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 Notopterophorus micropterus Sars G. O., 1921 ( Figs. 88–91 ) Material examined . 8 ♀♀ , 2 ♂♂ (MNHN-IU-2018-1814) from Ascidia mentula M̹ller, 1776, Bergen, Norway ; 63 ♀♀ , 1 ♂ (MNHN-IU-2018-1815) and dissected 2 ♀♀ , 1 ♂from A . mentula , Bergen , Norway . Supplementary description of female . Body ( Fig. 88A ) dark brown in colour after alcohol preservation. Body length 5.40 mm. Prosome ( Fig. 88B ) with somites definedfromeachotherbyweakconstrictions.Firsttothird pedigerous somites each with paired dorsal extensions; small on first pedigerous somite, short, broad and with pointed apex on second, and tapering and with slender apical process on third. Brood pouch oval in dorsal view, with conical process on posteromedial margin (process variable in size, pointed or blunt, sometimes absent). Urosome 6-segmented, but fifth pedigerous somitelargely incorporated into brood pouch. Genital somite 408×476 μm; 4 freeabdominalsomites 497×415, 401×340, 258×252, and 17×190 μm, respectively. Anal somite ( Fig. 88C ) highly sclerotized ventrally and ornamented with rows of minute spinules. Caudal ramus ( Fig. 88C ) about 2.4 timeslongerthan wide, graduallynarrowing distally, armed with 4 claws and 2 setae; claws 36, 29, 25, and 22 μm long; 2 setae located at 60% and 74% of ramus length; ornamented with patch of minute spinules near proximal seta. Rostrum ( Fig. 88D ) small, conical, 67×47 μm, with slightly convex lateral margins each with row of minute spinules. Antennule ( Fig. 88E ) 9-segmented; first and second segments expanded; armature formula 3, 16, 2, 4+aesthetasc, 5, 3+aesthetasc, 2, 2+aesthetasc, and 7+aesthetasc; second segment with minutely wrinkled surface near articulationwith third segment.Antenna ( Fig. 88F ) consisting of coxa, allobasis and free 1-segmented endopod; coxa unarmed; allobasis with 1 small seta and short trace of suture at region slightly proximal to midlength; free compound endopodal segment 2.25 times longerthan wide (90×40 μm), shorter than basis, and armed with 8 small setae plus terminal claw, as long as segment. Labrum ( Fig. 88G ) with 3 setulose lobes along distal margin. Mandible ( Fig. 88H ) with 5 teeth along medial margin of coxal gnathobase, middle tooth smaller than other 4; basiswith 1 medial seta; exopodwith 5 setae, outermost seta longer than others; endopod with 4 and 10 setaeonfirstandsecond segments, respectively; outermost and fifth outer setaon distal margin of second segment distinctly longerthan others on segment. Paragnath ( Fig. 88I ) with 2 pointed processes (1 apical and 1 subapical) and setulose medial margin. Maxillule ( Fig. 88J ) armed with 10 setae on arthrite, 1 on coxal endite, 2 on epipodite; basis with 4 setae on medial margin, 2 middle setae larger than other 2; exopod with 4 setae distally; endopod 2 segmentedwith 4 and 3 setae onfirst and second segments, respectively. Maxilla ( Fig. 89A ) 5-segmented; syncoxa subdivided by incomplete unsclerotized region, with 4, 1, 2, and 3 setae on first to fourth endites, respectively; basis with 2 setae and 1 slender claw bearing 2 or 3 pairs of spinules on concave margin; endopod slender, armed with 1, 1, and 4 setae on first to third segments, respectively. Maxilliped ( Fig. 89B ) 3-segmented, but first and second segmentsseparatedbyincomplete articulation; armedwith 9, 1, and 4 setae on first to third segments, respectively; first segment ornamented with rows of minute spinules on anterior and posterior surfaces; third segment with faint, incomplete suture line. Legs 1–4 ( Fig. 89 C–F) each with 3-segmented exopod and 2-segmented endopod; exopods slightly longer than endopods. Inner seta on coxa well-developed in legs 1 and 2, but lacking in legs 3 and 4. Outer seta on basis small in all legs. Inner distal seta on basis of leg 1 slender, smooth, and longer than first endopodal segment. Distalmost spine on third exopodal segment of leg 2 distinctly longer than other spines on same segment, but same element on legs 3 and 4 shorter than other spines on segment. Second endopodal segment of leg 3 with trace of articulation at proximal third ( Fig. 89E ). Armature formula for legs 1–4 as follows: FIGURE 88. Notopterophorus micropterus Sars G. O., 1921 , female. A, habitus, right; B, habitus, dorsal; C, distal part of abdomen, right; D, rostrum; E, antennule; F, antenna; G, labrum; H, mandible; I, paragnath; J, maxillule. Scale bars: A, B, 0.5 mm; C, E–J, 0.05 mm; D, 0.02 mm. FIGURE 89. Notopterophorus micropterus Sars G. O., 1921 , female. A, maxilla; B, maxilliped; C, leg 1; D, leg 2; E, leg 3; F, leg 4; G, leg 5. Scale bars: A, B, G, 0.05 mm; C–F, 0.1 mm. FIGURE 90. Notopterophorus micropterus Sars G. O., 1921 , male. A, habitus, right; B, antennule; C, antenna; D, mandible; E, maxillule; F, maxilliped; G, leg 2. Scale bars: A, 0.1 mm; B–G, 0.02 mm. FIGURE 91. Notopterophorus micropterus Sars G. O., 1921 , male. A, leg 3; B, leg 4. Scale bars: 0.02 mm.
Coxa Basis Exopod Endopod
Leg 1 0-1 1-I I-1; I-1; III , I, 4 0-1; 1, 2, 4
Leg 2 0-1 1-0 I-1; I-0; III , I, 0 0-1; 1, 2, 5
Leg 3 0-0 1-0 I-1; I-0; III , I, 0 0-1; 1, 2, 5
Leg 4 0-0 1-0 I-0; I-0; III , I, 0 0-1; 1, 2, 4
Leg 5 ( Fig. 89G ) consisting of protopod and exopod. Protopod not articulated from somite, with 1 naked seta on outer distal process and row of spinules at ventrodistal region near base of exopod. Free exopodal segment 3.6 timeslongerthan wide (138×38 μm), slightly narrowing distally, armed with 1 small spine and 1 slender seta; ornamented with 5 rows of minute spinules on medial surface and 1 or 2 rows of minute spinules on outer surface. Supplementarydescriptionofmale . Body ( Fig. 90A ) distinctly segmented. Bodylength 1.58 mm. Prosome-urosome division indistinct. Prosome slightly dorsoventrally depressed. Urosome 6-segmented, cylindrical, curved ventrally. Anal somite with fewer spinules on ventral surface than in female. Caudal rami as in female. Rostrum as in female. Antennule ( Fig. 90B ) 9- segmented but articulation indistinct between penultimate and terminal segments; non-geniculate; armature formula 3, 12+ III , 4, 4+aesthetasc. 5. 3+aesthetasc, 2, 2, and 7+aesthetasc; secondsegment armed with 12 setae and 3 conical, thick spines. Antenna ( Fig. 90C ) much stouter than that of female; free endopodal segment as long as wide, armed with 8 setae plus terminal claw, longerthan segment. Labrum as in female. Mandible ( Fig. 90D ) with 5 equal teeth on coxal gnathobase; basis with large, globular outer proximal swelling; 5 setae on exopod equal in length; endopod with 2 and 8 setaeonfirst and second segments, respectively. Maxillule ( Fig. 90E ) different from that of female in having 2 setae on first endopodal segment; second proximal seta on basis larger than other 3 setae. Maxilla as in female. Maxilliped ( Fig. 90F ) with 7 (3+4) setaeonfirst segment. Leg 1 asin female. Legs 2–4 ( Figs. 90G , 91A, B ) with rami broader and shorter than in female; terminal spine on third exopodal segment of each leg much longer than other spines. Distal endopodal segment of legs 2 and 3 armed with 3 spines and 5 setae. Distal endopodal segment leg 4 armed with 4 spines and 3 setae. Armature formula for legs 2–4 as follows: FIGURE 92. Habitus of three species of Notopterophorus . A, female N . auritus ( Thorell, 1859 ) , right; B, C, female N . elongatus Buchholz, 1869 , right and dorsal; D, E, female N . papilio Hesse, 1864 , right and ventral. Scale bars: 0.5 mm.
Leg 2 0-1 1-0 I-1; I-0; III , I, 4 0-1; I, II , 5
Leg 3 0-0 1-0 I-1; I-0; III , I, 3 0-1; I, II , 5
Leg 4 0-0 1-0 I-0; I-0; III , I, 2 0-1; I, III , 3
Leg 5 with 2 rows of minute spinules on medial surface, otherwise similartothatof female. Leg 6 represented by 2 naked setae on genital operculum. Remarks . It is uncertain whether N . micropterus is a distinct species or merely a form of N . auritus . Our female specimens possess short wing-like extensions on the first to third pedigerous somites, as figured by Sars (1921) , and on this evidence we tentatively identify them as N . micropterus . However, as stated above, this whole cluster of species is in urgent need of revision to determine the validity of the nominal species.