Biology:Kalyptorhynchia

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Short description: Suborder of rhabdocoel flatworms

Kalyptorhynchia
Gyratrix hermaphroditus.jpg
Gyratrix hermaphroditus.
Scientific classification e
Domain: Eukaryota
Kingdom: Animalia
Phylum: Platyhelminthes
Order: Rhabdocoela
Suborder: Kalyptorhynchia
Graff, 1905
Infraorders
  • Eukalyptorhynchia
  • Schizorhynchia

Kalyptorhynchia is a suborder of rhabdocoel flatworms. It contains almost 600 species and has a cosmopolitan distribution.[1]

Description

All kalyptorhynchs have an anterior muscular proboscis which is used to capture prey. The proboscis is located inside an invagination of the epidermis called the proboscis-sheath that is closed by a sphincter at the tip of the body.[1] Another synapomorphy supporting the group is the incorporation of the axonemes within the cell body of sperm cells during spermiogenesis.[2]

Classification

Kalyptorhynchs are traditionally classified into two infraorders: Eukalyptorhynchia, with a cone-shaped proboscis, and Schizorhynchia, with a proboscis formed by two opposite parallel muscular sheets.[1] However, molecular studies have shown that Eukalyptorhynchia is not a monophyletic group and further studies are necessary to improve the knowledge about the relationships of the different kalyptorhynch clades.[1][2]

References

  1. 1.0 1.1 1.2 1.3 Smith, Julian P. S., III; Litvaitis, Marian K.; Gobert, Stefan; Uyeno, Theodore; Artois, Tom (2015). "Evolution and Functional Morphology of the Proboscis in Kalyptorhynchia (Platyhelminthes)". Integrative and Comparative Biology 55 (2): 205–216. doi:10.1093/icb/icv056. ISSN 1540-7063. PMID 26002347. 
  2. 2.0 2.1 Willems, Wim R.; Wallberg, Andreas; Jondelius, Ulf; Littlewood, David T. J.; Backeljau, Thierry; Schockaert, Ernest R.; Artois, Tom J. (2006). "Filling a gap in the phylogeny of flatworms: relationships within the Rhabdocoela (Platyhelminthes), inferred from 18S ribosomal DNA sequences". Zoologica Scripta 35 (1): 1–17. doi:10.1111/j.1463-6409.2005.00216.x. ISSN 0300-3256. 

Wikidata ☰ Q5017812 entry