Resolving the Lourinia armata (Claus, 1866) complex with remarks on the monophyletic status of Louriniidae, Monard 1927 (Copepoda: Harpacticoida) Author Karaytuğ, Süphan 0000-0001-8980-4133 Department of Biology, Faculty of Art and Science, Mersin University, Çiftlikköy Campus, Mersin, Turkey. suphankaraytug @ gmail. com; https: // orcid. org / 0000 - 0001 - 8980 - 4133 suphankaraytug@gmail.com Author Sak, Serdar 0000-0002-4955-3162 Department of Biology, Faculty of Science and Literature, Balıkesir University, Çağış Campus, Balıkesir, Turkey. & serdarsak @ gmail. com; https: // orcid. org / 0000 - 0002 - 4955 - 3162 serdarsak@gmail.com Author Alper, Alp 0000-0001-5507-4072 Department of Biology, Faculty of Science and Literature, Balıkesir University, Çağış Campus, Balıkesir, Turkey. & alpalper 80 @ gmail. com; https: // orcid. org / 0000 - 0001 - 5507 - 4072 alpalper80@gmail.com Author Sönmez, Serdar Department of Biology, Faculty of Science and Letters, Adıyaman University, Adıyaman, Turkey. text Zootaxa 2021 2021-10-12 5051 1 346 386 journal article 4038 10.11646/zootaxa.5051.1.15 f4c55cc5-fb40-4343-833d-db7f91e0d93b 1175-5326 5563725 197BF058-FCD8-444B-8749-879FE0534EBD Family Louriniidae Monard, 1927 Ceyloniidae Scott, 1909 , p. 227 . Ceyloniellidae Monard, 1937 p. 83 Amended diagnosis . Copepoda Harpacticoida . Body slender and more or less cylindrical, without prominent distinction between prosome and urosome, first thoracic somite fused to cephalosome. Urosome 5-segmented in female; comprising fifth pedigerous somite, genital double-somite and three free abdominal somites. Genital double-somite longer than wide, subdivided by discontinuous lateral sutures. Paired genital apparatus located ventrally on genital double-somite; copulatory pore located on ventral midline. Anal operculum straight. Urosome 6-segmented in male; comprising fifth pedigerous somite, genital somite and four free abdominal somites. Caudal rami with six setae. Rostrum well developed, with rounded tip, anteroventrally directed. Antennule 7-segmented; third segment longest; fourth segment with aesthetasc fused basally to seta and arising from pedestal. Antennule 9-segmented in male; haplocer. Antenna biramous; with separate coxa; allobasis unarmed; endopod 1-segmented; exopod 1-segmented with two setae. Mandible with well developed coxal gnathobase; palp reduced. Maxillule with well developed praecoxal arthrite; with coxa. Maxilla with two syncoxal endites; allobasis represented by claw. Maxilliped vestigial, represented by tapering process, unsegmented with a seta distally. P1–P4 with 3-segmented exopods and 2-segmented endopods. Male P3 with 3-segmented endopod; second segment with apophysis. Spine and setal formula of P1–P4 as follows:

Exopod	Endopod
P1	0.0.112	1.210
P2	0.1.123	1.321
P3	0.1.123	1.3(2)21[1.apo.2 in ♂]
P4	0.1.123	1.121

P5 confluent; with well developed baseoendopod; exopod separate. Male P5 confluent, exopod fused to baseoendopod.