinodontiformes, Aplocheilidae) from the Sudan. Journal of Fish Biology, 25 (5): 505–513. [taxonomy as Nothobranchius virgatus]

    Nagy, B. 2011. Nothobranchius Explorations in the Nuba Mountains. Journal of the American Killifish Association, 44 (2): 37–57. [collecting, distribution]

    Nagy, B., F. P. D. Cotterill & D. U. Bellstedt. 2016. Nothobranchius sainthousei, a new species of annual killifish from the Luapula River drainage in northern Zambia (Teleostei: Cyprinodontiformes). Ichthyological Exploration of Freshwaters, 27 (3): 233–254. [phylogeny]

    Nagy, B. & B. R. Watters. 2019. Nothobranchius virgatus. The IUCN Red List of Threatened Species: e.T182266A58329749. [conservation]

    Nagy, B., B. R. Watters, P. D. W. van der Merwe, F. P. D. Cotterill & D. U. Bellstedt. 2020. Review of the Nothobranchius ugandensis species group from the inland plateau of eastern Africa with descriptions of six new species (Teleostei: Nothobranchiidae). Ichthyological Exploration of Freshwaters, 30 (1): 21–73. [phylogeny]