Bathyphelliidae with well developed base. Column smooth with cinclides in its lower part. Sphincter mesogloeal, weak. Margin fairly distinct, without fosse. Tentacles short, hexamerously arranged, the outer tentacles considerably shorter than the inner ones. Longitudinal muscles of tentacles and radial muscles of oral disc ectodermal. 2 well developed siphonoglyphs. Mesenteries more numerous distally than proximally. Six perfect pairs of mesenteries, (macrocnemes) which have gonads, strong circumscribed retractors, filaments and acontia, microcnemes without these organs. Basilar muscles well developed, also on the stronger imperfect mesenteries. Cnidom: spirocysts, basitrichs, microbasic p-mastigophors.
A. elongatus Carlgren 1924
Definitions and contained taxa are those of Oscar Carlgren as published in 1949 : Kungl Svenska Vetenskapsakadamiens Handlingar, Series 4, Volume 1, Number 1
Electronic version made possible by NSF grant DEB95-21819 in the PEET program to D. G. Fautin.