A morphological description of the sagittal otoliths of two mormyrids, Marcusenius macrolepidotus and Petrocephalus catostoma (Family: Mormyridae)

  • N.N. Nicolaai
  • A Jooste
Keywords: morphology, sagittal otoliths, SEM, freshwater fish identification

Abstract

The morphology of the sagittal otoliths of two South African mormyrid fish, Marcusenius macrolepidotus and Petrocephalus catostoma, were studied to determine possible morphological significance. The sagittae of M. macrolepidotus and P. catostoma are kidney-shaped and oblong, respectively. The ventral margin is slightly indented in the former and slightly flattened in the latter. The sulcus acusticus of both species is archaesulcoid but mesial in M. macrolepidotus and ostio-caudal in P. catostoma. The crista inferior in M. macrolepidotus is ridge-like and well defined posteriorly and anteriorly, whereas in P. catostoma it is clearly defined posteriorly and disappears anteriorly. The otoliths of both species do not have a rostrum, antirostrum or an excisura. The differences in sagittal morphology between the two mormyrid species are distinct.

Keywords: morphology, sagittal otoliths, SEM, freshwater fish identification

Published
2017-03-15
Section
Articles

Journal Identifiers


eISSN: 2224-073X
print ISSN: 1562-7020