Marine Biology

, Volume 56, Issue 4, pp 311–317 | Cite as

Diagnostic value of the thelycum in euphausiids. II. Oceanic species, genus Nematoscelis

  • G. Costanzo
  • L. Guglielmo


The thelycum morphology of 7 species of the genus Nematoscelis, based upon observations with the scanning electron microscope, is described. The thelycum of N. megalops and N. difficilis did not differ either with respect to general morphology of the thelycum, or in spermatophore insertion. In the other 5 species, N. tenella, N. gracilis, N. atlantica, N. lobata, N. microps, the main thelycum structure consists of a central lobe of various forms, to which a filamentous spermatic mass is attached. Preliminary observations on the position of the genital pores of two species are reported briefly.


Electron Microscope Scanning Electron Microscope Preliminary Observation General Morphology Central Lobe 
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Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • G. Costanzo
    • 1
  • L. Guglielmo
    • 1
  1. 1.Istituto di IdrobiologiaUniversità di MessinaMessinaItaly

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