Lethacotyle

{{Short description|Genus of flatworms}}

{{Automatic taxobox

| image = Journal.pone.0079155.g002 cropped Lethacotyle fijiensis Manter & Prince, 1953, holotype body.tiff

| image_upright = 0.5

| image_alt =

| image_caption = Holotype of Lethacotyle fijiensis Manter & Prince, 1953

| taxon = Lethacotyle

| authority = Manter & Price, 1953

| subdivision_ranks = Species

| subdivision =

• Lethacotyle fijiensis
• Lethacotyle vera

}}

Lethacotyle is a genus of polyopisthocotylean monogeneans, included in the family Protomicrocotylidae.

The genus includes only two species: Lethacotyle fijiensis Manter & Price, 1953

Manter, H. W. & Price, D. F. 1953: Some Monogenetic Trematodes of marine fishes from Fiji. Proceedings of the Helminthological Society of Washington, 20, 105-112.

, the type-species of the genus, and Lethacotyle vera Justine, Rahmouni, Gey, Schoelinck, & Hoberg, 2013

.{{Cite journal|vauthors=((Justine J-L)), Rahmouni C, Gey D, Schoelinck C, Hoberg EP | title = The Monogenean which lost its clamps| doi = 10.1371/journal.pone.0079155| journal = PLOS ONE| year = 2013| pmid = 24278118 | pmc = 3838368| volume=8| issue=11| pages=e79155| doi-access = free}}

Both species are parasitic on the gills of jacks in the Pacific Ocean.Ramalingam, K. 1966: A rare record of Lethacotyle (Monogenea), its post-oncomiracidial larva with observation on distribution. Current Science, 35, 101-102 [http://www.currentscience.ac.in/Downloads/article_id_035_04_0101_0102_0.pdf PDF].Ramalingam, K. 1968: A redescription of Lethacotyle (Monogenea) and its post-oncomiracidial larva. Journal of the Madras University B, 35-36, 107-114. They are known only from three localities: off Fiji, Andaman Islands, and New Caledonia.

The genus Lethacotyle is special in that its members have no clamps on their posterior attachment organ or haptor, in contrast to most polyopisthocotylean Monogenean which have clamps.Bychowsky, B. E. (1961). Monogenetic Trematodes their systematics and phylogeny. English translation edited by W. J. Hargis Jr. Washington: American Institute of Biological Sciences [https://archive.org/details/monogenetictrema00bykh Archive.org].Hayward, C. (2005). Monogenea Polyopisthocotylea (ectoparasitic flukes). In K. Rohde (Ed.), Marine Parasitology (pp. 55-63): CSIRO, Collingwood, Australia & CABI, Oxon, UK. This is reflected in the etymology of the name, which, according to Manter & Price is "from letha = forgetting, and cotyle = cup, and refers to the absence of clamps".