THE NOTHOBRANCHIUS SITE

MRAC 73-25-P-1108; holotype, male, 30.5 mm SL; DR Congo: Katanga province: Malinde River drainage, approx. 12°56' S, 29°22' E; collected by J. J. Symoens, 23 Apr 1962.

MRAC 73-25-P-1109 (1)

Nothobranchius symoensi is distinguished from all other species of the genus by a male colour pattern characterized by: an irregular red-orange and blue reticulation pattern on the sides; head and anterior part of body orange-red; branchiostegal membrane orange; unpaired fins with narrow dark subdistal band and distinct light blue distal margin.

Subgenus: Zononothobranchius

Species group: N. brieni group

Nothobranchius symoensi was established as a species by Wildekamp in 1978, and that status has since been accepted by all authors.

DR Congo: Katanga province: Malinde River drainage, approx. 12°56' S, 29°22' E.

This species is endemic to seasonal freshwater habitats in northern Zambia and south-eastern Democratic Republic of Congo. It is known from thickly vegetated temporary pools and swamps, and flooded grassy areas adjacent to slow-flowing seasonal rivers in the upper Luapula drainage in northern Zambia and south-eastern Democratic Republic of Congo.

Bangweulu–Mweru (544)

1171–1225 m

Personal observation at collecting sites (5 locations):

Water temperature: 22.6–27.2 °C

pH: 6.2–6.8

TDS:  5–20 ppm

Conductivity: 10–40 µS

None

This species has an annual life cycle.

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

Maximum size reported: 39.3 mm SL (MRAC B4-008-P-0013, male)

Diploid chromosome number 2n = 36, NF = 68, karyotype structure 20m+12sm+4st/a (Krysanov & Demidova, 2018).

Karyotype structure unique in the genus.

The specific name is given in honor of Prof. Jean-Jacques Symoens, Belgian botanist and ecologist from the University of Lubumbashi, DR Congo, discoverer of the species.

Endangered B1ab(iii)+2ab(iii) (Nagy & Watters, 2019);

Previous assessments: Endangered B1ab(iii)+2ab(iii) (Moelants, 2010);

Least Concern (2009)

    Wildekamp, R. H. 1978. Redescription of Nothobranchius brieni Poll, 1938 and the description of three new Nothobranchius species (Pisces, Cyprinodontidae) from the province of Shaba, Zaire. Revue de Zoologie Africaine, 92 (2): 341–354. [taxonomy as Nothobranchius symoensi]

    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 symoensi. The IUCN Red List of Threatened Species: e.T169416A58320025. [conservation]