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 Janstockia clavelinae sp. nov. ( Figs. 415 , 416 ) Typematerial . Holotype (intact , MNHN-IU-2014- 21441 ) anddissectedparatype ( , figured) from Clavelina fecunda (Sluiter, 1904) , AURACEA 1995, south of Matemo, Ibo, Mozambique , depth 15 m , Monniot coll., 17 November 1995 . Etymology . The new species is named after Clavelina , the generic name of the type host. Descriptionoffemale . Body ( Fig. 415A ) vermiform, elongate, cylindrical; consistingof cephalosome, long metasome and short abdomen; body length 6.65 mm. Cephalosome ( Fig. 415B, C ) defined but not articulated from metasome; width 0.66 mm, length 0.47 mm, with paired expanded ventral folds covered with ornamentation of minutesetules. Metasomewithweaklateralconstriction between first pedigerous somite and remaining part ( Fig. 415B ): distances between 4 leg pairs 0.32, 1.14, and 2.42 mm, respectively and distance from leg 4 to posterior margin of abdomen 2.21 mm. Fifth pedigerous and genital somites incorporated into metasome; copulatory pore present on posteroventral surface ( Fig. 415E ). Abdomen ( Fig. 415D ) 157×173 μm, unsegmented, bilobed posteriorly, defined from metasome by dorsal suture line, but lacking any suture line ventrally ( Fig. 415E ). Caudal rami not defined; 6 small caudal setae present on apex of each posterior margin lobe ( Fig. 415E ). Rostrum ( Fig. 415F ) small and tapering, with narrower apical part. Antennule ( Fig. 415G ) strongly tapering, indistinctly 3-segmented, ornamented with setules on first and second segments; first segment longer than remaining part; armature formula 0, 2+aesthetasc, and 9+2 aesthetascs. Antenna ( Fig. 416A ) stout, 3- segmented; first segment (coxa) very broad and short, unarmed; secondsegment (basis) widerthan long, unarmed; terminal segment (endopod) produced into distal claw, armed with 4 small setae near middle. Labrum ( Fig. 415H ) small, semicircular. Mandible ( Fig. 416B ) as elongate lobe bearing 3 setae distally. Maxillule ( Fig. 416C ) broad, distally bilobed, and armed with 5 broad, plumose setae (1 on narrow outer lobe and 4 on broad inner lobe). Maxilla absent. Maxilliped (third mouthpart) ( Fig. 416D ) 2-segmented, unarmed, covered with setules; proximal segment tapering; distal segment with tapering distal tip. Legs 1–4 wider than long, biramous with obscurely segmented protopods and unsegmented rami; coxa unarmed, but basis with pinnate outer seta. Leg 1 ( Fig. 416E ) with patches of fine spinules on ventral surface of coxa and inner ventrodistal surface of basis; exopod with claw-like process and 8 small setae; endopod smaller than exopodwith 6 smallsetae. Leg 2 ( Fig. 416F ) withrow of fine spinules on ventral surface of coxa; basis smooth; exopod with strong, claw-like process and 8 small setae; endopod with 9 small setae. Leg 3 shaped and armed as in leg 2. Leg 4 also shaped as leg 2, except bearing 7 setae on both rami. Leg 5 ( Fig. 415E ) represented by pair of small setae on ventral surface of metasome. Male . Unknown. Remarks . Two species are currently known in the genus Janstockia : J . phallusiella from the Suez Canal and Red Sea ( Boxshall & Marchenkov, 2005 ; Kim I.H. et al ., 2016), and J . truncata Kim I.H. & Moon, 2011 from Korea (Kim I.H. & Moon, 2011). In these two species, the trunk bears a pair of lateral wing-like expansions on the first pedigerous somite (such wing-like expansions are absentin J . clavelinae sp. nov . ), the basis of leg 1 bears a broad inner distal seta which is absent in J . clavelinae sp. nov . , the mandible is armed with 7 setae compared with 3 setae in J . clavelinae sp. nov . , the maxillule is armed with 6 or 7 setae (cf. 5 setaein J . clavelinae sp. nov . ) and some of these setae expanded and globular (cf. all setae attenuated in J . clavelinae sp. nov . ). These differences allow J . clavelinae sp. nov . to be readily differentiated from its two congeners.