THE NOTHOBRANCHIUS SITE

MRAC 2008-05-P-1, holotype, male, 42.9 mm SL; Sudan: Angarko, 21 km south of Dilling and 100 km north of Kadugli, (11°53'05.23" N, 29°42'31.82" E); 5 Dec 2002, M. Bellemans, [field code: Angarko SUD 02-3].

BMNH 2008.4.2.11-12 (2); MNHN 2008-1140, 1141 & 1179 (3); MRAC 2008-05-P-2 (1) & P-3 to 4 (2); MSNG 54286 (1); SAIAB 80410 (1)

Nothobranchius nubaensis can be distinguished from all other species of the genus by the following combination of characters: 17-19 dorsal fin rays; 17-19 anal fin rays; 29-30 scales in median lateral series; dorsal and anal fin with short filamentous rays in males; pelvic fins short, tips reaching the anus; orange-red head with 3 distinct oblique bars on the operculum; dorsal fin light blue with a pattern of irregular orange-red spots and elongated yellow spots in distal areas; anal fin yellow, light blue at base, with a pattern of orange-red spots; pelvic fins yellow with a pattern of orange-red spots; pectoral fins orange-red with a light blue margin; caudal fin orange-red, with short pale or dark red lines extending from fin base onto fin rays (Valdesalici et al., 2009).

Subgenus: Zononothobranchius

Species group: N. ugandensis group

Nothobranchius nubaensis was provisionally described by Bellemans in 2003 but it was a nomenclaturally unavailable name for the reasons that it was mentioned to be a provisional description and no holotype has been designated. Subsequently, the species has been established by Valdesalici, Bellemans, Kardashev & Golubtsov in 2009, and that status has since been accepted by all authors.

Sudan: Angarko, 21 km south of Dilling and 100 km north of Kadugli, (11°53'05.23" N, 29°42'31.82" E).

This species is endemic to southern Sudan and western Ethiopia. It is known from temporary marshes, rainwater filled depressions and ephemeral pools formed in seasonal riverbeds in the Wadi Al Ghallah drainage in South Kordofan and in the Khor Abu Habl system in the White Nile drainage in West Kordofan around the foothills of the Nuba Mountains and in the Sobat system in the White Nile drainage in western Ethiopia.

Upper Nile (522)

442–701 m

Personal observation at collecting site:

Water temperature: 22.8 °C

pH: 8.73

TDS:  63 ppm

Conductivity: 126 µS

N. virgatus - 40%

This species has an annual life cycle.

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

Maximum size reported: 49.9 mm SL (ZMMGU P22009)

Diploid chromosome number 2n = 36 (Valdesalici, 2015), NF = 62, karyotype structure 14m+12sm+10st/a (Krysanov & Demidova, 2018).

Karyotype structure unique in the species group (Krysanov et al., 2023).

The specific name is given as a reference to the type locality, which lies in the Nuba mountains.

Vulnerable B2ab(iii) (Nagy & Watters, 2019)

​    Bellemans, M. 2003. A new Nothobranchius from the Sudan. A provisional description of Nothobranchius nubaensis n sp. BKA Separatum, unnumbered pages. [taxonomy as Nothobranchius nubaensis, name not available]

    Valdesalici, S., M. Bellemans, K. Kardashev & A. Golubtsov. 2009. Nothobranchius nubaensis (Cyprinodontiformes: Nothobranchiidae) a new annual killifish from Sudan and Ethiopia. Aqua International Journal of Ichthyology, 15 (3): 143–152. [taxonomy as Nothobranchius nubaensis]

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

    Nagy, B. & B. R. Watters. 2019. Nothobranchius nubaensis. The IUCN Red List of Threatened Species 2019: e.T53904366A58340374. [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, IEF-1129, pp. 1-53. [phylogeny]

    Krysanov, E. Y., B. Nagy, B. R. Watters, A. Sember & S. A. Simanovsky. 2023. Karyotype differentiation in the Nothobranchius ugandensis species group (Teleostei, Cyprinodontiformes), seasonal fishes from the east African inland plateau, in the context of phylogeny and biogeography. Comparative Cytogenetics, 17 (1): 13–29. [chromosomes]