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:
- Cypriniformes: Tan and Armbruster (2018)
- Nemacheilidae, Balitoridae and Cobitidae: Tang, Liu, Mayden and Xiong (2006), Slechtova, Bohlen and Tan (2007), Kottelat (2012)
- Cyprininae: Yang et al. (2015)
- Gobiiformes and Butidae: Thacker (2009)
- Phreaobiidae: Sulivan, Muriel-Cunha and Lundberg (2013)
- Milyeringidae: Chakrabarty, Davis and Sparks (2012), Sparks and Chakrabarty (2012)
- Kryptoglanidae: Britz, Kakkassery and Raghavan (2014)
- Dinematichthyidae: Moller, Knudsen, Schwarzhans and Nielsen (2016)
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.
- [NE]: Not evaluated.
- [DD]: Data defficient
- [LC]: Least concern
- [NT]: Near threatened
- [VU]: Vulnerable
- [EN]: Endangered
- [CR]: Critically endangered
- [EW]: Extinct in the wild
- [EX]: Extinct
See iucnredlist.org 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: www.icmbio.gov.br/portal/faunabrasileira/lista-de-especies?start=1
- MG Monotypic subterranean-restricted genus.
- MuG Multitypic subterranean-restricted genus with two or more species.
- HRF Hypogean-restricted Family
- TLO Species known from its type locality only.
- TMP Troglomorphic (and probably troglobiotic) hypogean population of a previously known, and named, epigean fish. These species exhibit some, or many, of the characteristics termed troglomorphy, i.e. they are depigmented and may have a reduction in eye size. Further work is required accurately to assess their status.
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
|36 Countries||289 as of May 2022||100%||233||56||30=87 30%|
PNG = Papua New Guinea, DRC = Democratic Republic of the Congo
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)
- Anchialine habitats
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).
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
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 kb.phenoscape.org 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
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
Sources of information on karst, caves and hydrogeology
Sources of information for subterranean fishes
The following books will provide a thorough grounding in all aspects of subterranean fishes:
Web based sources if information
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.