Metadata for the checklists and species accounts


Suprageneric classification and order of classification follow V4 of the phylogenetic classification of bony fishes (Betancur-R, Wiley, Arratia, Acero, Bailly, Miya, Lecointre and Ortí 2017). Generic placement generally follows Nelson, Grande and Wilson (2016) and specific studies of individual taxa.

Data from the following sources have been used:

Currently accepted name combinations are followed by their original author and date and by revisers (if any, following International Code of Zoological Nomenclature Recommendation 51G). Other names which have been used (synonyms, previous combinations and misidentifications) are indented and follow immediately after the current name for the species. Author names and dates in [square brackets] are for taxa which have not been formally described, and identify the source with most information about that particular taxon. The checklist conforms to the ideas in Dubois (2017).

IUCN Red List categories and criteria

Where a conservation assessment has been carried out, and valid IUCN Red list categories and criteria have been assigned, details are included in superscript square brackets. The notation for this is as follows:

[Category and Criteria:Redlist Version number:Year of evaluation] e.g. [EN B2ab(iii):3.1:2014]. Each assesment is linked to the relevant Red List entry.

See for full details of these categories and the criteria by which they are defined.

The version of Categories and Criteria under which the species was assesed are given as follows:

Categories and Criteria V2.3: An early formulation published in 1994.

Categories and Criteria V3.1: The currently used formulation published in 2001.

The date (year) in which the assessment was made is provided after the version number.

In the USA and Brazil there are instances where assessments have been made using the IUCN Categories and Criteria (in all cases to V3.1) but where these have not been uploaded to the IUCN Red List web site. In these cases the IUCN assessment is provided first and the other assessment second. For the US species all assessments are included in Niemiller et al. (2013) and for the Brazilian species at:

Other Notation

Note: For the genus Sinocyclocheilus (Cypriniformes: Cyprinidae) in China the lineage (clade) of each species is indicated by letters as follows: [A] angularis (13 species), [C] cyphotergous (14 species), [T] tingi (3 species). There are no known troglobiotic members of the fourth clade, jii. Information from Zhao and Zhang (2009), Romero, Zhao and Chen (2009), Chen, Luo, Xiao and Yang (2010), Zhao, Gozlan and Zhang (2011) and Yahui Zhao (pers. comm.).

References to the original description for all formally described species can be obtained from Eschmeyer, Fricke and van der Laan (2019). References to species in the list which have been reported in the literature, but not yet formally described [references in square backets] are provided in the searchable bibliography

DRC = Democratic Republic of Congo (formerly Zaire), PNG = Papua New Guinea

Subterranean fish species by country

Provide a description/analysis

Country Species % Described Undescribed First year  
China 91 31.49 90 1 1931  
Brazil 44 15.22 23 21 1905  
USA 21 7.27 10 11 1842  
India 18 6.23 17 1 1872  
Mexico 18 6.23 12 6 1936  
Colombia 10 3.46 7 3 2006 6=202 70%
Cuba 9 3.11 4 5 1858  
Thailand 9 3.11 9 0 1988  
Venezuela 7 2.42 3 4 1994  
Vietnam 7 2.42 7 0 1978  
Japan 5 1.73 5 0 1940  
Madagascar 5 1.73 4 1 1933  
Iran 4 1.38 4 0 1944  
Australia 3 1.04 3 0 1945  
Indonesia 3 1.04 3 0 1868  
Iraq 3 1.04 3 0 1955  
Laos 3 1.04 3 0 1999  
Oman 3 1.04 2 1 1977  
Philippines 3 1.04 3 0 1991  
Somalia 3 1.04 3 0 1923  
Bahamas 2 0.69 2 0 1970  
Bolivia 2 0.69 2 0 1968  
Ecuador 2 0.69 1 1 1962  
PNG 2 0.69 2 0 1996  
Argentina 1 0.35 1 0 2005  
Belize 1 0.35 1 0 1982  
Cameroon 1 0.35 1 0 2016  
DRC 1 0.35 1 0 1921  
Galapagos 1 0.35 1 0 1965  
Germany 1 0.35 0 1 2017  
Malaysia 1 0.35 1 0 1990  
Myanmar 1 0.35 1 0 2020  
Namibia 1 0.35 1 0 1936  
Peru 1 0.35 1 0 1994  
Trinidad 1 0.35 1 0 1926  
Turkmenia 1 0.35 1 0 1983  
36 Countries 289 as of May 2022 100% 233 56   30=87 30%

PNG = Papua New Guinea, DRC = Democratic Republic of the Congo

The bibliography

Of course not all of the entries in the bibliography are solely concerned with aspects of subterranean fish biology. Some are studies relating to the physical and hydrological environment the fishes live in (e.g. Fish 2004), some to the biology of other animals in the fishes environment which may be part of the food supply (e.g. Silva et al. 2011). Generally speaking any refrerence source which could potentially enhance an understanding of the whole biology of the fish is included and the aim is always to include if even vaguely relevant rather than exclude.

The Classification of subterranean organisms

The following sources describe the terms used to differentiate between different ecological categories of subterranean animals: Racovitza (1907), Camacho (1992), Polak (1997), Sket (2008), Trajano (2012), Trajano and Carvalho (2017), Giachino and Vailati (2017), Culver and Pipan (2019)Martinez and Mammola (2020, 2021)

Habitat types (section in preparation)

Many subterranean animals, including at least 22 subterrean fishes, live in anchialine habitats (also spelled anchihaline) at the margin of land and sea. There have been numerous definitions of this habitat but the most recent is provided by Bishop et al. (2015). Reviews of achialine environments are provided by Iliffe and Kornicker (2009), Iliffe (2000) and Bishop, Humphreys and Jaume (2020). Hengstum et al. (2019) is an important review of anchialine cave development in the Pleistocene. The World Register of Marine Cave Species (WoRCS) is a major collection of information on marine cave species, and is described in detail in Gerovasileiou et al. (2016). A larger version of this for all stygofauna is briefly described in Martinez et al. (2018).

Museum acronyms

You can determine where specimens are depoisted using the search facility in Fricke and Eschmeyer’s (2017) Guide to fish collections in the Catalog of Fishes. Also, the American Society of Ichthyologists and Herpetologists list of Standard symbolic codes for institutional resource collections in herpetology and ichthyology.

Links within each species account

The name heading links to the Fishbase account for the species. Many of these accounts are very poorly populated and offer little that the species accounts here provide. However, they do offer links to the separate genera and species databases within the Catalog of Fishes. The first line of the account has an “Catalog of Fishes (gen., sp.)” entry and these two links will go direct to the genera and species information within the Catlog of Fishes. The Family name links back to the species name in the checklist.

The images which illustrate the species accounts

A single click on any image will enable a full-screen view. This is particularly impressive where the image is a photograph.

Geographical distribution of cave and groundwater fishes

The geographical location of each species of cave and groundwater fishes are provided at the following two web sites as part of the Biofresh Project (Proudlove and De Wever 2017)

Maps and coordinates Zoom in on the map to get all geographical locations for these species. Click the green Occurrences button to get a list of coordinates.

Latitude and longitude data Go to the link, download the DwC-A file, unzip it, open the occurence.txt file in Excel, Open Office or Libre Office.

A note on molecular methods

A nomenclature for the use of molecular methods on type and non-type specimens is proposed by Chakrabarty (2010) and Chakrabarty, Warren, Page and Baldwin (2013). Also useful for molecular studies are Porter (2007) and Juan et al. (2010).

Aspects of envoronmental DNA studies in subterranean environments are discussed by Sacco et al. (2022).

A note on morphological studies

Despite much stress being given to molecular methods to identify species, and to study the relationships among related taxa, morphology still has an important role in ichthyology. In this regard the paper by Dahdul et al. (2010) and its associated web site are critical resources for all ichthyologists.

Comparisons of subterranean fishes with deep-ocean fishes

The following provide information about deep-ocean fishes, some of which loose their eyes: Wang et al. (2019)

Sources of information on fish biology

There are three web sites of incomparable value to the student of ichthyology: the Catalog of Fishes (Eschmeyer, Fricke, and van der Laan 2019) which is the authoritative sources on systematics and nomenclature, the Welt der Fische / World of Fishes (Schraml 2019) which provided very fast details of new species as they are published, and Fishbase (Froese and Pauly 2019). which provides details of many aspects of fish biology. The best introductions to fish biology are Bond's Biology of Fishes (Barton 2007), The Diversity of Fishes (Helfman, Collette, Facey and Bowen 2009) and Essential fish biology (Burton and Burton 2018). Helfman's Fish Conservation (Helfman 2007) is also a critical resource. A modern brief overview of cavefishes is provided by Borowsky (2018).

Sources of information for subterranean biology

The following books will provide a thorough grounding in all aspects of subterranean biology:

Culver (1982) reprinted 2013

Gunn (2004)

Culver and White (2005)

Trajano, Bichuette and Kapoor (2010)

White and Culver (2012)

Wilkens, Culver and Humphries (2000)

Culver and Pipan (2009, 2019)

Culver and Pipan (2014)

Engel (2015)

Beltram (2018)

Sket (2018)

Froend et al. (2018)

Moldovan et al. (2018)

White, Culver and Pipan (2019)

Sacco et al. (2019)

Wynne (2022)

The following publications are very recent commentaries on aspects of cave research and will be profitably read by all interested in caves and subterranean biology in general

Aljancic (2019)

Itescu (2019)

Mammola (2019)

Mammola (2020)

Mammola and Martinez (2020)

Mammola et al. (2020)

Mammola et al. (2020)

Martinez and Mammola (2020)

Romero (2020)

Sanchez-Fernandez et al. (2018)

Sources of information on karst, caves and hydrogeology

Ford and Williams (2007)

Palmer (2007)

Shaw (1992)

Martin and Shaw (2008)

White and Culver (2007)

Definition of "cave"

Sources of information for subterranean fishes

The following books will provide a thorough grounding in all aspects of subterranean fishes:

Tajano, Bichuette and Kapoor (2010)

Romero (2001)

Thines (1969)

Proudlove (2006)

Web based sources if information

International Society for Subterranean Biology (SIBIOS) and Facebook

William R. Elliott's web site

Karst Waters Institute

British Cave Research Association

Currency of the details within this website

The aim is that the checklist, which forms the main route into the site, and acts as an index, will always be up to date, and where it is not it will be no more than one month out of date (easy to achieve using the invaluable World of Fish website). The species accounts will always be works in progress and will rarely, if ever, get to a status of up to date and complete as it is always possible to add further details. If you are interested in a particular species let me know and I will endevour to produce the most complete account as I can for that species. All pages within the site are date stamped with their last date of editing so you can see how old an account is.