Notopterophorus glabrus, Kim & Boxshall, 2020

Kim, Il-Hoi & Boxshall, Geoff A., 2020, Untold diversity: the astonishing species richness of the Notodelphyidae (Copepoda: Cyclopoida), a family of symbiotic copepods associated with ascidians (Tunicata), Megataxa 4 (1), pp. 1-6 : 142-145

Notopterophorus glabrus sp. nov.

( Figs. 93 , 94 )

Typematerial. Holotype (intact ♀, MNHN-IU-2017- 2145 ) , paratypes (2 intact ♀♀, MNHN-IU-2014-21245) from Ascidiainterrupta Heller, 1878 (MNHN-IT-2008- XXX = MNHN P5/ ASC.A/436), Pointe Burgos, Les Anses-d’Arlet, Martinique, MADIBENTHOS exped., (14°29.6 Ń, 61°05.5 Ẃ), depth 5–25 m, MNHN coll., 07 September 2016.

Additional material. 1 ♀ (MNHN-IU-2017- 2146) and 1 disscted ♀ (figured) from A. interrupta, MADIBENTHOS AR 051, Martinique, (14°26.9 Ń, 60°54 Ẃ), depth 3–20 m, 11 September 2016; 1 ♀ (MNHN-IU-2017-2155)from Microcosmusanchylodeirus Traustedt, 1883, Martinique, (14°31.7 Ń, 61°05.3 Ẃ), depth 6 m, 06 September 2016; 1 ♀ (MNHN-IU-2017- 2157) from Phallusia sp., MADIBENTHOSStnAR 415, Martinique (14°50.5 Ń, 61°13.7 Ẃ), depth 22–31 m, 01 October 2016.

Etymology. The specific name is derived from the Latin glab (= smooth), referring to the smooth wings on the pedigerous somites.

Descriptionoffemale. Body ( Fig. 93A, B ) large, 9.30 mm long. First to fourth pedigerous somites each bearinglarge dorsolateralextensionswithsmooth margins, lacking any filiform processes: extensions subcircular on first and fourth pedigerous somites, broad and winglike on second and third pedigerous somites. Fourth pedigerous somite forming brood pouch, fused to short fifthpedigerous somite. Freeurosome ( Fig. 93C ) small, obscurely segmented: genital somite articulated from fifth pedigerous somite; abdominal somites indistinctly defined. Three abdominal regions recognizable by lateral constrictions and areas of wrinkled integument. Caudal rami conical, obscurely defined from anal somite, about twice as long as wide (629×320 μm), smooth, lacking caudal setation elements.

Rostrum ( Fig. 93D ) small, triangular, ornamented with 1 sensilla on each lateral margin. Antennule ( Fig. 93E ) small, slender, graduallynarrowing distally; 8- segmented; armatureformula 2, 15, 9+aesthetasc, 3, 2+aesthetasc, 2, 2+aesthetasc, and 7+aesthetasc; all setae thin and short. Antenna ( Fig. 93F ) slender, 3-segmented; coxa and allobasis unarmed; free endopodal segment about 3.6 times longerthan wide (205×57 μm), slightly shorter than basis; armed with about 8 small setae plus terminal claw, about half as long as segment.

Labrum ( Fig. 93G ) covered with ornamentation of setules along posterior margin, with prominent posterolateral lobes. Mandible ( Fig. 93H ) with 8 teeth and 2 small setae on coxal gnathobase; basis with 1 medial seta; exopod unsegmented with 5 subequal setae; endopod with 3 and 8 setae on first and second segments, respectively. Paragnath ( Fig. 93I ) with 1 apical and 1 subapical dentiform processes and row of setules on medial marginand anterior surface. Maxillule ( Fig. 93J ) with 10 setae on arthrite, 1 on coxal endite, 2 on epipodite, and 4 on basis, second proximal seta larger than other 3; exopodwith 4 setae distally; endopodwith 2 setaeon medial margin of first segment and 3 on second. Maxilla ( Fig. 94A ) 5-segmented; syncoxa with 10 setae arranged as 4, 1, 2, and 3; basis with 1 slender, smooth claw plus 2 setae; endopod slender with 1, 1, and 4 setae on first to third segments, respectively; articulation indistinct between second and third segments. Maxilliped ( Fig. 94B ) 3-segmented; armedwith 9, 1, and 3 setaeonfirst to third segments, respectively; articulation incomplete between proximal 2 segments.

Legs 1–4 with 3-segmented rami ( Fig. 94 C–E); exopods and endopods almost equal in length. All legs with inner coxal seta, small outer seta on basis, and inner seta on first exopodal segment. Inner distal spine on basis slender and shorter than first endopodal segment. Spines on third exopodal segment of legs 2–4 equal in length. Armature formula for legs 1–4 as follows:

	Coxa Basis Exopod			Endopod
Leg 1	0-1	1-I	I-1; I-1; III, I, 4	0-1; 0-1; 1, 2, 3
Legs 2 & 30-1		1-0	I-1; I-0; III, I, 0	0-1; 0-2; 1, 2, 3
Leg 4	0-1	1-0	I-1; I-0; III, I, 0	0-1; 0-2; 1, 2, 2

Leg 5 ( Fig. 94F ) consistingof protopod and exopod. Protopod longerthan wide, notarticulated from somite, bearing 1 naked seta on slightly projecting outer distal corner and several fine spinules near mediodistal corner. Exopodal segment elongate, gradually narrowing distally, about 4.5 times longer than wide (313×69 μm), armed distally with 1 small setiform spine and 1 naked seta, and ornamented with about 10 rows of fine spinules on medial surface.

	Coxa	Basis	Exopod	Endopod
Leg 1	0-0	1-I	I-1; I-1; III, 4	0-1; 0-1; 1, 2, 3
Leg 2	0-0	1-0	1-0; 1-0; 3, 1, 1	0-1; 1, 3, 1
Leg 3	0-0	1-0	1-0; 1-0; 3, 1, 1	0-0; 0, 2, 1
Leg 4	0-0	0-0	I-1; I-0; 2, 1, 1	0-0; 0, 2, 0

Male. Unknown.

Remarks. The structure and armature of the appendages in previously described species of Notopterophorus are relatively uniform, as mentioned above. Notopterophorus glabrus sp. nov. deviates from this uniformity and is clearly defined from its congeners. It has 3 and 8 setae (rather than 4 and 10 setae as usual for the genus) on the first and second segments of the mandibular endopod, 5 (2+3) setae (rather than 6 or 7 setae as usual) on the maxillular endopod, and 3 setae (rather than 4) on the third segment of the maxilliped. The presence of an inner seta on the first exopodal segment of leg 4 of the new species is also an unusual feature in Notopterophorus . These differences are sufficient to justify the establishment of the new species.

Figures

FIGURE 93. Notopterophorus glabrus sp. nov., female. A, habitus, right; B, habitus, dorsal; C, urosome, ventral; D, rostrum; E, antennule; F, antenna; G, labrum; H, mandible; I, paragnath; J, maxillule. Scale bars: A, B, 1 mm; C, 0.5 mm; D, 0.05 mm; E–J, 0.1 mm.

FIGURE 94. Notopterophorus glabrus sp. nov., female. A, maxilla; B, maxilliped; C, leg 1; D, leg 2; E, leg 4; F, leg 5. Scale bars: 0.1 mm.