THE NOTHOBRANCHIUS SITE

BE_RMCA_VERT.2025.008.P.0021, male, 36.3 mm SL; DR Congo: Lake Mweru basin: Lufukwe system: ephemeral pool in the floodplain of the seasonal river, 1.5 km west of Mukobe village, 09°41'32.9" S, 28°12'42.5" E, 962 m alt.; B. Nagy, A. Chocha Manda & A. Kalumba, 12 Apr 2023 [field code: CD 23-9].

BE_RMCA_VERT.2025.008.P.0022–0027 (6), BE_RMCA_VERT.2025.008.P.0028–0030 (3).

Nothobranchius marmoreus is distinguished from all other species of the genus by the unique combination in male colouration of having a body with irregular red-brown patches and stripes, forming a marble-like mottled pattern; and anal and caudal fins with slender yellow to amber subdistal band and broad dark brown distal band.

Subgenus: Zononothobranchius

Species group: N. brieni group

Nothobranchius marmoreus was established as a species by Nagy in 2025.

DR Congo: Lake Mweru basin: Lufukwe system: ephemeral pool in the floodplain of the seasonal river, 1.5 km west of Mukobe village, 09°41'32.9" S, 28°12'42.5" E, 962 m alt.

This species is endemic to seasonal freshwater habitats of the upper Congo drainage in south-eastern DR Congo. It is currently known only from the type locality, a remnant pool associated with the Lufukwe system in the Lake Mweru basin. The Lufukwe is an affluent entering the lake from a south-western direction.

Bangweulu–Mweru (544)

962 m

The habitat was 25–30 m in diameter, about 1.5 m deep at its deepest point. Shallower parts and edges of the pool were overgrown by grass. The water was turbid. The water temperature late morning was 24.0 °C, the pH was 7.4, and it contained 35 ppm of total dissolved solids. Water parameters, measured at the same location during the previous visit of 10 April 2016, showed the following values of: temperature of 27.8 °C in mid-afternoon; pH of 7.36; total dissolved solids of 42 ppm. 

None

The species has an annual life cycle.

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

Maximum size reported: 41.2 mm SL (BBE_RMCA_VERT.2025.008.P.0022–0027, paratype, male)

Not known

The specific epithet marmoreus is a Latin adjective deriving from the ancient Greek word marmaros (μάρμαρος) in the meaning of resembling marble, marblelike, and in reference to the irregularly mottled marbled colour pattern on the body of the males.

Not evaluated

Recommended as Endangered in Nagy, 2025.

​     Nagy, B. 2024. Off the (badly) beaten tracks. Practical Fishkeeping, 2024: 68–76. [collecting as Nothobranchius sp. Mukobe]

    Nagy, B. 2025. Review of cyprinodontiform fishes in the upper Congo drainage with descriptions of four new species of seasonal Nothobranchius (Nothobranchiidae) and a new species of ‘Lacustricola’ Lampeye (Procatopodidae) in South-Eastern DR Congo. Ecology and Diversity, 2 (2), 10006. [taxonomy as Nothobranchius marmoreus, distribution, ecology]