Four new free-living marine nematode species (Sabatieria) from the Chukchi Sea Author Yang, Peipei Author Guo, Yuqing Author Chen, Yuzhen Author Lin, Rongcheng text Zootaxa 2019 2019-07-23 4646 1 31 54 journal article 26154 10.11646/zootaxa.4646.1.2 4a3c3d05-da85-48ec-8fa3-1a855dc7121e 1175-5326 3346313 59DA470E-A7CA-4074-B964-42F937380F5A Sabatieria multisupplementia sp. n. ( Figures 11–12 , Table 4 ) Type material. Three males were collected from station CC 1. Holotype : ♂ 1 on slide number Chukchi20100720 CC14202 . Paratypes : ♂ 2 on slide number Chukchi20100720 CC14103 , ♂ 3 on Chukchi20100720 CC13102 . TABLE 4. Morphometrics (µm) of Sabatieria major sp. n. and Sabatieria multisupplementia sp. n.

Characters	Sabatieria major sp. n.	Sabatieria multisupplementia sp. n.
Male	Males	Females	Male	Males
holotype	Paratypes	Paratypes	holotype	Paratypes
n	-	4	2	-	2
Total body length	4255	3972±116 (3879–4171)	4081–4197	4294	3967–4080
a	28	26±2 (24–28)	21–24	25	26–28
b	12	12	11–13	11	10–11
c	14	12±1 (11–13)	12	15	13 –14
Head diameter	27	23±1 (21–24)	23–24	26	25–26
Length of cephalic setae	7	5±1 (4–6)	5	5	6–7
Amphideal fovea from anterior end	-	10±1 (9–11)	8–10	12	10 –13
Amphideal fovea diameter	10	13±1 (12–14)	12–13	15	14
Amphideal fovea diameter / corresponding body diameter (%)	-	50±4 (45–56)	44–50	52	48
Nerve ring from anterior end	169	180±7 (169–186)	191–197	206	193–210
Nerve ring / pharyngeal length (%)	49	54±2 (51–56)	53–58	54	51–55
Excretory pore from anterior end	-	200±9 (188–210)	196–223	235	217–219
Pharyngeal length	347	332±4 (327–339)	333–374	379	376–379
Pharyngeal end corresponding body diameter	109	115±8 (102–122)	120–132	125	113–133
Maximum body diameter	154	157±11 (138–166)	168–203	169	148–154
Vulva from anterior end	-	-	1897–2087	-	-
V (%)	-	-	46–50	-	-
Spicule length along arc	185	177±2 (175–181)	-	180	175–183
Spicule length along chord	163	157±3 (153–161)	-	149	139–152
Gubernacular apophyses length	81	76±5 (70–84)	-	62	59–63
Number of pre-cloacal supplements	30	27±7 (17–32)	-	47	41
Anal or cloacal body diameter	102	106±9 (91–115)	103–105	97	89–105
Tail length	314	346±14 (328–367)	347–351	291	295–299
c’	3.1	3.3±0.3 (2.9–3.7)	3.3–3.4	3.0	2.8–3.4

FIGURE 8. Sabatieria maJor sp. n. A: lateral view of male anterior part; B: lateral view of male tail and spicule; C: lateral view of female anterior part; D: lateral view of female tail. Scale bar = 20 µm. FIGURE 9. Sabatieria maJor sp. n. A: lateral view of male head; B: lateral view of female reproductive system. Scale bar: A = 20 µm; B = 100 µm. FIGURE 10. Sabatieria maJor sp. n. Male: (A) lateral surface view of head region (amphideal fovea; cephalic setae); (D) copulatory apparatus; (E) pre-cloacal supplements; (I) spicule and tail. Female: (B) lateral surface view of head region (amphideal fovea; cephalic setae); (C) lateral surface view of head region (buccal cavity); (F) vulva region; (G) lateral differentiation (anterior body); (H) rectal region and tail. Scale bar = 10 µm. FIGURE 11. Sabatieria multisupplementia sp. n. A: lateral view of male anterior part; B: lateral view of male tail and spicule; C: lateral view of male head; D: lateral view of pre-cloacal supplements. Scale bar: A, B = 25 µm; C =20 µm; D =50 µm. FIGURE 12. Sabatieria multisupplementia sp. n. Male: (A) lateral surface view of head region (amphideal fovea; cephalic setae); (B) lateral surface view of head region (buccal cavity); (C) lateral differentiation (anterior body); (D) pre-cloacal supplements; (F) copulatory apparatus; (F) spicule and tail. Scale bar=10 µm. Type locality and habitat. All specimens were collected from the Chukchi Sea ( 52 m water depth). Station CC 1: 67.6722°N , 168.9562°W . Median grain diameter: 5.35 Md Φ , Sand: 33.34%, Silt: 58.02%, Clay: 8.63%. Etymology. The species name is derived from the latin prefix multi- (= many) and supplementia (=supplement), and refers to the many pre-cloacal supplements in this species relative to other species of the genus. Measurements. Table 4 . Description. Male. Body cylindrical, tapering slightly towards both extremities. Cuticle with transverse rows of dots, lateral differentiation consisting of larger, irregularly-spaced dots. Two dorso- and two ventro-lateral rows of short, sparse somatic setae. Three crowns of anterior sensilla: six indistinct inner labial papillae, six short but distinct outer labial setae and four long cephalic setae. Buccal cavity cup-shaped. Amphideal fovea spiral with 2.75–3 turns, located immediately posterior to cephalic setae. Pharynx gradually swelling towards posterior, not forming true bulb. Nerve ring 193–210 µm from anterior end of body, at 51–55% of the pharyngeal region length. Excretory pore 217–235 µm from anterior end of body, at 57–62% of the pharyngeal region length. Tail 291–299 µm long, conico-cylindrical with four rows of sparse short caudal setae and three short terminal setae. Reproductive system diorchic with outstretched testes. Anterior testis to the left of intestine, posterior testis to the right of intestine. Spicules paired, equal, arcuate, equal to 1.7–2.0 cloacal body diameters in length, and with central cuticularised projection (lamella) extending from proximal end to one half of spicule. Gubernaculum surrounding the distal part of the spicules, and with 59–63 µm long, paired, straight apophyses. Forty-one to fortyseven tubular pre-cloacal supplements, followed by one pre-cloacal seta. Three caudal glands situated posterior to spicule. Spinneret present. Female . Not found. Diagnosis and relationships. Sabatieria multisupplementia sp. n. is characterized by a long body ( 3967–4294 µm ), short cephalic setae ( 5–7 µm , equal to 20–25% of head diameter), amphideal fovea spiral with 2.75–3 turns, and forty-one to forty-seven tubular pre-cloacal supplements. Sabatieria multisupplementia sp. n. belongs to the praedatrix group and can be differentiated from all other species of the genus by its 41–47 pre-cloacal supplements. S. multisupplementia sp. n. resembles S. bubulba in lateral differentiation and presence of central cuticularised projection (lamella) extending from proximal end to one half of spicule, but can be distinguished from the latter by longer total body length (3967–4294 vs 1520–1750 µm ) and longer spicules (equal to 1.7–2.0 vs 1.4–1.7 cloacal body diameters).