Untold diversity: the astonishing species richness of the Notodelphyidae (Copepoda: Cyclopoida), a family of symbiotic copepods associated with ascidians (Tunicata) Author Kim, Il-Hoi 0000-0002-7332-0043 Korea Institute of Coastal Ecology, Inc., 802 - ho, 302 - dong, 397 Seokcheon-ro, Ojeong-gu, Bucheon, Gyeonggi-do 14449, Republic of Korea ® ihkim @ gwnu. ac. kr; https: // orcid. org / 0000 - 0002 - 7332 - 0043 ihkim@gwnu.ac.kr Author Boxshall, Geoff A. 0000-0002-7332-0043 Korea Institute of Coastal Ecology, Inc., 802 - ho, 302 - dong, 397 Seokcheon-ro, Ojeong-gu, Bucheon, Gyeonggi-do 14449, Republic of Korea ® ihkim @ gwnu. ac. kr; https: // orcid. org / 0000 - 0002 - 7332 - 0043 ihkim@gwnu.ac.kr text Megataxa 2020 2020-12-24 4 1 1 6 http://zoobank.org/3fdd970e-62f1-4f67-8cce-10870bdb3c01 journal article 54097 10.11646/megataxa.4.1.1 7c9bc39d-9910-46f1-9558-c0647b9cbbdb 2703-3090 4591138 Nodoscarus quadrisetatus gen. et sp. nov. ( Fig. 438 ) Type material . Holotype ♀ (dissected and mounted on a slide, MNHN-IU-2014-21461 ) from Leptoclinides robiginis Monniot, F., 1989 , south lagoon , New Caledonia . Etymology . The specific name refers to the presence of four setae on the mandible. Descriptionoffemale . Body ( Fig. 438A ) vermiform, elongate, cylindrical, unsegmented, almost straight, surface densely covered with fine setules (setules not shown in Fig. 438A, B ). Bodylength 6.25 mm; body width 0.93 mm in middle. Paired convoluted ovaries, occupying 70% of body length, visible through body wall. Body tapering slightly anteriorly. Posterior end of body ( Fig. 438B ) bilobed, with shallow median (anal) incision. Rostrum absent ( Fig. 438C ). Antennule ( Fig. 438C ) as broad, semicircular lobe, surface covered with fine setules plus 1 or 2 small setae apically. Antenna ( Fig. 438D ) stout, 3-segmented: coxa short; basis only slightly longerthan wide, unarmed; endopod about 1.4 times longer than wide (24×17 μm): armed with 1 subdistal and 3 small distal setae, plus short, stout terminal claw, half as long as endopod. Labrum not discernible. Only 2 pairs of mouthparts present. Mandible (first pair, Fig. 438E ) lobate, tipped with 4 naked setae. Maxillule (second pair, Fig. 438F ) lobate, tipped with 2 setae. Large, anteriorly-directed, post-oral protuberance present posterior to oral region ( Fig. 438C ). Maxillae, maxillipeds, and legs absent. Male . Unknown. Remarks . Nodoscarus quadrisetatus gen. et sp. nov. is best compared with N . senisetatus gen. et sp. nov. , because both of these two species retain only two pairs of mouthparts and share the presence of 2 setae on the second pair (the maxillules). The new species can be distinguished from N . senisetatus gen. et sp. nov. by the lack of a rostrum and by the possession of 4 setae on the mandible (vs. 6 setaein N . senisetatus gen. etsp. nov. ).