Paralichthyidae

Large-tooth flounders or sand flounders are a family, Paralichthyidae, of flounders.^[1][2] The family contains 14 genera with a total of about 110 species. They lie on the sea bed on their right side; both eyes are always on the left side of the head, while the Pleuronectidae usually (but not always) have their eyes on the right side of the head.

Bigeye flounder, Hippoglossina macrops

Large-tooth flounders
Pacific sanddab, Citharichthys sordidus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Carangiformes
Suborder:	Pleuronectoidei
Family:	Paralichthyidae Chabanaud, 1937
Type genus
Paralichthys Girard, 1858
Genera[1]
Ancylopsetta Cephalopsetta Citharichthys Cyclopsetta Etropus Gastropsetta Hippoglossina Paralichthys Pseudorhombus Syacium Tarphops Tephrinectes Thysanopsetta Xystreurys

They are found in temperate and tropical waters of the Atlantic, Indian and Pacific Oceans.^[3]

Dusky flounder, Syacium papillosum

Several species are important commercial and game fishes, notably the California halibut, Paralichthys californicus and the Pacific sanddab, Citharichthys sordidus.

Phylogenetic analyses have long indicated the non-monophyly of this family e.g.,^[4] and two lineages have been consistently apparent. Termed groups, the two groups were named after genera: a Cyclopsetta group and a Pseudorhombus group (see summary in ^[5]). A formal description of Cyclopsettidae in 2019 created this family consisting of four genera: Cyclopsetta, Etropus, Citharichthys, and Syacium corresponding to the previously recognized Cyclopsetta group.^[5] Molecular phylogenetic evidence indicates that Paralichthyidae in this sense is sister to Pleuronectidae and Cyclopsettidae is sister to Bothidae e.g.^[6]

References

1. Froese, Rainer; Pauly, Daniel (eds.). "Family Paralichthyidae". FishBase. October 2012 version.
2. Kells, V.; and Carpenter, K. (2011). A Field Guide to Coastal Fishes from Maine to Texas. ISBN 978-0-8018-9838-9
3. "Paralichthyidae" World Register of Marine Species. Retrieved 2014-1-26.
4. Pardo, Belén G.; Machordom, Annie; Foresti, Fausto; Porto-Foresti, Fábio; Azevedo, Marisa F. C.; Bañon, Rafael; Sánchez, Laura; Martínez, Paulino (2005-12-30). "Phylogenetic analysis of flatfish (Order Pleuronectiformes) based on mitochondrial 16s rDNA sequences". Scientia Marina. 69 (4): 531–543. doi:10.3989/scimar.2005.69n4531. hdl:10347/22903. ISSN 1886-8134.
5. Campbell, Matthew A.; Chanet, Bruno; Chen, Jhen‐Nien; Lee, Mao‐Ying; Chen, Wei‐Jen (September 2019). "Origins and relationships of the Pleuronectoidei: Molecular and morphological analysis of living and fossil taxa". Zoologica Scripta. 48 (5): 640–656. doi:10.1111/zsc.12372. ISSN 0300-3256. S2CID 202856805.
6. Berendzen, Peter B.; Dimmick, Walter Wheaton (August 2002). McEachran, J. D. (ed.). "Phylogenetic Relationships of Pleuronectiformes Based on Molecular Evidence". Copeia. 2002 (3): 642–652. doi:10.1643/0045-8511(2002)002[0642:PROPBO]2.0.CO;2. ISSN 0045-8511. S2CID 86091999.