Inventory of Caribbean Polyclads

Department of Natural Resources

College of Life Sciences and Agriculture

University of New Hampshire



A Modern Inventory of the Polyclad Fauna of the Caribbean: Distribution, Systematics and Taxonomy

The Polycladida represents a highly diverse clade of free-living marine turbellarian flatworms. Traditionally, taxonomic study of this group is based on details of the reproductive anatomy. Using morphological and molecular characteristics, we are developing evolutionary hypotheses of relationships within the group and within the phylum Platyhelminthes.

In this project, we are collecting new and known species of Caribbean polyclads for accession into museums and into a large, web-based database. Collected specimens are fixed for histology and preserved for DNA analysis. Field data, images, and associated references are linked to individual specimens. Detailed taxonomic information, DNA and tissue vouchers, DNA sequences, and images for each species are collected and included in the database.


  • Quiroga SY, Bonilla EC, Bolaños DM, Carbayo F, Litvaitis MK, Brown FD. 2015. Evolution of flatworm central nervous systems: Insights from polyclads. Genetics Mol Biol 38:233-248 (pdf)
  • Liana MK, Quiroga SY, Bolaños DM, Litvaitis MK. 2012. Comparative morphology of the epidermis of seven species of polyclad flatworms (Platyhelminthes: Rhabditophora). Zool Anz 251: 206-214 (pdf)
  • Liana MK, Litvaitis MK. 2010b. Ultrastructure of the spermatozoa of the flatworms Phaenocelis peleca and Boninia divae (Platyhelminthes, Polycladida). Zoomorphology 129: 221-224 (pdf)
  • Litvaitis MK, Bolaños DM, Quiroga SY. 2010. When names are wrong and colours deceive: Unravelling the Pseudoceros bicolor species complex (Playthelminthes: Polycladida). J Nat Hist 44: 829-845 (pdf)
  • Liana MK, Litvaitis MK. 2010a. Anatomy and ultrastructure of the male reproductve system of Pleioplana atomata (Platyhelminthes: Polycladida). Invert Biol 129: 129-137 (abstract)
  • Bolaños DM, Litvaitis MK. 2009. Embryonic muscle development in direct and indirect developing marine flatworms (Platyhelminthes: Polycladida). Evol Dev 11: 290-301 (pdf)
  • Liana MK, Litvaitis MK. 2009. Anatomy and ultrastructure of the female reproductve system of Pleioplana atomata (Platyhelminthes: Polycladida). J Morphol 270: 337-343 (pdf)
  • Rawlinson KA, Bolaños DM, Liana MK, Litvaitis MK. 2008. Reproduction, development, and parental care in two direct-developing flatworms (Platyhelminthes: Polycladida: Acotylea). J Nat Hist 42: 2173-2192 (pdf)
  • Quiroga SY, Bolaños DM, Litvaitis MK. 2008. Two new species of polyclad flatworms from the continental slope of the Gulf of Mexico: Didangia carneyi n sp (Acotylea: Didangiidae) and Oligocladus bathymodiensis n sp. J Mar Biol Assoc UK 88: 1363-1370 (abstract)
  • Rawlinson K, LitvaitisMK. 2008. Cotylea (Polycladida): A cladistic analysis of morphology. Invert Biol 127: 121-138 (pdf)
  • Rawlinson KA (2008) Biodiversity of coastal flatworm assemblages in the wider Caribbean. Mar Biol 153: 769-778 (pdf)
  • Cover of Zootaxa: Bolaños DM, Quiroga SY, Litvaitis MK (2007) Five new species of cotylean flatworms (Platyhelminthes: Polycladida) from the wider Caribbean. Zootaxa 1650: 1-23 (pdf)
  • Bolaños DM, Quiroga SY, Litvaitis MK (2006) A new acotylean flatworm, Armatoplana colombiana n. sp. (Platyhelminthes: Polycladida: Stylochoplanidae) from the Caribbean coast of Colombia, South America. Zootaxa 1162: 53-64 (pdf)
  • Quiroga SY, Bolaños DM, Litvaitis MK (2006) First description of deep-sea polyclad flatworms from the North Pacific: Anocellidus n. gen. profundus n. sp. (Anocellidae, n. fam.) and Oligocladus voightae n. sp. (Euryleptidae). Zootaxa 1317:1-19 (pdf)
  • Quiroga SY, Bolaños DM, Litvaitis MK (2004) A checklist of polyclad flatworms (Platyhelminthes, Polycladida) from the Caribbean coast of Colombia, South America. Zootaxa 633: 1-12 (pdf)
  • Quiroga SY, Bolaños M, Litvaitis MK (2004) Policládidos (Platyhelminthes: “Turbellaria”) del Atlántico Tropical Occidental. Polyclads (Platyhelminthes: “Turbellaria”) from the Tropical Western Atlantic. Biota Colombiana 5: 159-172 (pdf)
  • Liana MK, Litvaitis MK. 2007. Comparative spermatology of selected polyclad flatworms (Platyhelminthes). J Morphol 268: 891-897 (pdf)
  • Litvaitis MK, Newman LJ. 2001. A molecular frame work for the phylogeny of the Pseudocerotidae (Platyhelminthes, Polycladida). Hydrobiologia 444: 177-182 (pdf)
  • Litvaitis MK, Rohde K. 1999. A molecular test of platyhelminth phylogeny: Inferences from partial 28S rDNA sequences. Invert Biol 118: 42-56 (pdf)

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black flatworm with orange border

tiger flatworm, adult and juvenile

underside of flatworm showing sperm

phylogenetic diagram

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