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 Doroixys pilosa sp. nov. ( Figs. 324 , 325 ) Typematerial . Holotype (intact ♀ , MNHN-IU-2014- 21374 ) , paratype (intact ♀ , MNHN 0IU-2014-21375), anddissectedparatype ( ♀ , figured) from Eudistoma gilboviride (Sluiter, 1909) (MNHN-IT-2008-4052 = MNHN A3/ EUD /88), CRRFOCDN 0678-U, Rasch Passage, Papua New Guinea ( 05°09.27’S , 145°49.82’E ), depth 3 m , 04 November 1993 . Etymology . The specific name is from the Latin pilos (=hairy) and refers to the dense ornamentation of minute setules covering the body. FIGURE 322. Doroixys obesa sp. nov. , female. A, habitus, right; B, leg 5 and urosome, ventral; C, left caudal ramus, dorsal; D, posterolateral process of cephalic shield; E, rostrum; F, antennule; G, antenna; H, labrum; I, mandible; J, maxillule. Scale bars: A, 0.1 mm; B, D, 0.05 mm; C, E–J, 0.02 mm. FIGURE 323. Doroixys obesa sp. nov. , female. A, maxilla; B, maxilliped; C, leg 1; D, leg 2; E, leg 3; F, leg 4. Scale bars: 0.02 mm. FIGURE 324. Doroixys pilosa sp. nov. , female. A, habitus, right; B, cephalic horn; C, leg 5 and urosome, ventral; D, left caudal ramus, dorsal; E, rostrum; F, antennule; G, antenna; H, labrum; I, mandible; J, maxillule; K, maxilla; L. maxilliped. Scale bars: A, 0.2 mm; B, D–L, 0.02 mm; C, 0.1 mm. FIGURE 325. Doroixys pilosa sp. nov. , female. A, leg 1; B, leg 2; C, leg 3; D, leg 4; E, left and right legs 5. Scale bars: 0.05 mm. Descriptionoffemale . Body ( Fig. 324A ) stout, bearing numerous minutesetules on external surface (ornamentation not shown in Fig. 324A ): body length 1.39 mm. Prosome 1.05 mm long: dorsalcephalic shield bearing prominent, paired dorsally-curved, hornlikeprocesses posterolaterally ( Fig. 324B ). Metasome incompletely 4-segmented; fourth pedigeroussomite swollen, forming brood pouch. Freeurosome ( Fig. 324C ) 5-segmented, graduallynarrowingposteriorly, covered with minute setules: genital and 4 abdominal somites 64×173, 64×156, 49×122, 36×105, and 64×91 μm, respectively. Caudalramus ( Fig. 324D ) tapering, 2.85 times longer than wide (77×27 μm): armed with 6 setae; outer lateral and dorsal setae positioned at 59 and 66% of ramus length, respectively; all setae small, at most half as long as width of ramus at base.
Coxa Basis Exopod Endopod
Leg 10-0 1-I I-1; I-1; I+1, 2, 3 0-1; 0-1; 1, 2, 3
Leg 20-0 1-0 1-0; 1-0; 3, 1, 5 0-0; 0-0; 1, 2, 3
(or 0, 2, 3)
Leg 30-0 1-0 1-0; 1-0 0-0; 0-0; 1, 2, 2
(or 1-1); 3, 1, 5 (or 0, 2, 2)
Leg 40-0 1-0 1-0; 1-0; 3, 1, 4 0-0; 1, 2, 0
Rostrum( Fig.324E )setulose,longerthanwide(98×60 μm), with parallel lateral margins in proximal third, but tapering steeply in distal two-thirds towards angular apex. Antennule ( Fig. 324F ) 147 μmlong, stronglytapering, 8-segmented, but articulation incomplete between last 2 segments: armatureformula 2, 14, 6, 3+aesthetasc, 2, 2+aesthetasc, 4, and 7+aesthetasc; all setae naked. Antenna ( Fig. 324G ) 3-segmented, consistingof unarmed coxa and basis and unsegmented endopod; endopod as long as basis and about 2.6 times longerthan wide (50×19 μm), ornamented with few setules: armed with 5 small setae (arranged as 1, 2, and 2) plus terminal claw slightly less than half length of endopod. Labrum ( Fig. 324H ) bearing broad, convex, setulose posterior margin. Mandible ( Fig. 324I ) with broad coxal gnathobase bearing 5 teeth and 1 seta: basis unarmed, lacking medial seta: exopod short, armedwith 4 large subequal setae and 1 small outer seta (about 25% as long as larger setae): endopod 2-segmented; first segment with 1 broad seta mediodistally; second segment with 5 or 4 setae, smallest outer seta (indicated by arrowhead) present or absent. Maxillule ( Fig. 324J ) armed with 9 setae on arthrite, 1 on epipodite, 1 on basis, 4 on exopod and 3 on endopod; coxal endite absent. Maxilla ( Fig. 324K ) 3-segmentedwith 1-segmented endopod: armed with 4, 2, and 2 setae on first to third endites of syncoxa, respectively, clawplus 1 setaon basis, and 3 setaeon endopod; claw on basis ornamented with minute spinules along distal third of concave margin. Maxilliped ( Fig. 324L ) unsegmented, armedwith 6 setae, and ornamented with 2 transverse rows of spinules on outer surface. Legs 1–3 ( Fig. 325 A-C) with 3-segmented rami. Leg 4 ( Fig. 325D ) with 3-segmented exopod and 2-segmented endopod; compound distal endopodal segment of leg 4 bearing trace of articulation in middle. Inner coxal seta absent in all legs. Inner distal spine on basis of leg 1 small, 15 μm long. Distal seta on third exopodal segment of leg 1 broadened. All setae on rami of legs 2–4 bluntly tipped. Outer seta on third endopodal segment of legs 2 and 3 present or absent. Inner seta on second exopodal segment of leg 4 also present or absent. Leg 5 ( Fig. 325E ) represented by outer protopodal seta on ventrolateral margin of somite plus tapering, pointed inner exopodal process bearing 1 seta subdistally on outer margin. Male . Unknown. Remarks . The setation of the swimming legs and the mandibular endopod are unreliable for characterising Doroixys pilosa sp. nov. due to the variability exhibited between specimens. Instead, this new species exhibits a remarkable autapomorphic feature, the single-segmented endopod of the maxilla. The combination of this feature with the lack of a seta on the mandibular basis and the relative lengths of the setae on the mandibular exopod (small outermost seta and 4 other equally large setae) allows this new species to be separated from all of its congeneric species.