Plankton Biol. Ecol. 52(I): 33^7. 2005 plankton biology & ecology ''•■ The Plankton Society ofJapan 2(11)5 Three new species of Tharybis (Crustacea: Copepoda: Calanoida: Tharybidae) from benthopelagic waters of the Pacific Ocean Frank D. Ferrari1* & E. L. Markhaseva2 1DepartmentofZoology, MRC-534, NationalMuseum ofNaturalHistory, Smithsonian Institution, 4210SilverHillRti. Suitland, MD20746. U.S.A. 2RussianAcademyofSciences, ZoologicalInstitute; Universitetskayanab. I, 199034. St. Petersburg, Russia Received9April2004; Accepted 17 September2004 Abstract: Three new benthopelagic species of Tharybis are described from two localities in the Pa cific Ocean: T. pseudomegalodactyla near Kona, Hawaii; T. juhlae near Kona, Hawaii, and from Vol cano 7; I sbuheiella from Volcano 7. The new species are distinguished from known species by the shapes ofthe genital complex ofthe female and the segments of the first and fifth leg, and the seta- tion of maxilla 1, maxilla 2 and maxilliped. There are now 25 nominal species of Tharybis. A distally vaulted praecoxal lobe of maxilla 1 is proposed as a synapomorphy for species of Tharybis; other possible synapomorphies are discussed. Key words: Tharybis, new species, Pacific Ocean, morphology, synapomorphies out comment: T. neptuni (Cleve 1905) originally described Introduction as a species of Scolecithricelkv. T. altera (Grice & Hulse- Sars (1902) established the genus Tharybis for T. mann 1970) and T. compacta (Grice & Hulsemann 1970) macwphthalma which was collected with a dredge at 100 both originally described as species ofUndinella. Bradford fathoms in the Christiania Fjord offNorway. Sars noted that et al. (1983), also without comment, suggested moving T. this new genus and species, and its new family did not ex paraincertus (Grice & Hulsemann 1965) and T. macro- hibit genderdimorphism in antenna 1 orthe oral limbs, and cephahn (Grice & Hulsemann 1970) both originally de that a fifth leg is present in females. Sars also noted the scribed as species ofXanihocalamts. Schulz & Beckmann similarity of its maxilla 2 [which Sars called first maxil (1995) moved T. groenlandica which Tupitzky (1982) de liped] to species of Phaennidae, particularly Phaenna, and scribed as a species ofXanthocalanus to Tharybis, and re mentioned that the firstenditic lobe ofmaxilla 1 is large. moved T. paraincertus (Grice & Hulsemann 1965) and T. Since Sars (1902), sixteen calanoid species, often associ macmcephalon (Grice & Hulsemann 1970) from Tharybis. ated with the sea floor, have been described as species of However, Schulz & Beckmann did not state to which genus Tharybis: T. sagamiensis Tanaka, 1960; T. fuitoni Park, T. paraincertus or T. macmcephalon belong, nor did they 1967; T. asymmetrica Andronov, 1976; T. megalodactyla provide synapomorphies for Tharybis. We have chosen to Andronov, 1976; T. minorSchulz, 1981; T. magna Bradford retain both species in Thaiybis at this time. Andronov & Wells, 1983; T. angularis Schulz, 1995 (in Schulz & (2002) placed T. crenata Schulz, 1995 in synonymy with T. Beckmann 1995); T. crenata Schulz, 1995 (in Schulz & groenlandica and T. minor Schulz, 1981 in synonymy with Beckmann 1995); T. inaequalis Bradford-Grieve, 2001; T. T. asymmetrica Andronov, 1976, but without examining inflata Andronov, 2002; T. lauta Andronov, 2002: T. type specimens of the species whose name was syn- macmphthalmoida Andronov, 2002; T. scaura Andronov, onymized. Finally, Ohtsuka et al. (1998) re-described speci 2002; T. tuberosa Andronov, 2002; T. twnidula Andronov, mens of T. magna which differ from the original descrip 2002. Schulz (1981) moved three species to Tharybis with- tion, but without observingthe type specimens. In this paper, we describe three new species of Tharybis and discuss possible synapomorphies for the genus. We *Corresponding author: Frank D. Ferrari; e-mail. Ferrari.Frank@MSC- SI.FDU continue to recognize all ofSchulz's species until a careful 34 F. D. Ferrari& E. L. Markhaseva comparison has been made of the type specimens. With on a segment of antenna 1 are designated 2+1; "?" indi three new species here, there are presently 25 nominal cates that a setal element was broken so that its identity species in thegenus Tharybis. could not be determined and only the scar at the location of attachment ofthe seta was observed. Setules are epicuticu- lar extensions of a seta; denticles are epicuticular exten Materials and Methods sions of an appendage segment; spinules are epicuticular Specimens from Kona, Hawaii, were collected in seavva- extensionsofa somite. ter flowing from a flexible plastic pipe maintained by Nat ural Energy Laboratory ofHawaii Authority near Kona, Is Taxonomy land of Hawaii, 19°43'27.O1"N, 156°04'35.46"W (pipe in take 1 m diameter at depth off600m about 30m from the Tharybispseudomegalodactyla new species bottom) on 6 July 1997. These specimens may have been in Figures 1-6,15A the collecting net for up to 12 hours prior to fixation with 4% formaldehyde. Few internal tissues remain in these Holotype: dissected female 1.44mm (USNM 1027385); specimens, some exoskeletal structures are missing, and the prosome 1.12mm, urosome 0.32mm from eastern tropical prosome often is broken. Specimens collected from Vol Pacific Ocean l-5m above Volcano 7 (dive 2146, D8, N8). cano 7 (13°23'N; 102°27'W, dive 2145, D7, N4; dive 2146, Paratypes: 1 dissected male 1.16mm and 1 dissected fe D8, N8; and dive 2147, D9, N4, N8) in the eastern tropical male (body lost, slides with oral parts and swimming legs, Pacific Ocean by the submersible ALVIN 1-5m above bot (USNM 1027386), collection data same as holotype; I dis tom depths of 1291-1316m, 2945-3010m, 2973-2992m, sected female 1.38mm (USNM 1027387) from Volcano 7 respectively, in November 1988 were fixed at depth ofcap (dive 2147, D9, N8); 2 dissected females (1.32 and 1.24mm) ture with gluteraldehyde. Theirexoskeleton and internal tis and 1 dissected and 1 undissected male (1.12 and 1.22mm) sues appear intact. Ferrari & Markhaseva (1996, 2000a) (USNM 1027388) from Volcano 7 (dive 2147, D9, N4). give further details about collections from Volcano 7 and Hawaii, respectively. In the laboratory, specimens from both CVl Female. Total length 1.24-1.44mm. Prosome localities were preserved in 0.5% propylene phenoxytol/4.5 3.0-3.5 times longerthan urosome. Cephalon, Thl and Th2 % propylene glycol/95.0% de-ionized freshwater. During fused. Th5 and Th6 fused ventrolaterally (Fig. 1A). Dor- examination, specimens were cleared in steps through 50% sally cephalon rounded anteriorly (Fig. IB). Laterally pos lactic acid/50% de-ionized freshwater to 100% lactic acid, teriorcorners ofprosome rounded (Fig. 1A): in dorsal view stained by adding a solution ofchlorazol black E dissolved obtusely triangular (Fig. ID), reaching at least to the mid- in 70% ethanol/30% de-ionized freshwater, and examined length of genital complex. Posterior edge of urosome with bright-field and with differential interference optics. somite 2 with epicuticular fringe best seen in dorsal view Drawings were made with a camera lucida. Dissected and (Fig. ID). Genital complex slightly asymmetrical; in dorsal undissected specimens are preserved in 70% ethanol/30% view small swelling on the left side slightly more pro de-ionized freshwater. Specimens are deposited in National nounced than swelling on right (Fig. 1D, F, G). Museum ofNatural History, Smithsonian Institution, Wash Rostrum (Fig. 1C): 2 thin filaments. ington, D.C. (USNM). Al (Fig. 2A): reaching the posterior end ofTh4 and of Thoracic somitesare Thl-7. Prosome is cephalic somites 24 articulated segments: with groups of setae: 3, 6+1, 1-5 plus thoracic somites 1-6; urosome is thoracic somite 7 2+1,2,2+1,2,2+1,4+1, 1, 1, 1+ 1, 1,2+1, 1, 1, 1,2, plusall abdominal somites. Cephalic appendages are abbre l+ l, 1, 1,2,2,2,4+1. viated Al=antenna I; A2=antenna 2; Mn=mandible; A2 (Fig. 2B): coxa with 1 small seta; basis with 2 setae. Mxl=maxilla 1; Mx2=maxilla 2. Appendages on thoracic Ri 2-segmented; proximal segment with 2 setae and row of somites are Mxp=maxilliped (thoracopod 1); Pl-5=swim- small denticles distally; distal segment with 14 (6 terminal ming legs 1-5 (thoracopods 2-6). Re is exopod; Ri is endo- and 8 sub-terminal setae). Re 7-segmented (2nd and 3rd pod. The caudal ramus is CR. The length ofthe whole ani segments from basis incompletely articulated) with 0, 0 mal is measured from the anterior edge ofthe cephalon to (+1), 1, 1, 1, 1,3 setae. the posterior edge of the caudal ramus, and does not in Mn (Fig. 2C, D): coxa with row ofstiffdenticles origi clude that part of the prosome which overlaps the genital nating along medial edge ofgnathobase; basis with 3 setae. complex. Designations ofappendage segments follow Fer Ri 2-segmented, proximal with 2 setae and distal with 9 rari (1995) and Ferrari & Markhaseva (2000a). The coxa of setae. Re indistinctly segmented apparently with 1, I, 1, 1 the maxilliped ofcopepods is the distal setiferous lobe on and 2 setae. the calanoid syncoxa; the remaining three setiferous lobes Mxl (Fig. 2E): praecoxal endite vaulted distally, with 9 belong to the praecoxa (Ferrari & Ivanenko 2001; Ferrari & terminal, 4 posterior and 1 anterior setae; coxal endite with Dahms 1998). Articulating armament elements of ap 3 setae; proximal and distal basal endites with4 and 3 setae pendages are termed setae regardless oftheir location, mor respectively. Ri with 7 setae (2+2+3); Re with 3 setae and phology or degree ofrigidity. Two setae and one aesthetasc exitcwith 7 setae. ThreeNewSpeciesofTharybis 35 D Fig. 1. Thaiybispseudomegalodactyla, new species. Female. A, habitus, lateral; B, anterior part ofcephalon; C, rostrum, left lateral; D, posteriorcornersofprosomeand urosome,dorsal; E, urosome, left lateral; F,genital complex, ventral; G, genital com plex,dorsal. Figures B, C, Dfrom holotype; A, E, F,Gfromparatypes. Scalelines0.1 mm. Mx2 (Fig. 3): proximal praecoxal endite with 4 setae; PI (Figs. 4A, 15A): coxa without seta. Basis with small distal with 3 setae. Proximal coxal endite with 3 setae, pos lateral seta and medial seta; latter seta part oforgan ofVon terior seta a poorly-sclerotized, sensory seta without se- Vaupel Klein along with thumb-like knob on Ri (Fig. 15A); tules; distal coxal endite with 3 setae, including 1 thick distal edge ofknob smooth with 4-6 denticles on anterior spine-like seta. Proximal basal endite with 4 setae, I poorly face. Ri 1-segmented with 3 medial and 2 terminal setae. sclerotized sensory seta without setules, and 3 well sclero- Re 3-segmented, proximal with 1 lateral seta, middle with 1 tizedseta with setules. Distal basal lobe plus Re with 8 sen medial and 1 lateral seta, distal with 3 medial, 1 terminal, 1 sory setae; 5 brush-likeand3 worm-like. lateral seta; lateral seta on proximal segment exceeds the Mxp (Fig. 2F): syncoxa with 1 seta on proximal lobe; 2 base of terminal seta and lateral seta on middle segment setaeon middle lobe; 3 setae on distal lobe; coxal lobe with covers at least one third length oflateral seta on distal seg 3 setae and distal hairs; all setae sclerotized. Basis with row ment. ofstiff hairs proximally, 3 setae on unattenuated proximal P2 (Fig. 4B): coxa with medial seta. Basis without seta. lobe and 2 setae on distal lobe. Ri of5 articulated segments Re 3-segmented, proximal with 1 medial and I lateral seta, with4,4, 3, 4and4 setae. middle with 1 medial and 1 lateral seta, distal with 4 me- 36 F. D. Ferrari&E. L. Markhaseva A Fig. 2. Tharybispseudomegalodactyla, new species. Female. A. antenna I; B, antenna 2: C. mandibular palp; D, mandihular gnathobase; E, maxilla I: F, maxilliped. Figure B from holotype: figuresA, C-F from paratypes. Scalelines0.1 mm. dial, I terminal and 3 lateral setae. Proximal and distal seg middle with 1 medial and lateral seta, distal with 4 medial, ments with groups ofsmall surface denticles. Medial seg I terminal and 3 lateral setae. Medial segment with row of ment with row ofsmall denticles distally. Ri 2-segmented, small denticles distally. Distal segments with group ofsur proximal with I medial seta, distal with 2 medial, 2 termi face denticles. Ri 3-segmented, proximal with 1 medial nal and I lateral setae. Proximal and distal segments with seta, middle with 1 medial seta, distal with 2 medial, 2 ter groupsofsmall surface denticles. minal and 1 lateral seta. Middle and distal segments with P3 (Fig. 4C): coxa with medial seta. Basis without seta. groups ofsurface denticles. Re 3-segmented, proximal with I medial and I lateral seta, P5 (Fig. 4E, F): 3-segmented; coxa and basis unarmed. middle with I medial and 1 lateral seta, distal with 4 me Re (distal segment) 3.2X as long as wide [length along me dial, 1 terminal and 3 lateral setae. Proximal and distal seg dial face to width at origin of seta] with 1 articulated me ments with groups of surface denticles. Medial segment dial seta, slightly curved, with setules, 4.5X as longas wide with row ofsmall denticles distally. Ri 3-segmented, proxi [width at base to height at tip] and 2 spine-like attenuations, mal with 1 medial seta, middle with I medial seta, distal terminal with denticles. with 2 medial, 2 terminal and I lateral seta. Middle and dis CR (Fig. ID): 4 large, terminal setae, 1 small mediodor- tal segments with groupsofsurface denticles. sal seta and I small ventral seta. P4 (Fig. 4D): coxa with medial seta. Basis without seta. Re 3-segmented, proximal with 1 medial and 1 lateral seta, CVI Male. Total length 1.12-1.22mm. Prosome ThreeNewSpeciesofTharvbis 37 Fig. 3. Tharvbispseudomegalodactyla, new species. Female. Maxilla 2. From holotype. Scale lineO.I mm. Fig. 4. Tharybispseudomegalodactyla, new species. Female. A, PI, anterior; B, P2, posterior; C, P3, posterior; D, P4, poste rior; E. P5; F, P5 Re3. FiguresA, B,C, D from paratypes, Figs. E, F from holotype. Scale line 0.1 mm. 38 F. D. Ferrari&E. L. Markhaseva 2.2-2.7 times longer than urosome. Cephalon and Thl fused. Thl-Th2 separate dorsally. Th5-Th6 fused (Fig. 5A, B). Posterior corners ofprosome rounded laterally and dor sally. Genital openingon left. Rostrum (Fig. 5B): 2 small filaments. Al (Fig. 5C-E): right of 22 articulated segments: with groups of setae: 1+2, 5+4, 2+2, 2+1, 2+1, 2+I, 2+1, 4+5, 1+1,2+1, 1+1, 1+1, 1+ 1, l+ l, 1+1, 1 +1, 1+1, I, 2, 2, 2, 4+1. Left Al of 23 articulated segments; seg ment apparently homologous to the 18th ofthe right Al ap pears divided into 2 segments in left Al with the proximal segment lackingseta. A2: as forfemale, exceptforbasiswith 1 seta. Mn: as for female, except for Ri2 with 8 setae. Mx1: as for female except for praecoxa lacking anterior setaand exite with 8 setae. Mx2, Mxp and P1-P2 as for female. P3-P4: as for female except surface denticulation less dense. P5 (Fig. 6A-E): right leg uniramal 4-segmented; Re 2- segmented, Rel with several knob-like attenuations along middle ofsegment. Left leg biramal, Ri 1-segmented falci form, thin, narrowing distally. Re 3-segmented; middle seg ment with distal flange around proximal part ofdistal seg ment; distal segment with flange around 2 terminal attenua tions. Etymology D The name recognizes a general similarity of the species to Tharybismegalodactyla Andronov, 1976. Fig. 5. Thaiyhis pseudomegalodactyla, new species. Male. A, habitus, dorsal; B, habitus, lateral; C, right antenna 1, articulated Remarks segments 1-11; D, rightantenna 1, articulated segments 12-19; E, right antenna 1, articulated segments20-22. From paratype. Scale Female and male specimens have been assigned to the lines0.1 mm. same species based on their co-occurrence, and identical Fig. 6. Tharybis pseudomegalodactyla, new species. Male. A, B, P5 in different views; C-E. left P5 Re3 in different views. RcM is middlesegmentofexopod; ReD is distal segment ofexopod; Ri isendopod. From paratype. Scale lines0.1 mm. ThreeNewSpeciesofTharybis 39 number and kind of sensory setae on maxilla 2 and the maxilliped. Females of T. pseudomegalodactyla share sev eral features with females of Tharybis magna Bradford, 1983 (in Bradford & Wells 1983) and Tharybis megalo- dactyla Andronov, 1976. The new species shares with T. megalodactyla a leg 5 of similar general shape, 5 brush- like sensory setae on the basis plus ramus ofmaxilla 2; it differs from T. megalodactyla by the asymmetrical genital complex (symmetrical in T. megalodactyla), larger size (1.10-1.24mm T. megalodactyla), and curved seta on P5 (straight in T. megalodactyla). Tharybis pseudomegalo dactyla shares with T. magna an asymmetrical genital com plex with more pronounced bump on the left side, similar leg 5, and all setae sclerotized on the syncoxa ofthe maxil liped, as recently redescribed by Ohtsuka et al. (1998). Tharybis pseudomegalodactyla is distinguished from T. magna by the presence of5 brush-like sensory setae on the basis plus ramus ofmaxilla 2 and 8 transformed setae in total (7^ magna has 6 brush-like sensory setae and 9 trans formed setae in total) and smaller size {T. magna is 1.50-1.70mm). Males of T. pseudomegalodactyla differ significantly in the structure of leg 5 from males of the above mentioned two species as well as from males all known species of Tharybis. Males of T. pseudomegalo dactyla differ from T. megalodactyla which has knob-like attenuation on the proximal exopodal segment ofthe right leg 5 and in the shape ofthe left endopod which is curved significantly. Males of the new species are distinguished from T. magna which has a knob-like attenuation on the distal segment ofthe right leg 5 and a distal segment ofthe left exopod without flanges (Bradford & Wells 1983); this also is the case for T. altera, T. asymmetrica, T. compacta, T. groenlandica and 7! minor. Tharybisfultoni, T. macroph- Fig. 7. Tharybisjuhlae, new species. Female. A, habitus, left thalma and T. inaequalis have a complicated distal left Re, lateral; B, posterior corners ofprosome and urosornc, dorsal; C, but the shape ofthe distal segment ofthe right exopod of same, right lateral; E, genital field, leftlateral; F, genital field, ven leg 5 ismore complexthan thatofT.pseudomegalodactyla. tral. From paratypes. Scale line0.1 mm. Tharybisjuhlae new species complex. Urosomites with epicuticular fringe (Fig. 7B, C). Genital complex symmetrical, nearly as long as following 2 Figures 7-12,15C urosomites together, with low dorsal knob laterally at about Holotype: female 1.69mm; prosome 1.28mm, urosome mid length (Fig. 7A, C). Genital field in the anteriorpart of 0.41 mm collected 6 July 1997 nearKona, Island ofHawaii, genital complex (Fig. 7E, F). 19°43'27.01"N, 156°04'35.46"W (USNM 1027390). Rostrum: 2 thin filaments (Fig. 7D). Paratypes: 4 dissected females (1.42, 1.59, 1.61 and Al (Fig. 8A, B): reaching to the end ofTh3; 24 articu 1.63mm) whose lengths could be accurately measured and lated segments with groups of: 3, 6, 2+2, 2, 1+1+?, 2, 4 undissected females. One dissected male, total length 2+1,4+1,?, ?+l, ?, 1+1, 1+1+?, 1, 1+?, 1, 1 +1+?, 1, 1.36mm (same data as holotype) (USNM 1027391); 2 dis 1, 1,2,2,2,4+1 setae. sected males (1.42, 1.48mm) from Volcano 7 (dive 2145, A2 (Fig. 8C): coxa without seta; basis with 2 setae. Ri 2- D7, N4)(USNM 1027392). segmented; proximal segment with 2 setae and distal with 14 (6 terminal and 8 subterminal setae). Re 8 segmented CVI Female. Total length 1.42-1.69mm; prosome with 0,0, 1, 1, 1, 1, 1,3 setae. 3.0-3.4 times longer than urosome; cephalon and Thl Mn (Fig. 8D-F): coxal gnathobase with row ofstiffhairs; fused, Th5-Th6 fused dorsally, in lateral view both arthro- basis with 3 setae. Ri 2-segmented; proximal segment with dial membranes present (Fig. 7A, C). Posterior corners of 2 setae, and distal with 9 setae. Re indistinctly segmented prosome rounded in lateral view (Fig. 7A, C) and triangular apparently with 1, 1, 1, 1 and2 terminal setae. in dorsal view (Fig. 7B), reaching to mid-length ofgenital Mxl (Fig. 8G): praecoxal endite vaulted distally with 10 40 F. D. Ferrari&E. L Markhaseva B Fig. 8. Tharybisjuhlae, new species. Female. A, antenna I. articulated segments 1-9; B, antenna I, articulated segments 10-24; C, antenna 2; D, mandibular palp; E, mandibular gnathobase: F. cutting edge ofmandibular gnathobase; G, maxilla 1. From paratype. Scale lines0.1 mm. terminal, 3 posterior and 1 anterior setae; coxal endite with dial seta curved back upon itself, degree ofcurvature varies 3 setae, proximal and distal basal endites with 4 setae and 3 (compare Fig. 10A with Fig. 15C); organ of Von Vaupel setae respectively. Ri with 2, 2, 5 setae; Re with 4 setae and Klein with pronounced thumb-like knob on Ri; distal edge exitewith 9 setae. of knob smooth, without ornamentation on anterior face, Mx2 (Fig. 9A, B): proximal praecoxal endite with 4 with long, thin denticles behind the knob extending toward setae; distal with 3 setae. Proximal coxal endite with 3 distal margin ofendopod (Fig. 15C). Re 3-segmented, prox setae; distal coxal endite with 3 setae, of them 1 thick, imal with 1 lateral seta, middle with 1 medial and I lateral spine-like. Proximal basal endite with 4 setae, distal basal seta, distal with 3 medial, I terminal, 1 lateral seta; lateral lobe plus Re with 5 brush-like, 3 worm-1ike and 1 sclero- seta on proximal segment reaches the base ofterminal seta tized seta, latterwith sparse setules. and lateral seta on middle segment reaches nearly the mid- Mxp (Fig. 9C): syncoxa with 1 seta on proximal lobe, 2 length oflateral setaon distal segment. setae on middle lobe, 3 setae on distal lobe, coxal lobe with P2 (Fig. 10B): coxa with medial seta; basis without seta. 3 setae and distal hairs; all setae sclerotized. Basis with row Re 3-segmented, proximal with 1 medial and 1 lateral seta, of stiff hairs proximally, 3 setae on unattenuated proximal middle with 1 medial and lateral seta, distal with 4 medial, lobe and 2 setae on distal lobe. Ri of5 articulated segments 1 terminal and 3 lateral setae. Distal segment with group of with 4, 4, 3, 4and4setae. small surface denticles. Ri 2-segmented, proximal with 1 PI (Figs. 10A, 15C): coxa without seta. Basis with a me medial seta, distal with 2 medial, 2 terminal and 1 lateral ThreeNew SpeciesofTharybis 41 Fig. 9. Tharybisjuhlae, new species. Female. A, maxilla 2 (without distal basal lobe and Re); B, maxilla 2, distal basal lobe plus Re. From paratypes. Scale lineO.I mm. setae. Distal segment with groups of small surface denti cles. P3 (Fig. IOC): coxa with medial seta; basis without seta. Re 3-segmented, proximal with 1 medial and 1 lateral seta, middle with 1 medial and lateral seta, distal with 4 medial, I terminal and 3 lateral setae. Distal segment with groups ofsurface denticles. Ri 3-segmented, proximal with 1 me dial seta, middle with 1 medial seta, distal with 2 medial, 2 terminal and I lateral seta. Middle and distal segments with groups ofsurfacedenticles. P4 (Fig. 10D): coxa with medial seta; basis without seta. Re 3-segmented, proximal with 1 medial and 1 lateral seta, middle with 1 medial and lateral seta, distal with 4 medial, 1 terminal and 3 lateral setae. Ri 3-segmented, proximal with 1 medial seta, middle with 1 medial seta, distal with 2 medial, 2 terminal and 1 lateral seta. All segments with groups ofsurfacedenticles. P5 (Fig. 10E): 3-segmented; coxa and basis unarmed. Re [distal segment] 6.5X as long as wide [length along medial face to width at origin ofseta] with 1 small lateral seta at mid-length and 1 terminal, medial seta with setules, 10.5X as long as wide [width at base to height at tip], 2 spine-like attenuations with denticles, and lobe at base of terminal seta. CR (Fig. 7B, C): 4 large terminal setae, very small dorsal and small ventral seta; dorsal surface with small denticles. CVl Male. Total length 1.36-1.48mm; prosome Fig. 10. Tharybisjuhlae. Female. A. PI; B, P2; C, P3; D, P4; E, 2.3-2.8 times longerthan urosome. Cephalon and Thl-Th2 P5. Fromparatypes. Scalelines0.1 mm. fused, Th5-Th6 fused dorsally (Fig. 11A). Posteriorcorners 42 F. D. Ferrari& E. L Markhaseva Fig. 11. Tharybisjuhlae, new species. Male. A. habitus, left lateral; B, posterior corners ofprosome, urosome and P5; C, posteriorcornersofprosomeand urosome; D. fourth Fig. 12. Tharybisjuhlae, new species. Male. A, P4; B-E. P5 different somite of urosome and anal somite; E, rostrum. From views; F-I. left Rc3 P5. ReM is middle segment ofexopod; Ri is endopod. paratype. Scale lines0.1 mm. Fromparatypes. Scale line is0.05mm forI: and0.1 mm forallotherfigures. ofprosome rounded in lateral view, in dorsal view slightly Left biramal, Ri 1-segmented falciform; Re 3-segmented; asymmetrical (Fig. 11C). Genital opening on left. Anal middle segment with spine-like attenuation; distal segment somite small, often obscured by somite anterior to it (Fig. complex with 2 digitiform appendages and a flange with 11C, D). denticles along its baseandaround its edges. Rostrum (Fig. 11E): 2 filaments. AI (Figs. IIA, 15B): right of 22 articulated segments: Etymology with groups of setae: 1 +1, 5+4, 2+2, 2+1, 1+2, 2+1, The species name honors Dr. Hildegard Juhl who has cu- 2+2, 4+4, 1 + 1, 2+1, 1+1, 2+1, 2+1, 2+1, 1+ 1, 2, rated the MONOCULUS Copepod Library at the Univer 1 +1, 1, 2+1, 2, 2, 4+1. Left Al of 23 articulated seg sity ofOldenburg in Germany since its inception. ments; segment apparently homologous to the 18th of the right A1 appearsdivided into 2 segments in left Al with the Remarks proximal segment lacking seta (see Fig. I5B). A2: as for female. Female and male specimens have been assigned to the Md: as forfemale, except for Ri2 with 8 setae. same species based on their co-occurrence and identical Mxl: as for female except proximal praecoxal endite number and kind of sensory setae on maxilla 2 and the without anteriorseta andcoxal exite with 7 setae. maxilliped. Females ofTharybisjuhlae differ from all other Mx2, Mxp and P1-P2 as forfemale. species ofthe genus in the shape ofgenital complex which P3: asforfemale except sparsersurfacedenliculation. is very long in dorsal view (nearly as long as two following P4: as for female except semicircular chitinous ridge at somites), and has a knob visible in lateral view. It shares basipod(Fig. 12A). with T. macrophthalma, T, fitltoni, T. macrocephalon, T. P5 (Figs. 11B, 12B-I): right uniramal. Re 2-segmented. paraincertus and T. macrophthalmoida a lateral seta (or at-