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:

  • teeth with one cusp present throughout ontogeny;
  • one row of teeth present on premaxilla;
  • replacement tooth trench or crypt in dentary absent;
  • third postcleithrum absent.
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    Synonyms

    Clupeopetersius Pellegrin, 1928

     

    Type species

    Clupeocharax schoutedeni Pellegrin, 1926 by monotypy.

     

    Currently, this genus is monospecific.

     

    Bibliography

  • Pellegrin J., 1926. Les Characinidés du Congo. Comptes rendus de l’Association française pour l’Avancement des Sciences, Congrès de Grenoble: 420-421.
  • Pellegrin J., 1928b. Mutanda ichthyologica: Clupeocharax Pellegrin. Revue de Zoologie et de Botanique africaines, 16, 1: 82.
  • Poll M., 1967a. Révision des Characidae nains africains. Annales du Musée royal de l’Afrique centrale, série in-8°, Sciences Zoologiques, 162 p.
  • Zanata A.M. & Vari R.P., 2005. The family Alestidae (Ostariophysi, Characiformes); a phylogenetic analysis of a trans-Atlantic clade. Zoological Journal of the Linnean Society, 145: 1-144.
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    Clupeocharax schoutedeni Pellegrin, 1926

    clupeocharax_schoutedeni_picture

    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.

    mouth_cschoutedeni

    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).

     

    IUCN assessment

    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.

     

    FishBase link

     

    Bibliography

  • Monsembula Iyaba R.J.C. & Stiassny M.L.J., 2013. Fishes of the Salonga National Park (Congo basin, central Africa): a list of species collected in the Luilaka, Salonga, and Yenge Rivers (Equateur Province, Democratic Republic of Congo). Check List, 9, 2:246-256.
  • Pellegrin J., 1926a. Les Characinidés du Congo. Comptee rendus de l’Association française pour l’Avancement des Sciences, Congrès de Grenoble: 420-421.
  • Pellegrin J., 1928b. Mutanda ichthyologica: Clupeocharax Pellegrin. Revue de Zoologie et de Botanique africaines, 16, 1: 82.
  • Poll M., 1967a. Révision des Characidae nains africains. Annales du Musée royal de l’Afrique centrale, série in-8°, Sciences Zoologiques, 162 p.