Clupeocharax
Clupeocharax Pellegrin, 1926
A distinctive feature of Clupeocharax is that it has on each jaw a single row of numerous small cone-shaped teeth leaning backwards. Among the Petersiini, the genera Clupeocharax and Lepidarchus are the alone to have unicuspid teeth. Furthermore, Clupeocharax has a very short lateral line, with 5-6 pored scales (while the complete longitudinal line has 30-32 scales). Although the majority of alestids or Petersiini have tri- to multicuspidate dentition as adults, three genera in the family, Hydrocynus, Clupeocharax and Lepidarchus, have unicuspid dentition (Zanata & Vari, 2005).
A phylogenetic analysis based on 200 osteological characters shown that Clupeocharax belongs to the same monophyletic clade than Ladigesia, Lepidarchus and Tricuspidalestes (Zanata & Vari, 2005). Within this clade Clupeocharax is the sister taxon to the clade consisting to the three other gehera. Clupeocharax is characterised by four autapomorphies which characterise this single genus:
Synonyms
Clupeopetersius Pellegrin, 1928
Type species
Clupeocharax schoutedeni Pellegrin, 1926 by monotypy.
Currently, this genus is monospecific.
Bibliography
Clupeocharax schoutedeni Pellegrin, 1926
Type and type locality
Clupeocharax schoutedeni Pellegrin, 1926: 159-160. Type locality: “Tondu”. Holotype: MRAC 19699
Synonyms
Clupeocharax schoutedeni Pellegrin, 1926
Clupeopetersius schoutedeni Pellegrin, 1928
Common names
Estonian: Heeringtetra
Description
Diagnosis: body depth 3.9-4 (4) and head length 3.5-3.7 (3.4) in standard length. Very prominent lower jaw. Parietal fontanel present. Dental formula: [16-20 (upper jaw), 20-24 (lower jaw)] [(+/-30) (upper jaw), (+/-30) (lower jaw)] (see figure below); a single row with many small teeth. Cuspids number: 1 (unicuspidate). Unpaired fins non-filamentous. Dorsal fin: II,8 (II,8). Anal fin: III,17-19 (III,17). Gill rakers on the lower limb of the first gill arch: 19-21 (20). Longitudinal line scales: 29-30+1-2 (32); transversal line scales: 5½ (above lateral line)/3½-4½ (below lateral line) (5½/4½); scales around caudal peduncle: 10. Incomplete lateral line: 5-6 (5) tubes.
Clupeocharax schoutedeni: mouth open in lingual view.
Maximum reported size: 47 mm SL.
Colour: a thin longitudinal blackish line. Fins are hyalin.
Distribution
Lake Tumba, Lake Yandja (near Yangambi) and the Salonga River (Ruki drainage), in the middle Congo River basin in Democratic Republic of the Congo. Recent collections in and around Lake Mai-Ndombe have shown the species to occur there. It is probable that the species is more widespread in Central Congo (see also Faunafri).
All bigger fish in Lake Tumba seem to be disappeared by overfishing. The number of mature individuals has declined. Both the EOO and AOO qualify this species for the Vulnerable status.
Major threats: in Lake Tumba, the mean mesh size of the nets used in this lake are around 1 cm, causing threats by overfishing. All bigger fish in Lake Tumba seem to be disappeared. Lake Tumba does not produce fish any more. All the fishermen seem to have turned to agriculture.
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