Current number of accepted species in our list: 348
This World Database of all species of Kinorhyncha ever described, is part of the World Register of Marine Species (WoRMS), a global initiative to provide a register of all marine organism names. The aim of the World Kinorhyncha Database is to mirror the full hierarchical classification system of Kinorhyncha including unaccepted names and synonymy, the etymology of all scientific names, the distribution data of all published specimens including their deposition or non-deposition in which reference collection, access to molecular data, and all published references on any topic about Kinorhyncha at species level. In this way, the database will hopefully contribute to the stability of taxonomic names and facilitate information and research on all aspects of Kinorhyncha including taxonomy, phylogeny, morphology, development, biology, biogeography, ecology, and molecular biology.
Introduction
Kinorhyncha (mud dragons) is a group of marine and sometimes brackish water meiofaunal animals living on algae, sea grass, kelp, on or in other invertebrates, or in sediments from the intertidal to abyssal depths. Species may occupy the surface of muddy or sandy habitats or dwell up to about one meter deep in the sediment. Kinorhyncha may represent 1–8% of the meiofauna at a given locality and in extreme cases 0.1% or 15–33%.
Whereas species with more original characters use both their head spinoscalids and their trunk for a caterpillar-like forward movement, species with more advanced characters use mainly their head spinoscalids for moving around. Kinorhynchs feed on detritus, bacteria, algae, or diatoms.
The species develop via a series of possibly six juvenile stages to the adult. The adult life history stage can moult at least once in species of a range of genera. The different adult stages may agree or disagree in their morphology. Several studies revealed considerable variation for species of several genera within populations of a sample from a single or from various locations. These more recent findings complicate identification of kinorhynchs and description of new species. It can be expected that a range of species will have to be synonymized, if a larger number of specimens will have been studied in more details.
Currently, the World Kinorhyncha Database contains 348 accepted species names, the species number of all accepted and synonymized species is 591, and 669 taxonomic names of all ranks including synonyms contribute or have contributed to the classification of Kinorhyncha as a whole. The number of accepted species includes two fossil species, five taxa inquirenda and 50 species described from juvenile stages, which are usually considered as nomina dubia.
No guarantee for the correctness of the data can be given. Please inform the editor of any omissions, errors, or typos you come across, or if you need to confirm some crucial data. If you disagree with a synonym or other taxonomic decision, please send in your reasoned argument to the editor. Each contribution will be evaluated and corrections will be incorporated as quickly as possible.
Specimens
Type and non-type specimens of Kinorhyncha were and are mainly deposited in the following museum collections:
- Museum of Natural History, Smithsonian Institution, Washington D.C., USA (USNM; search colection: https://collections.nmnh.si.edu/search/iz/). The museum houses also a Microsoft Access database of the stations of its former curator R. P. Higgins, which is complementary to the museum's catalogued and uncatalogued kinorhynch specimens. Field numbers by Higgins start with RH-...
- Zoological Museum, now The Natural History Museum of Denmark, Copenhagen, Denmark (ZMUC-KIN, NHMD; search collection: http://www.daim.snm.ku.dk/The-digitized-type-collection)
- Zoologisches Museum Berlin, now Museum für Naturkunde Berlin, Germany (ZMB, MNB; search collection: http://zmb.sesam.senckenberg.de/page/index.htm).
Citation
Usage of data from the World Kinorhyncha Database in scientific publications should be acknowledged by citing as follows:- Neuhaus, B. (2025). World Kinorhyncha Database. Accessed at https://www.marinespecies.org/kinorhyncha on 2025-03-20. doi:10.14284/457
Individual pages are individually authored and dated. These can be cited separately: the proper citation is provided at the bottom of each page.
References
This reference list is grouped in order to facilitate quick access to specific topics about Kinorhyncha.
Historical and current classification
This site provides the classification systems of Kinorhyncha published from 1907 until today.|
Class |
Order |
Suborder |
Family |
|
Genus |
|
Echinodera |
Homalorhagae |
|
Pycnophyidae |
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Pycnophyes |
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Trachydemidae |
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Trachydemus |
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larval genera |
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Hyalophyes |
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Centrophyes |
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Leptodemus |
|
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Conchorhagae |
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Pentacontidae |
|
Semnoderes |
|
|
Cyclorhagae |
Nomosomata |
Echinoderidae |
|
Echinoderes |
|
|
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|
|
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Echinoderella |
|
|
|
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|
larval genera |
Habroderes |
|
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Habroderella |
|
|
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Centropsis |
|
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Hapaloderes |
|
|
|
|
Centroderidae |
|
Centroderes |
|
|
|
Xenosomata |
Mesitoderidae |
|
Campyloderes |
|
Order |
Suborder |
Tribus |
Family |
|
Genus |
|
Echinodera |
Cyclorhagae |
Nomosomata |
Echinoderidae |
|
Echinoderes |
|
|
|
|
|
|
Echinoderella |
|
|
|
|
|
larval genera |
Habroderes |
|
|
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Habroderella |
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Centroderidae |
|
Centroderes |
|
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|
larval genera |
Centropsis |
|
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|
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Hapaloderes |
|
|
|
Xenosomata |
Mesitoderidae |
|
Campyloderes |
|
|
Conchorhagae |
|
Pentacontidae |
|
Semnoderes |
|
|
Homalorhagae |
|
Trachydemidae |
|
Trachydemus |
|
|
|
|
|
larval genus |
Leptodemus |
|
|
|
|
Pycnophyidae |
|
Pycnophyes |
|
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|
|
larval genus |
Hyalophyes |
|
|
|
larval genus |
|
|
Centrophyes |
|
Class |
Order |
Suborder |
Tribus |
Family |
Genus |
|
Kinorhyncha |
Echinodera |
Cyclorhagae |
Nomosomata |
Echinoderidae |
Echinoderes |
|
|
|
|
|
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Echinoderella |
|
|
|
|
|
Centroderidae |
Centroderes |
|
|
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|
larval genera |
Centropsis |
|
|
|
|
|
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Hapaloderes |
|
|
|
|
|
|
Habroderes |
|
|
|
|
|
|
Habroderella |
|
|
|
|
Xenosomata |
Campyloderidae (Mesitoderidae) |
Campyloderes |
|
|
|
Conchorhagae |
|
Semnoderidae (Pentacontidae) |
Semnoderes |
|
|
|
Homalorhagae |
|
Trachydemidae |
Trachydemus |
|
|
|
|
|
Pycnophyidae |
Pycnophyes |
|
|
|
|
larval genera |
|
Leptodemus |
|
|
|
|
|
|
Centrophyes |
|
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|
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|
|
Hyalophyes |
|
Class |
Order |
Suborder |
Tribus |
Family |
Genus |
|
Kinorhyncha (= Echinodera = Echinocephala) |
Kinorhyncha |
Cyclorhagae |
Nomosomata |
Echinoderidae |
Echinoderes |
|
|
|
|
|
|
Echinoderella |
|
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|
|
Centroderidae |
Centroderes |
|
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|
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Xenosomata |
Mesitoderidae (= Campyloderidae) |
Campyloderes |
|
|
|
|
larval genera Cyclorhagae |
|
Habroderes |
|
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Habroderella |
|
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Centropsis |
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Hapaloderes |
|
|
|
Conchorhagae |
|
Semnoderidae (Pentacontidae) |
Semnoderes |
|
|
|
Homalorhagae |
|
Pycnophyidae |
Pycnophyes |
|
|
|
|
|
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Trachydemus |
|
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|
|
larval genera Homalorhagae |
|
Hyalophyes |
|
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|
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|
Centrophyes |
|
|
|
|
|
|
Leptodemus |
|
Order |
Suborder |
Tribus |
Family |
Genus |
|
|
Echinodera |
Homalorhagae |
|
Pycnophyidae |
Pycnophyes |
|
|
|
|
|
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Trachydemus |
|
|
|
Heterorhagae |
Conchorhagata |
Semnoderidae |
Semnoderes |
|
|
|
|
Cyclorhagata |
Echinoderidae |
Echinoderes |
|
|
|
|
|
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Echinoderella |
|
|
|
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|
Centroderidae |
Campyloderes |
|
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Centroderes |
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|
Phylum |
Class |
Order |
Family |
Genus |
|
|
Kinorhyncha |
Homalorhagea |
Homalorhagida |
Pycnophyidae |
Pycnophyes |
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Trachydemidae |
Trachydemus |
|
|
|
|
|
|
Hyalophyes |
larval genus |
|
|
|
|
|
Centrophyes |
larval genus |
|
|
|
|
|
Leptodemus |
larval genus |
|
|
Conchorhagea |
Conchorhagida |
Semnoderidae |
Semnoderes |
|
|
|
|
|
Cateriidae |
Cateria |
|
|
|
Cyclorhagea |
Nomosomatida |
Echinoderidae |
Echinoderes |
|
|
|
|
|
|
Echinoderella |
|
|
|
|
|
|
Habroderes |
larval genus |
|
|
|
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Habroderella |
larval genus |
|
|
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Centropsis |
larval genus |
|
|
|
|
|
Haploderes [sic!] |
larval genus |
|
|
|
Xenosomatida |
Campyloderidae |
Campyloderes |
|
|
Phylum |
Order |
Suborder |
Family |
Genus |
|
|
Kinorhyncha |
Cyclorhagida |
Cyclorhagae |
Echinoderidae |
Echinoderes |
|
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|
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Dracoderidae |
Dracoderes |
|
|
|
|
|
Centroderidae |
Centroderes |
|
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|
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Campyloderes |
|
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|
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Condyloderes |
|
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Zekinkaderidae |
Zelinkaderes |
|
|
|
|
Conchorhagae |
Semnoderidae |
Semnoderes |
|
|
|
|
|
|
Sphenoderes |
|
|
|
|
Cryptorhagae |
Cateriidae |
Cateria |
|
|
|
Homalorhagida |
Homalorhagae |
Neocentrophyidae |
Neocentrophyes |
|
|
|
|
|
|
Paracentrophyes |
|
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|
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|
Pycnophyidae |
Pycnophyes |
|
|
|
|
|
|
Kinorhynchus |
|
|
Class |
Order |
Suborder |
Family |
Genus |
|
|
Kinorhyncha |
Cyclorhagida |
Protorhagae |
Antigomonidae [sic!] |
Antigomonas [sic!] |
|
|
|
|
|
Zekinkaderidae |
Zelinkaderes |
|
|
|
|
Cryptorhagae |
Cateriidae |
Cateria |
|
|
|
|
Conchorhagae |
Semnoderidae |
Semnoderes |
|
|
|
|
|
|
Sphenoderes |
|
|
|
|
Cyclorhagae |
Cephalorhynchidae |
Cephalorhyncha |
|
|
|
|
|
Centroderidae |
Centroderes |
|
|
|
|
|
|
Campyloderes |
|
|
|
|
|
|
Condyloderes |
|
|
|
|
|
Dracoderidae |
Dracoderes |
|
|
|
|
|
Echinoderidae |
Echinoderes |
|
|
|
Homalorhagida |
Homalorhagae |
Neocentrophyidae |
Neocentrophyes |
|
|
|
|
|
|
Paracentrophyes |
|
|
|
|
|
Pycnophyidae |
Kinorhynchus |
|
|
|
|
|
|
Pycnophyes |
|
|
Phylum |
Order |
Family |
Genus |
|
|
|
Kinorhyncha |
Cyclorhagida |
Antygomonidae |
Antygomonas |
|
|
|
|
|
Cateriidae |
Cateria |
|
|
|
|
|
Centroderidae |
Campyloderes |
|
|
|
|
|
|
Centroderes |
|
|
|
|
|
|
Condyloderes |
|
|
|
|
|
Echinoderidae |
Cephalorhyncha |
|
|
|
|
|
|
Echinoderes |
|
|
|
|
|
|
Fissuroderes |
|
|
|
|
|
|
Meristoderes |
|
|
|
|
|
|
Polacanthoderes |
|
|
|
|
|
Dracoderidae |
Dracoderes |
|
|
|
|
|
Semnoderidae |
Semnoderes |
|
|
|
|
|
|
Sphenoderes |
|
|
|
|
|
Zelinkaderidae |
Triodontoderes |
|
|
|
|
|
|
Zelinkaderes |
|
|
|
|
Homalorhagida |
Neocentrophyidae |
Neocentrophyes |
|
|
|
|
|
|
Paracentrophyes |
|
|
|
|
|
Pycnophyidae |
Kinorhynchus |
|
|
|
|
|
|
Pycnophyes |
|
|
|
|
|
unplaced family |
Franciscideres |
|
|
|
|
|
|
Tubulideres |
|
|
|
|
|
|
Wollunquaderes |
|
|
|
Sørensen et al. 2015, Sánchez et al. 2016, Yamasaki 2016, 2019, Adrianov & Maiorova 2018 |
|||||
|
Phylum |
Class |
Order |
Family |
Genus |
|
|
Kinorhyncha |
Allomalorhagida |
|
Dracoderidae |
Dracoderes |
|
|
|
|
|
Franciscideridae |
Franciscideres |
|
|
|
|
|
|
Gracilideres |
|
|
|
|
|
Pycnophyidae |
Cristaphyes |
|
|
|
|
|
|
Fujuriphyes |
|
|
|
|
|
|
Higginsium |
|
|
|
|
|
|
Krakenella |
|
|
|
|
|
|
Leiocanthus |
|
|
|
|
|
|
Pycnophyes |
|
|
|
|
|
|
Setaphyes |
|
|
|
|
|
Neocentrophyidae |
Mixtophyes |
|
|
|
|
|
|
Neocentrophyes |
|
|
|
|
|
|
Paracentrophyes |
|
|
|
Cyclorhagida |
Echinorhagata |
Echinoderidae |
Cephalorhyncha |
|
|
|
|
|
|
Echinoderes |
|
|
|
|
|
|
Fissuroderes |
|
|
|
|
|
|
Meristoderes |
|
|
|
|
|
|
Polacanthoderes |
|
|
|
|
Kentrorhagata |
Antygomonidae |
Antygomonas |
|
|
|
|
|
Cateriidae |
Cateria |
|
|
|
|
|
Centroderidae |
Centroderes |
|
|
|
|
|
|
Condyloderes |
|
|
|
|
|
Semnoderidae |
Parasemnoderes |
|
|
|
|
|
|
Semnoderes |
|
|
|
|
|
|
Sphenoderes |
|
|
|
|
|
Zelinkaderidae |
Triodontoderes |
|
|
|
|
|
|
Zelinkaderes |
|
|
|
|
|
incertae sedis |
Tubulideres |
|
|
|
|
|
|
Wollunquaderes |
|
|
|
|
Xenosomata |
Campyloderidae |
Campyloderes |
|
|
|
|
|
|
Ryuguderes |
|
|
Phylum |
Class |
Order |
Family |
Genus |
|
|
Kinorhyncha |
Allomalorhagida |
Anomoirhaga |
Cateriidae |
Cateria |
|
|
|
|
|
Dracoderidae |
Dracoderes |
|
|
|
|
|
Franciscideridae |
Franciscideres |
|
|
|
|
|
|
Gracilideres |
|
|
|
|
|
Neocentrophyidae |
Mixtophyes |
|
|
|
|
|
|
Neocentrophyes |
|
|
|
|
|
|
Paracentrophyes |
|
|
|
|
incertae sedis |
Pycnophyidae |
Cristaphyes |
|
|
|
|
|
|
Fujuriphyes |
|
|
|
|
|
|
Higginsium |
|
|
|
|
|
|
Krakenella |
|
|
|
|
|
|
Leiocanthus |
|
|
|
|
|
|
Pycnophyes |
|
|
|
|
|
|
Setaphyes |
|
|
|
Cyclorhagida |
Echinorhagata |
Echinoderidae |
Cephalorhyncha |
|
|
|
|
|
|
Echinoderes |
|
|
|
|
|
|
Fissuroderes |
|
|
|
|
|
|
Meristoderes |
|
|
|
|
|
|
Polacanthoderes |
|
|
|
|
Kentrorhagata |
Centroderidae |
Centroderes |
|
|
|
|
|
|
Condyloderes |
|
|
|
|
|
Semnoderidae |
Antygomonas |
|
|
|
|
|
|
Parasemnoderes |
|
|
|
|
|
|
Semnoderes |
|
|
|
|
|
|
Sphenoderes |
|
|
|
|
|
Zelinkaderidae |
Triodontoderes |
|
|
|
|
|
|
Zelinkaderes |
|
|
|
|
|
incertae sedis |
Tubulideres |
|
|
|
|
|
incertae sedis |
Wollunquaderes |
|
|
|
|
Xenosomata |
Campyloderidae |
Campyloderes |
|
|
|
|
|
|
Ryuguderes |
|