Belongs within: Eumetazoa.
Contains: Sipunculida.
The Sipuncula, peanut worms, are a group of marine worms with a retractile proboscis (Howell 1962). Though often treated as a distinct ‘phylum’ within the animals, recent analyses have suggested that they may be derived annelids that have secondarily lost segmentation.
Characters (from Howell 1962): Body unsegmented or poorly segmented, cylindrical or subcylindrical; retractile introvert present at anterior end, may be armed with chitinous hooks.
<==Sipuncula [Sipunculoidea] |--Archaeogolfingia caudataEL11, C12 `--+--Cambrosipunculus tentaculatusPE16, C12 `--+--SipunculidaGD00 `--PhascolosomidaGD00 |--Aspidosiphonidae [Aspidosiphoniformes]CG85 | |--Cloeosiphon aspergillus (Quatrefages 1865)CG85, RP07 | `--+--LithacrosiphonCG85 | `--AspidosiphonCG85 | |--A. albus Murina 1967E86 | |--A. clavatusM62 | |--A. elegansMA10 | |--A. exiguus Edmonds 1974E86 | |--A. laevis Quatrefages 1865BS17 | |--A. misakiensisGD00 | |--A. muelleriMS98 | |--A. spinalisE86 | |--A. tenuis Sluiter 1886FP15 | `--A. zinniE86 `--Phascolosomatidae [Phascolosomaformes]CG85 |--ApionsomaCG85 | |--A. misakianumPH06 | `--A. murinae (Cutler 1969)MA10 `--+--Antillesoma antillarum (Grube & Öersted 1858)CG85, RP07 `--PhascolosomaCG85 |--P. agassiziiMA10 |--P. antillarumCH97 |--P. arcuatum (Gray 1828)BS17 |--P. australeHa15 |--P. eremitaHa15 |--P. granulatumZHT01 |--P. japonicaKBC03 |--P. margaritaceumO01 |--P. nigrescens (Keferstein 1865)BS17 |--P. pellucidumHa15 |--P. saprophagicumMA10 `--P. turneraeMA10 Sipuncula incertae sedis: Epitrachys Ehlers 1869H62 `--*E. rugosus Ehlers 1869H62 Lecathylus Weller 1925H62 `--*L. gregarius Weller 1925H62 Schizoproboscina Yakovlev 1939H62 `--*S. ivanovi Yakovlev 1939H62 Stoma Hadding 1913H62 `--*S. hians Hadding 1913H62 ‘Protholothuria’ annulataFE66 Physcosoma granulatumPP64 DendrostomaA99 |--D. dehamataHe15 `--D. pyroidesA99
*Type species of generic name indicated
References
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