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

Kalyptorhynchia
Gyratrix hermaphroditus.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Platyhelminthes
Order: Rhabdocoela
Suborder: Kalyptorhynchia
Graff, 1905
Infraorders

Description edit

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 edit

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 edit

  1. ^ a b c d 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. PMC 4612338. PMID 26002347.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ a b 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. hdl:1942/1609. ISSN 0300-3256. S2CID 85917387.