The fish diversity of the Kundelungu National Park (KNP), one of the seven national parks of the Democratic Republic of the Congo, has never been thoroughly studied. This first checklist is presented based on a literature compilation and the study of historical (1939–1969) and recent collections (2012–2017). A total of 96 taxa are reported, including 64 native described species, one introduced species (Poecilia reticulata), 13 new species that await formal description and 18 possibly new species that require further investigation to verify their status. These taxa represent 39 genera and 17 families from the KNP including its Buffer Zone (BZ). Only six taxa, including five endemics, are known from the Core Zone on the Kundelungu Plateau (1300–1700 m alt.). At lower altitudes (800–1100 m), in the Annex Zone, 71 taxa, including 17 endemics, were found. Finally, 50 taxa, including 13 endemics and one introduced species, are known from its BZ. The fish fauna of the KNP is threatened by overfishing, destructive fishing practices, and habitat degradation due to mining pollution, and deforestation for agriculture on the river banks. The present study provides the much needed baseline data for the protection and conservation planning of this fish fauna, for which conservation suggestions are formulated.

Two new Kneria species, K. luansaensis sp. nov. and K. maxi sp. nov., are described from the Luansa River, a left bank tributary of the lower Luapula in the Bangweulu–Mweru ecoregion, based on an integrative approach using morphological and COI barcoding evidence. While K. luansaensis sp. nov. occurs from the source of the Luansa further downstream to above the last of the three Sanshifolo Falls, K. maxi sp. nov. only occurs downstream of all these three major falls. In Kneria, males of about ≥ 33 mm L_S have an opercular and a postopercular organ. The number of lamellae on the latter seems to contain some alpha-taxonomic information, although this requires further study as allometric changes occur at about ≤ 45 mm L_S. Additional external morphological characters differ between sexes, i.e., the (i) pectoral fin width (wider in males than females), (ii) dorsal fin height (longer in males than females), and (iii) length of the longest ray of the lower caudal fin lobe (longer in males than females). Agriculture, fishing with ichthyotoxines, and logging are the most pressing threats on the Luansa and thus to both the new species. Their discovery in one of the rivers of the Kundelungu Plateau and its surroundings located outside the present-day boundaries of the Kundelungu National Park highlights the need for a refined and improved protection strategy for this freshwater key biodiversity area.

An annotated checklist of the ichthyofauna of the Upemba National Park, draining part of the Upper Lualaba basin and situated in the southern part of the Democratic Republic of the Congo, is presented, based on a literature review, a re-examination of museum collections, and a study of recent collections (2012–2020). In total, 247 native and 1 introduced species, Heterotis niloticus, are reported. The native species belong to 78 genera, 26 families, and 15 orders. Of these, 45 species (18%) are endemic to the park, 35 species (14%) await formal description, and 5 taxa (2%) need further study to clarify their status. With 51 species, the Cyprinidae is by far the most species-rich family, followed by the Mormyridae (26), Mochokidae (26), Alestidae (18), Distichodontidae (18), Amphiliidae (17), and Cichlidae (16). The remaining families are represented by less than 15 species. Comments about the species distribution and the fish fauna shared with adjacent ecoregions are provided. Although the park provides some protection for the fish species living within its borders by limiting human access to the core zone, the annex and buffer zones are both subject to strong anthropogenic pressure. These observations underscore the need for the implementation and further elaboration of fish-related preservation guidelines and plans to enable better protection/conservation of the park’s ichthyofauna.