Cutler, Edward B; Cutler, Norma J. (1985). A revision of the genera Phascolion Théel, and Onchnesoma Koren and Danielssen (Sipuncula). Proceedings of the Biological Society of Washington. 98(4): 809-850.
Cutler, Edward B; Cutler, Norma J.
A revision of the genera Phascolion Thï¿½el, and Onchnesoma Koren and Danielssen (Sipuncula)
Proceedings of the Biological Society of Washington
The two closely related sipunculan genera, Phascolion and Onchnesoma are reviewed and the species reevaluated in light of a critical examination of historically used morphological characters. Wherever possible, type-material was examined and the accuracy of original descriptions verified. Of the 52 putative species in Phascolion, 23 species and two subspecies are retained as valid and are arranged into five subgenera (two new ones: Villiophora and Isomya). The four Onchnesoma species and one subspecies are retained but one new subspecies is added. The known distribution of each species is given and a brief zoogeographical analysis is offered. Keys to all the species are included.