Modifications in the Fish Classification in FishBase
Important note: The FishBase database and website must not be considered as publications for nomenclatural purposes. If a name would be demonstrated as new, it must be considered as not available under the ICZN provisions, Art. 8.2 (International Code of Zoological Nomenclature).
The position of the Scaridae/Scarinae/Scarini – parrotfishes (July 2023)
The Scaridae have been recognized as a valid taxonomic group since Rafinesque, 1810 (Van der Laan et al., 2014 and subsequent addenda), either as a subfamily or a sister-family of the Labridae. Hughes et al. (2023) proposed a phylogenomic analysis of large genome-wide sequence data sets to resolve the sister-group of Labridae (confirmed to be the Centrogenyidae as in Betancur-R et al., 2017) and the relationships inside the family. This study confirms the placement of Scaridae as a sub-group within the Labridae, which was already demonstrated by Westneat and Alfaro (2005) and subsequent works (see the introduction in Hughes et al., 2023, incl. Betancur-R et al., 2017). However, this latter result was not reflected in Catalog of Fishes (until Hughes et al. 2023) and FishBase.
FishBase is subjected to several constraints as detailed below (section Changes in March 2021) to propose a simplified classification. So far, none of the previous works presented a rather complete phylogeny for Labridae, as explained by Hughes et al. (2023), to derive such a classification. And still some issues remain.
Scaridae is a well-known group among the public, divers, small-scale fishermen, aquarist hobbyists, …, and an important source of subsistence food in coral-reef areas. In the technical current situation of FishBase, integrating the Scaridae into the Labridae would render the parrotfishes invisible in FishBase as a group, and would generate confusion for the public, and for fisheries statistics. Indeed, subfamilies are recorded in FishBase but at the species level classification where they cannot be searched on the web, unlike orders and families. Moreover Hughes et al. (2023) use the tribe rank, not the subfamily one, probably to denote the remaining issues.
There are 3 options to change the classification of Labridae to reflect the important result of Hughes et al. (2023), which are not mutually exclusive:
- We change the structure of the database to make subfamilies and tribes visible as taxa (this has been already considered but requires a quantity of work that we could not allocate so far);
- a work is published with the complete list of genera, each allocated to one subfamily according to the phylogeny of Hughes et al. (2023), with as few as possible as incertae sedis;
- subfamilies are uplifted to family ranks within the Labroidei.
In other words, if we did not include the Scaridae in Labridae before, it is not because we rejected the works of M. Westneat and other colleagues, but because in the current status of knowledge and technology, it is difficult to integrate phylogenetic works into a simplified classification framework without confusing the public by certain drastic changes.
We would like to develop a phylogenetic module that would incorporate in “real-time” the most recent results, allowing to search for biological and ecological information using this (or competing) phylogenetic backbone. We welcome realistic partnership propositions!
Changes in February 2023
Since the previous major update in March 2021 (see below), we made a further change by replacing the class Actinopteri (that was confusing with Actinopterygii) by three classes, namely Chondrostei (sturgeons and paddlefishes), Holostei (bowfins and gars), and Teleostei (teleosts). These three groups and their names are currently valid but at ranks intermediary between Class and Order. We just uplifted them at class rank to highlight the Teleostei as a group in our simplified classification, which was missing up to now.
- Myxini
- Petromyzonti
- Elasmobranchii
- Holocephali
- Cladistii
- Chondrostei
- Holostei
- Teleostei
- Coelacanthi
- Dipneusti
De facto, this flattened classification fails to represent the phylogenetic relationships, that should be read as follows (the phylogeny is also simplified).
Note that the 10 classes above are noted in bold:
- Agnatha
- Gnathostomata
- Chondrichthyes
- Elasmobranchii
- Holocephali
- Osteichthyes
- Actinopterygii
- Sarcopterygii
- Coelacanthi
- Dipnotetrapodomorpha
Changes in March 2021
The latest edition of Fishes of the World – FoW (Nelson et al., 2016) integrated the recent wide-scope phylogenetic studies (e.g., Betancur-R et al., 2013, as DF for DeepFin, and others) resulting in a large re-organization of the bony fish classification at the top of the tree, i.e., Perciformes and Scorpaeniformes, and allies. We waited that the community supports these major changes, especially Catalog of Fishes (ECoF), which seems to be broadly the case despite some necessary continuous adjustments. This re-arrangement was postponed by Nelson in the previous FoW edition (2006, see comments under Scorpaeniformes) because he estimated rightly that the scopes of the studies at that time were not large enough.
Here are the constraints we followed:
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Still limiting the number of ranks in the classification to keep it simple: class, order, family, subfamily, genus, species. It is understood that doing so, some phylogenetic relationships are lost, but it is a balance with keeping the classification more easily manageable: the complete phylogeny that is mainly dichotomic by nature is difficult to represent and master as a hierarchy.
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Following Betancur-R et al. (2017 as DF2017) phylogeny general structure. The lower part of it was mostly endorsed by FoW2016 and ECoF.
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Following DF2017 for the sequence of orders.
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Following DF2017 for the divisions in 9 series of the former Percomorpha (= their Percomorphacae), group which was known as the “bush at the top” (G. Nelson, 1994): Ophidiaria, Batrachoidaria, Pelagiaria, Syngnatharia, Gobiaria, Anabantaria, Carangaria, Ovalentaria, Eupercaria. Although these are not listed in the FB classification, the sequence of orders follows these series.
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Following ECoF for the sequence of families in each order.
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Not following DF2017 nor FoW2016 in recognizing some orders with one family derived for the previous Perciformes (orders that are quite different in both publications). Rather we follow ECoF in gathering the families of these orders in incertae sedis groups but still along the series Betancur-R et al. schema (called ‘/misc’ here).
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Keeping as orders some groups well-defined morphologically rather than gathering them as suborders of one of them, e.g., in ECoF Pleuronectiformes is a suborder of Carangiformes.
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Following FoW2016 and ECoF for some family/subfamily issues, especially when the family was not examined in DF2017.
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Under these constraints, adapting logically the classification in a few places, e.g., by raising the suborders of Syngnathiformes to orders.
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No new name was created in purpose. If there are, it is by mistake, this work must not be considered for nomenclature purposes.
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Following some recent changes (e.g., Acanthuriformes) endorsed by ECoF.
Besides the bony fishes, Rays of the World (Last et al., 2016) made a number of changes after FoW2016 in Batoidea, but they were already integrated.
Main changes:
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8 classes instead of 6.
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Lampreys, that were included in Cephalaspidomorphi, a group for fossils only, are placed under Petromyzonti.
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Actinopterygii are made a superclass with two classes: Cladistii (Polypteriformes), Actinopteri.
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Sarcopterygii are made a superclass with two classes: Coelacanthi, Dipneusti.
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Carangaria/misc, Ovalentaria/misc, and Eupercaria/misc contain families that are either incertae sedis or that are placed in their own order in FoW2016 or DF2017. In some cases, their position in these three series is not always well supported. In some cases, unique families in one order have several subfamilies. It would make sense uplifting those at family rank justifying the use of an order (e.g., Labriformes).
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Split of Alepocephaliformes from Osmeriformes.
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Split of Gasterosteiformes in parts placed in different other series/orders.
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Long-time well-defined suborders of Perciformes uplifted at rank order as it was suggested for a while.
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Scorpaeniformes minus some suborders as a suborder of Perciformes.
Complete different treatment of Carangiformes compared to ECoF (version March 2021) where they correspond to the entire series Carangaria in DF2017, making Pleuronectiformes a suborder, which may not be much accepted.
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We have included the suborders of Perciformes within the orders as: Perciformes/Percoidei, Perciformes/Zoarcoidei, Perciformes/Bembropoidei, Perciformes/Percophoidei, Perciformes/Notothenioidei, Perciformes/Uranoscopoidei, Perciformes/Serranoidei, Perciformes/Scorpaenoidei, Perciformes/Gasterosteoidei, Perciformes/Cottoidei.
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A total of 81 formal orders instead of 65; 3 series/misc; 10 Perciformes/suborders in place of Perciformes. Total: 93 order-level groups.
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600 families instead of 590.
The current classification may change in the next 2-3 updates before a more stable classification is established. A comparison between FishBase2020, FoW2017, DF2017 and ECoF will be provided in the next update. Note that the complete DF2017 is available for each family in their family page (except for the newly described or modified ones since). One project is to have an additional page where species are organized along this phylogeny. See also why ECoF and FishBase are not updated at the same time.
Note that the information for orders and families are still being updated and not complete for this update.
Nicolas Bailly,
July 2023
References
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Betancur-R, R.; Broughton, R.E.; Wiley, E.O.; Carpenter, K.; López, J.A.; Li, C.; Holcroft, N.I.; Arcila, D.; Sanciangco, M.; Cureton, J.C.; Zhang, F.; 2013. The tree of life and a new classification of bony fishes. PLoS currents, 5.
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Betancur-R, R.; Wiley, E.O.; Arratia, G.; Acero, A.; Bailly, N.; Miya, M.; Lecointre, G.; Orti, G.; 2017. Phylogenetic classification of bony fishes. BMC evolutionary biology, 17(1): 1-40.
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Hughes, L.C.; Nash, C.M.; White, W.T; Westneat, M.W.; 2023. Concordance and discordance in the phylogenomics of the wrasses and parrotfishes (Teleostei: Labridae). Syst. Biol., 72(3): 530-543. [online Nov., 2022]
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Last, P.R.; White, W.T.; Carvalho, M.R. de; Séret, B.; Stehmann, M.F.W.; Naylor, G.J.P.; 2016. Rays of the world. CSIRO Publishing, Comstock Publishing Associates. i-ix + 1-790.
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Nelson, G.; 1989. Phylogeny of major fish groups. In: Fernholm, B.; Bremer, K.; Brundin, L.; Jörnvall, H.; Rutberg, L.; Wanntorp, H.E.; editors. The Hierarchy of Life: molecules and morphology in phylogenetic analysis. Amsterdam: Elsevier Science; 1989: 325-336.
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Nelson, J.S.; 2006. Fishes of the World. 4th ed. Hoboken (New Jersey, USA): John Wiley & Sons. xix+601 p.
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Nelson, J.S.; Grande, T.C.; Wilson ; M.V.H.; 2016. Fishes of the world. Fifth edition. Hoboken, New Jersey: John Wiley & Sons, 707 p.
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Van der Laan, R.; Eschmeyer, W.N.; Fricke, R.; 2014. Family-group names of recent fishes. Zootaxa 3882(1): 1-230.
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Westneat, M.W.; Alfaro M.E.; 2005. Phylogenetic relationships and evolutionary history of the reef fish family Labridae. Mol. Phylogenet. Evol. 36: 370-390.