Cyclopoma

{{Short description|Extinct genus of fishes}}

{{Automatic taxobox

| fossil_range = {{fossil range|55.8|45|Ypresian to Lutetian}}

| image = Cyclopoma gigas.jpg

| image_caption = Specimen of C. gigas

| taxon = Cyclopoma

| authority = Agassiz, 1833

| subdivision_ranks = Species

| subdivision = * {{extinct}}C. folmeri Weems, 1999

• {{extinct}}C. gigas Agassiz, 1833
• {{extinct}}C. spinosum Agassiz, 1833

| synonyms = * Smerdis Agassiz, 1833 (in part)

}}

Cyclopoma (from {{langx|el|κύκλος}} {{Transliteration|el|cyclos}}, 'circular' and {{langx|el|πῶμᾰ}} {{Transliteration|el|pôma}} 'cover'){{cite book |last1=Roberts |first1=George |title=An etymological and explanatory dictionary of the terms and language of geology |date=1839 |publisher=Longman, Orme, Brown, Green, & Longmans |location=London |page=40 |url=https://archive.org/details/anetymologicala00robegoog |access-date=29 December 2021 |language=English}} is an extinct genus of marine percomorph fish from the Eocene. It is known from the Ypresian to the Lutetian of Europe and eastern North America.{{Cite web |title=PBDB Taxon |url=https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=36001 |access-date=2024-08-13 |website=paleobiodb.org}}

It is alternatively classified in either the Percichthyidae (which otherwise contains only species from South America and Australia) or in the Centropomidae (represented by modern snooks).{{Cite journal |last1=Carnevale |first1=G. |last2=Bannikov |first2=Alexandre F. |last3=Marramà |first3=G. |last4=Tyler |first4=James C. |last5=Zorzin. |first5=R. |date=2014 |title=The Bolca Fossil-Lagerstätte: A window into the Eocene World. 5. The Pesciara- Monte Postale Fossil-Lagerstätte: 2. Fishes and other vertebrates. Excursion guide |url=https://iris.unito.it/bitstream/2318/149338/1/Carnevale%20et%20al%202014%20The%20Pesciara%20F-L.%20Fishes%20and%20other%20vertebrates2.pdf |journal=Rendiconti della Società Paleontologica Italiana |volume=4 |issue=1 |pages=i–xxvii |hdl=10088/25678}}{{Cite journal |last=Petit |first=Gilles |date=2010 |title=Skin nodules in fossil fishes from Monte Bolca (Eocene, Northern Italy) |url=http://www.bioone.org/doi/abs/10.5252/g2010n1a5 |journal=Geodiversitas |language=en |volume=32 |issue=1 |pages=157–163 |doi=10.5252/g2010n1a5 |issn=1280-9659}}{{Cite journal |last=Alexander |first=Bannikov |date=2008 |title=TWO NEW GENERA FOR LONG KNOWN PERCOID FISHES (PERCIFORMES) FROM THE EOCENE OF BOLCA, ITALY |url=https://www.researchgate.net/publication/266088256 |journal=Bollettino del Museo Civico di Storia Naturale di Verona}}

The following species are known:

• †C. folmeri Weems, 1999 - Ypresian of Virginia, USA (Nanjemoy Formation){{Cite book |url=https://searchworks.stanford.edu/view/4718692 |title=Early Eocene vertebrates and plants from the Fisher/Sullivan site (Nanjemoy Formation) Stafford County, Virginia |date=1999 |publisher=Commonwealth of Virginia, Dept. of Mines, Minerals and Energy, Division of Mineral Resources |editor-last=Weems |editor-first=R. E. |series=Virginia Division of Mineral Resources publication |location=Charlottesville, Va |editor-last2=Grimsley |editor-first2=Gary J.}}
• †C. gigas Agassiz, 1833 - Ypresian of Monte Bolca, Italy (=Amia indica Volta, 1796, Smerdis micracanthus Agassiz, 1833){{Cite book |last1=Geology |first1=British Museum (Natural History) Department of |url=https://books.google.com/books?id=ZtEKAQAAIAAJ |title=Catalogue of the Fossil Fishes in the British Museum (Natural History): Actinopterygian Teleostomi of the suborders Isospondyli (in part), Ostariophysi, Apodes, Percesoces, Hemibranchii, Acanthopterygii, and Anacanthini |last2=Woodward |first2=Arthur Smith |date=1901 |publisher=order of the Trustees |language=en}}
• †C. spinosum Agassiz, 1833 - Ypresian of Monte Bolca, Italy (not recognized in more recent reviews)

An indeterminate species is known from the Lutetian-aged Lutetian limestone of France.{{Cite journal |last=GAUDANT |first=J |date=1982 |title=DECOUVERTE DU GENRE CYCLOPOMA AGASSIZ (POISSON TELEOSTEEN, PERCOIDEI) DANS LE CALCAIRE GROSSIER D'ILE-DE-FRANCE |url=https://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=PASCALGEODEBRGM8220318963 |journal=Decouverte du Genre Cyclopoma Agassiz (Poisson Teleosteen, Percoidei) dans le Calcaire Grossier d'Ile-De-France}}

File:FMIB 36062 Cyclopoma Spinosum, Agass.jpeg

As its name suggests, C. gigas was a large fish that could reach up to {{Convert|0.5|m|ft}} in length. It likely inhabited brackish waters close to river mouths.{{Cite journal |last1=Andrea Papazzoni |first1=Cesare |last2=Trevisani |first2=Enrico |date=2006-11-24 |title=Facies analysis, palaeoenvironmental reconstruction, and biostratigraphy of the "Pesciara di Bolca" (Verona, northern Italy): An early Eocene Fossil-Lagerstätte |url=https://www.sciencedirect.com/science/article/pii/S0031018206003178 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=242 |issue=1 |pages=21–35 |doi=10.1016/j.palaeo.2006.05.011 |bibcode=2006PPP...242...21A |issn=0031-0182}}

It has been alleged that Louis Agassiz struggled with excavating the type specimen of C. spinosum, despite continuously studying it. For two nights, he dreamed of the specimen appearing fully restored, and on the third night, sketched his vision of the restored specimen while half-awake. When he continued preparing the fossil specimen the following day, the fully excavated specimen was allegedly found to be exactly as he had dreamed and sketched.{{Cite journal |last=Duffin |first=Christopher J. |date=2007 |title=Louis Agassiz (1807–1873): a passion for fishes |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2451.2007.00615.x |journal=Geology Today |language=en |volume=23 |issue=4 |pages=132–142 |doi=10.1111/j.1365-2451.2007.00615.x |bibcode=2007GeolT..23..132D |issn=0266-6979}}{{Cite web |title=Elizabeth Cary Agassiz, Louis Agassiz: his life and correspondence, third edition, Chapter 5: 1830-1832: Aet. 23-25. |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:2001.05.0258:chapter=6&highlight=cyclopoma |access-date=2024-08-13 |website=www.perseus.tufts.edu}}