The gelatinous matrix of the teleost Helicolenus dactylopterus dactylopterus (Delaroche, 1809) in the context of its reproductive strategy

Abstract

The bluemouth, Helicolenus dactylopterus dactylopterus (Pisces: Sebastidae), is a zygoparous species with internal fertilization that stores the spermatozoa in crypts within the female ovaries. It spawns gelatinous egg masses that were investigated in this study. Histological analysis confirmed that the ovarian wall and peduncular epithelia play an important role in the production of this gelatinous matrix that contained both oocytes and embryos. Cleavage and blastulae were the most frequent embryonic development stages observed and the tail bud was the latest stage reached. The chemical composition of the matrix was also investigated, revealing that water and proteins are the major components of this substance. This is the first study exclusively dedicated to the investigation of the composition, function and importance of the gelatinous matrix of H. d. dactylopterus in the context of its reproductive strategy.

Keywords:

• Egg masses
• gelatinous matrix
• Helicolenus
• Scorpaeniformes
• zygoparity

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Acknowledgements

We thank the Embryology group of the Departamento de Biologia Animal of the Faculdade de Ciências da Universidade de Lisboa for their support in the embryonic development and Prof. Eduardo Crespo and Prof. Rui Rebelo for their help in the identification of the structures involved in the production of the gelatinous matrix. We also thank Patrick Reis-Santos for revising the English, and two anonymous referees for their valued suggestions for improving the manuscript. V. Sequeira and P. Rifes were funded by grants from Fundação para a Ciência e Tecnologia, SFRH/BDD/22746/2005 and SFRH/BD/37423/2007, respectively. This research was also partially supported by contract CTM2006-13964-C03-01 of the ‘Ministerio de Educación y Cultura’, Spain.

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark