New Species of Rhabdosynochus Mizelle and Blatz 1941 (Monogenoidea: Diplectanidae) From the Gills of the Cultured Centropomus viridis (Perciformes) in the Mexican Eastern Tropical Pacific



There are currently nine monogenoidean species of Rhabdosynochus infecting the gill lamellae of wild and cultured centropomid fishes from tropical and subtropical waters of the western Atlantic and eastern Pacific Oceans. The purpose of the present study was to describe the morphological distinctiveness of two new species of Rhabdosynochus found on the cultured Centropomus viridis collected from floating cages from the Mexican eastern Tropical Pacific in 2018.


monogenoideans were fixed with 4–5% formalin solution, observed and measured as temporary or permanent mounts stained with Gomori’s trichrome, and mounted in Canada balsam. Other specimens were mounted on slides using a mixture of lactic acid (LA) and glycerin-ammonium picrate (GAP) and then remounted in Canada balsam to obtain measurements of the haptoral structures and copulatory complex. Illustrations were prepared with the aid of a drawing tube using a Leica microscope DM 2500 with Nomarski interference contrast.


Rhabdosynochus viridisi n. sp. is mainly differentiated from all other congeneric species in the shape and size of their copulatory complexes, i.e., length 75–105 µm vs. 45–55 µm in R. alterinstitus, 26–44 µm in R. volucris, 19–22 µm in R. lituparvus, 21–37 µm in R. siliquaus, 48–75 µm in R. hargisi, 37–44 µm in R. hudsoni and 44–61 µm in R. guanduensis. Rhabdosynochus pacificus n. sp. differs from all other species of the genus in having an accessory piece (one subunit) distally twisted.


Based on the morphometric differences of the two new species described above, the number of valid species of Rhabdosynochus has now increased to 11. These two new species of Rhabdosynochus represent the first described species of the genus on C. viridis.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2


  1. 1.

    Kritsky DC, Boeger WA, Robaldo RB (2001) Neotropical Monogenoidea. 38. Revision of Rhabdosynochus Mizelle and Blatz, 1941 (Polyonchoinea: Dactylogyridea: Diplectanidae), with descriptions of two new species from Brazil. Comp Parasitol 68(1):66–75

    Google Scholar 

  2. 2.

    Kritsky DC, Bakenhaster MD, Fajer-Ávila EJ, Bullard SA (2010) Rhabdosynochus spp. (Monogenoidea: Diplectanidae) infecting the gill lamellae of snooks, Centropomus spp. (Perciformes: Centropomidae), in Florida, and redescription of the type species R. Rhabdosynochus. J Parasitol 96:879–886.

    Article  PubMed  Google Scholar 

  3. 3.

    Doro AV, Kozlowiski de Azebedo R, Luque JLF (2012) Three new species of Monogenea (Platyhelminthes) parasites of fish in the Guandu river, southeastern Brazil. Acta Sci Biol Sci 34(4):483–490.

    Article  Google Scholar 

  4. 4.

    Domingues MV, Boeger WA (2008) Phylogeny and revision of Diplectanidae Monticelli, 1903 (Platyhelminthes: Monogenoidea). Zootaxa 1698:1–40.

    Article  Google Scholar 

  5. 5.

    Mendoza-Franco EF, Violante-González J, Vidal-Martínez VM (2006) A new diplectanid (Monogenea) genus and species from the gills of the black snook Centropomus nigrescens (Perciformes, Centropomidae) of the Pacific coast of Mexico. J Parasitol 92(3):481–485.

    Article  PubMed  Google Scholar 

  6. 6.

    Mendoza-Franco EF, Violante-González J, Vidal-Martínez VM (2008) New species of Rhabdosynochus Mizelle and Blatz 1941, (Monogenoidea: Diplectanidae) from the gills of centropomid fishes (Teleostei) off the Pacific coast of Mexico. J Parasitol 94(1):28–35.

    Article  PubMed  Google Scholar 

  7. 7.

    Bush AO, Lafferty KD, Lotz JM, Shostak AW (1997) Parasitology meets ecology on its own terms: Margolis et al. revisited. J. Parasitol 83:575–583.

    CAS  Article  PubMed  Google Scholar 

  8. 8.

    Tringali MD, Berts TM, Seyoum S, Bermingham E, Bartolacci D (1999) Molecular phylogenetics and ecological diversification of the Transisthmian fish Centropomus (Perciformes: Centropomidae). Mol Phylogenet Evol 13(1):193–207.

    CAS  Article  PubMed  Google Scholar 

  9. 9.

    Escárcega Rodríguez S (2005). El robalo: avances biotecnológicos para su crianza. Mexico. AGT Editor S.A. 126 p

  10. 10.

    Ibarra-Castro L, Navarro-Flores J, Sánchez-Téllez JL, Martínez-Brown JM, Ochoa-Bojórquez LA, Rojo-Cebreros AH (2017) Hatchery production of Pacific white snook at CIAD-Unity Mazatlán, Mazatlán, Mexico. World Aquacult 48:25–29

    Google Scholar 

  11. 11.

    Morales-Serna FN, López-Moreno DG, Medina-Guerrero RM, Abad-Rosales SM, Martínez-Brown JM, Ibarra-Castro L, Fajer-Avila EJ (2020) Toxicity of formalin for juvenile Centropomus viridis and in vitro efficacy against the parasite Rhabdosynochus sp (Monogenea: Diplectanidae). J Appl Ichthyol 36(5):740–744.

    CAS  Article  Google Scholar 

  12. 12.

    Suárez-Morales E, Ho JS, Santana-Piñeros AM (2008) Caligus tenuifurcatus Wilson, 1937 (Copepoda, Siphonostomatoida), a parasite of centropomid and lutjanid teleosts from a coastal system of the Mexican Pacific. Acta Parasitol 53(4):397–403.

    Article  Google Scholar 

  13. 13.

    Soto-Rodríguez SA, Lozano-Olvera R, Abad-Rosales SM, Martínez-Brown JM, Ibarra CL (2019) Susceptibility of Pacific white snook Centropomus viridis to Vibrio species. Dis Aquat Organ 134(3):189–195

    Article  Google Scholar 

  14. 14.

    García-Vásquez A, Hansen H, Christison KW, Rubio-Godoy M, Bron JE, Shinn AP (2010) Gyrodactylids (Gyrodactylidae, Monogenea) infecting Oreochromis niloticus niloticus (L.) and O. mossambicus (Peters) (Cichlidae): a pan-global survey. Acta Parasitol 55(3):215–229.

    Article  Google Scholar 

Download references


This study was supported by the following agencies: Instituto Nacional de Pesca y Acuacultura (INAPESCA) through the Direccion General Adjunta de Investigacion en Acuacultura (DGAIA) and the Centro Regional de Investigación Acuícola y Pesquera (CRIAP) located in Manzanillo, Colima, Mexico. Fish specimens were kindly provided by Alejandro P. Muñoz (CRIAP). Alma S. Sandoval and Yuliana A. Zurita Moo assisted us during laboratory work. MMR was supported by a Master student fellowship (scholarship number 708028) from the Consejo Nacional de Ciencia y Tecnología (CONACyT), Mexico. This paper derives partially from the master thesis of MMR (Universidad Autónoma Metropolitana Unidad-Xochimilco, Mexico city).

Author information



Corresponding author

Correspondence to Edgar F. Mendoza-Franco.

Ethics declarations

Conflict of Interest

The authors declare that they have no conflict of interest.

Ethical Approval

All applicable institutional, national and international guidelines for the care and use of animals were followed.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Montero-Rodríguez, M., Mendoza-Franco, E.F. & Téllez, N.A.L. New Species of Rhabdosynochus Mizelle and Blatz 1941 (Monogenoidea: Diplectanidae) From the Gills of the Cultured Centropomus viridis (Perciformes) in the Mexican Eastern Tropical Pacific. Acta Parasit. (2020).

Download citation


  • Monogenoidea
  • Centropomidae
  • Cultured fish
  • Floating cages
  • Ectoparasitic platyhelminths
  • Commercial marine fish