Homalorhagida

Pycnophyes calmani, from here.

Belongs within: Ecdysozoa.

The Homalorhagida are a group of marine kinorhynchs distinguished by their triangular cross-section.

Characters (from Higgins 1986): 6-8 neck plates; distinctly triangular in cross-section; spines reduced.

Homalorhagida [Homalorhagae]
    |--Neocentrophyes Higgins 1969 [Neocentrophyidae] H86
    |    |--N. intermedius Higgins 1969 H86
    |    `--N. satyai Higgins 1969 H86
    `--Pycnophyidae H86
         |--Kinorhynchus Sheremetevskij 1974 H86
         |    |--K. anomalus Lang 1953 H86
         |    |--K. apotomus Higgins 1983 H86
         |    |--K. belizensis Higgins 1983 H86
         |    |--K. cataphractus Higgins 1961 H86
         |    |--K. deirophorus Higgins 1983 H86
         |    |--K. distentus Higgins 1983 H86
         |    |--K. erismatus Higgins 1983 H86
         |    |--K. fimbriatus Higgins 1982 H86
         |    |--K. giganteus (Zelinka 1908) H86
         |    |--K. ilyocryptus Higgins 1961 H86
         |    |--K. langi (Higgins 1964) H86
         |    |--K. mainensis (Blake 1930) H86
         |    |--K. paraneapolitanus Sheremetevskij 1974 H86
         |    |--K. phyllotropis Brown & Higgins 1983 H86
         |    |--K. spinosus (Lang 1949) H86
         |    |--K. stenopygus Higgins 1983 H86
         |    `--K. trisetosus Higgins 1983 H86
         `--Pycnophyes Zelinka 1907 H86
              |--P. beaufortensis Higins 1964 H86
              |--P. calmani Southern 1914 H86
              |--P. carinatus Zelinka 1928 H86
              |--P. chiliensis Lang 1953 H86
              |--P. communis Zelinka 1908 H86
              |--P. corrugatus Higgins 1983 H86
              |--P. dentatus (Reinhard 1881) H86
              |--P. echinoderoides Zelinka 1928 H86
              |--P. ecphantor Higgins 1983 H86
              |--P. egyptensis Higgins 1966 H86
              |--P. emarginatus Higgins 1983 H86
              |--P. flagellatus H86
              |--P. flaveolatus Zelinka 1928 H86
              |--P. frequens Blake 1930 H86
              |--P. iniorhaptus Higins 1983 H86
              |--P. kielensis Zelinka 1928 H86
              |--P. longicornis Higgins 1983 H86
              |--P. maximus Reimer 1963 H86
              |--P. odhneri Lang 1953 H86
              |--P. ponticus (Reinhard 1881) H86
              |--P. robustus Zelinka 1928 H86
              |--P. rugosus Zelinka 1928 H86
              |--P. sanjuanensis Higgins 1961 H86
              |--P. sculptus Lang 1949 H86
              `--P. zelinkaei Southern 1914 H86

*Type species of generic name indicated

REFERENCES

[H86] Higgins, R. P. 1986. Kinorhyncha. In Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) (L. Botosaneanu, ed.) pp. 110-118. E. J. Brill / Dr. W. Backhuys: Leiden.