Six new species ofArchimonocelididae Meixner, 1938 (Platyhelminthes, Proseriata) from the Pacific, with proposal of a new genus Author Curini-Galletti, Marco Dipartimento di Medicina Veterinaria, Università di Sassari, Sassari, Italy. Author Schockaert, Ernest R. 0000-0003-0666-5604 Hasselt University, Centre for Environmental Sciences, Research Group Zoology: Biodiversity and Toxicology, Universitaire Campus Gebouw D, B- 3590 Diepenbeek, Belgium. & ernest. schockaert @ uhasselt. be; https: // orcid. org / 0000 - 0003 - 0666 - 5604 ernest.schockaert@uhasselt.be text Zootaxa 2021 2021-04-29 4965 3 515 528 journal article 6995 10.11646/zootaxa.4965.3.6 8e5134e2-7285-4d81-8042-dcd45a53a7f4 1175-5326 4754366 77F0483A-C426-43CC-95F0-322A9052D1AE Tajikacelis macrostomoides n. sp. ( Fig. 1B , 2B , 4A–D , 10B ) Diagnosis. Species of Tajikacelis with a strongly curved stylet, 45–49 μm long (N=3), with a proximal opening of 13–16 μm, narrowing to about 5 μm at around 1/3 of its length and 3–4 μm wide at the distal end, which is truncated. The testes are packed in two rows with 7–8 pairs in front of the ovaries and more than 30 pairs between the level of the ovaries and the basis of the pharynx. Female duct muscular prepenially and widened postpenially; a vagina was not seen. Occurrence . Arrawarra, NSW, Australia in poorly sorted coarse sand in a permanent tide pool among rocks S. of the headland ( 30°03’38.8”S ; 153°12’12.8”E ) ( type locality)( 30 October 1997 by E. R .S). Kirra Beach , Queensland , Australia ( 28°09’58.7”S ; 153°31’58.2”E ), lower intertidal close to rocks, medium-coarse sand ( 30 August 1996 by M.C-G.) . Material studied . Three animals studied alive and mounted, one of which holotype ( QM G238522 ) , the remaining paratypes ( CZM824-825 ) . One animal studied alive and mounted as whole mount from Kirra Beach ( CZM826 ) . Etymology. The specific epithet reflects the similarity between the stylet of the new species and those of many species of Macrostomum Schmidt 1848 (Platyhelminthes, Macrostomida ).