Two new species of Monstrilla (Copepoda: Monstrilloida: Monstrillidae) from a protected reef system of the Mexican Caribbean

  • Eduardo Suárez-Morales El Colegio de la Frontera Sur (ECOSUR) Unidad Chetumal, Quintana Roo, Mexico, 77014
Keywords: Caribbean reef systems, parasitic copepods, monstrilloids, taxonomy, reef crustaceans, SEM


Several adult female monstrilloid copepods, collected in March 2022 from the protected reef area of Xcalak, on the southern part of the Mexican Caribbean coast, proved to belong to two undescribed species of Monstrilla Dana, 1849. They are described here as M. xcalakensis sp. nov. and M. annulata sp. nov., partly by use of scanning electron microscopy. Females of the two species are generally similar but differ in: (1) antennular segmental structure, (2) antennular armature and ornamentation, (3) structure and setation of the fifth leg, (4) number and modifications of the caudal setae, and (5) integumental ornamentation. Comparison with congeneric species revealed distinctive features for both species that support their status as new. These two species are interesting additions to the reef-dwelling monstrilloid copepod fauna of the Mexican Caribbean and confirm Monstrilla as the most diverse genus of monstrilloids in this area, now represented by nine species.


Cruz Lopes da Rosa J., Dias C.O., Suárez-Morales E., Weber L.I. & Gomes Fischer L. 2021. Record of Caromiobenella (Copepoda, Monstrilloida) in Brazil and discovery of the male of C. brasiliensis: morphological and molecular evidence. Diversity 13: 241.

Dakin W.J. & Colefax A.N. 1940. The Plankton of the Australian Coastal Waters off New South Wales, Part 1. University of Sydney, Department of Zoology, Monograph 1: 1–215.

Garm A. & Watling L. 2013. 6. The crustacean integument: setae, setules, and other ornamentation. In: Watling L. & Thiel M. (eds) The Natural History of the Crustacea. Functional Morphology and Diversity: 167–198. Oxford University Press, Oxford.

Grygier M.J. 1994 [dated 1993]. Identity of Thaumatoessa (= Thaumaleus) typica Krøyer, the first described monstrilloid copepod. Sarsia 78: 235–242.

Grygier M.J. 1995. Annotated chronological bibliography of Monstrilloida (Crustacea: Copepoda). Galaxea 12: 1–82.

Grygier M.J. & Ohtsuka S. 1995. SEM observation of the nauplius of Monstrilla hamatapex, new species, from Japan and an example of upgraded descriptive standards for monstrilloid copepods. Journal of Crustacean Biology 15: 703–719.

Grygier M.J. & Ohtsuka S. 2008. A new genus of monstrilloid copepods (Crustacea) with anteriorly pointing ovigerous spines and related adaptations for subthoracic brooding. Zoological Journal of the Linnean Society 152: 459–506.

Grygier M.J. & Suárez-Morales E. 2021. Recognition and partial solution of nomenclatural issues involving copepods of the family Monstrillidae (Crustacea: Copepoda: Monstrilloida). Zootaxa 4486: 497–509.

Huys R. & Boxshall G.A. 1991. Copepod Evolution. The Ray Society 159, London.

Huys R., Llewellyn-Hughes J., Conroy-Dalton S., Olson P.D., Spinks J.N. & Johnston D.A. 2007. Extraordinary host switching in siphonostomatoid copepods and the demise of the Monstrilloida: integrating molecular data, ontogeny and antennulary morphology. Molecular Phylogenetics and Evolution 43: 368–378.

Isaac M.J. 1975. Copepoda, Suborder: Monstrilloida. Fiches d’Identification du Zooplancton 144/145: 1–10.

Jeon D., Lee W. & Soh H.Y. 2018a. A new genus and two new species of monstrilloid copepods (Copepoda: Monstrillidae): integrating morphological, molecular phylogenetic, and ecological evidence. Journal of Crustacean Biology 38: 45–65.

Jeon D., Lim D., Lee W. & Soh H.Y. 2018b. First use of molecular evidence to match sexes in the Monstrilloida (Crustacea: Copepoda), and taxonomic implications of the newly recognized and described, partly Maemonstrilla-like females of Monstrillopsis longilobata Lee, Kim & Chang, 2016. PeerJ 6: e4938.

Sale P.F., McWilliams P.S. & Anderson D.T. 1976. Composition of the near-reef zooplankton at Heron Reef, Great Barrier Reef. Marine Biology 34: 59–66.

Scott T. 1904. The Copepoda of the Siboga Expedition. Part I. Free-swimming, littoral and semi-parasitic Copepoda. Siboga-Expeditie 29a: 1–323. Available from [accessed 5 Dec. 2023].

Silva-Briano M., Adabache A. & Guerrero-Jiménez G. 2013. Additions to the taxonomy of Brachionus josefinae (Rotifera: Monogononta: Brachionidae). Hidrobiológica 23: 450–455.

Suárez-Morales E. 1993. Two new monstrilloids (Copepoda: Monstrilloida) from the coastal area of the Mexican Caribbean Sea. Journal of Crustacean Biology 13: 349–356.

Suárez-Morales E. 1994. Monstrilla elongata, a new monstrilloid copepod (Crustacea: Copepoda: Monstrilloida) from a reef lagoon of the Caribbean coast of Mexico. Proceedings of the Biological Society of Washington 107: 262–267.

Suárez-Morales E. 1996. On a tropical subspecies of Monstrilla wandelli (Copepoda, Monstrilloida) from the Mexican coasts of the Caribbean Sea. Crustaceana 69: 34–40.

Suárez-Morales E. 1998. On the male of Monstrilla mariaeugeniae Suárez-Morales & Islas-Landeros (Copepoda, Monstrilloida) from the Mexican Caribbean Sea. Crustaceana 71: 360–362.

Suárez-Morales E. 2000a. A new species and new geographic records of Monstrilla (Copepoda: Monstrilloida) from the Philippines. Journal of Crustacean Biology 20: 680–686.

Suárez-Morales E. 2000b. Taxonomic report on some monstrilloids (Copepoda, Monstrilloida) from Toulon Bay, France. Bulletin de l’Institut royal des Sciences naturelles de Belgique, Biologie, 70: 107–118.

Suárez-Morales E. 2001. Taxonomic report on a collection of monstrilloids (Copepoda: Monstrilloida) from Banco Chinchorro, Mexico with description of a new species. Anales del Instituto de Biología, Universidad Nacional Autónoma de Mexico 72: 9–28.

Suárez-Morales E. 2003. Three species of monstrilloids (Copepoda: Monstrilloida) from Banco Chinchorro, Mexican Caribbean Sea. Bulletin of Marine Science 73: 63–75.

Suárez-Morales E. 2010. On the taxonomic status of Monstrilla leucopis Sars (Crustacea: Copepoda: Monstrilloida) from Norway, with comments on the male of M. longiremis Giesbrecht. Zootaxa 2510: 55–67.

Suárez-Morales E. 2011. Diversity of the Monstrilloida (Crustacea: Copepoda). PLoS ONE 6: e22915.

Suárez-Morales E. 2018. Monstrilloid copepods: the best of three worlds. Bulletin of the Southern California Academy of Sciences 107: 92–103.

Suárez-Morales E. 2019. A new genus of the Monstrilloida (Copepoda) with large rostral process and metasomal spines, and redescription of Monstrilla spinosa Park, 1967. Crustaceana 92: 1099–1112. https:/

Suárez-Morales E. 2022a. A new species of Monstrilla (Crustacea: Copepoda: Monstrilloida: Monstrillidae) collected by the R/V Albatross (1908) from the Sulu Sea, Philippines. Journal of Natural History 55: 3041–3052.

Suárez-Morales E. 2022b. A new species of Monstrilla (Copepoda, Monstrilloida) from the western Caribbean with comments on M. wandelii Stephensen, 1913 and M. conjunctiva Giesbrecht, 1893. ZooKeys 1128: 33–45.

Suárez-Morales E. & Escamilla J.B. 2001. Taxonomic report on some monstrilloids (Copepoda, Monstrilloida) from southeast Mexico with the description of a new species of Monstrilla. Journal of Natural History 35: 1433–1445.

Suárez-Morales E. & Gasca R. 2004. On the invalidity of Strilloma Isaac (Copepoda: Monstrilloida): observations from the type species. Zoological Studies 43: 292–299.

Suárez-Morales E. & Gasca-Serrano R. 1992. A new species of Monstrilla from the Mexican coasts of the Caribbean Sea. Crustaceana 63: 301–305.

Suárez-Morales E. & Grygier M.J. 2021. Mediterranean and Black Sea monstrilloid copepods (Copepoda: Monstrilloida): rediscovering the diversity of transient zooplankters. Water 13: 1036.

Suárez-Morales E. & Islas-Landeros M. 1993. A new species of Monstrilla (Copepoda: Monstrilloida) from a reef lagoon off the Mexican coast of the Caribbean Sea. Hydrobiologia 271: 45–48.

Suárez-Morales E. & McKinnon A.D. 2014. The Australian Monstrilloida (Crustacea: Copepoda) I. Monstrillopsis Sars, Maemonstrilla Grygier & Ohtsuka, and Australomonstrillopsis gen. nov. Zootaxa 3779: 301–340.

Suárez-Morales E. & Palomares-García R. 1995. A new species of Monstrilla (Copepoda: Monstrilloida) from a coastal system of the Baja California Peninsula, Mexico. Journal of Plankton Research 17: 745–752.

Suárez-Morales E., Harris L.H., Ferrari F.D. & Gasca R. 2014. Late postnaupliar development of Monstrilla sp. (Copepoda: Monstrilloida), a protelean endoparasite of benthic polychaetes. Invertebrate Reproduction & Development 58: 60–73.

Suárez-Morales E., Vásquez-Yeomans L. & Santoya L. 2020. A new species of the Cymbasoma longispinosum species-group (Copepoda, Monstrilloida) from Belize, western Caribbean. Revista mexicana de Biodiversidad 91: e913176.

How to Cite
Suárez-Morales, E. (2024). Two new species of Monstrilla (Copepoda: Monstrilloida: Monstrillidae) from a protected reef system of the Mexican Caribbean. European Journal of Taxonomy, 917(1), 152–169.
Research article