Stenopleustes jeskulkeae, Lörz & Tandberg, 2025

Stenopleustes jeskulkeae sp. nov.

urn:lsid:zoobank.org:act:68BB5166-88EA-42C5-9F9B-BC91914B2DF1

Figs 1D–F View Fig , 20–27 View Fig View Fig View Fig View Fig View Fig View Fig View Fig View Fig

Stenopleustes aff. nodifera A Schwentner & Lörz, 2021 View in CoL : fig 3, tab. 1.

Diagnosis

Pereon and third epimeral plate dorsally smooth, without carination, first two pleonites dorsally with two pointed extensions each.

Etymology

Stenopleustes jeskulkeae is named for our good colleague Karen Jeskulke, who tirelessly helped with keeping order in all our specimens. The name is derived of the Latin genitive of her surname.

Type material

Holotype

ICELAND – off Reykjanes • ♀ adult, 7.3 mm, ethanol fixed; Reykjanes Ridge; 59.251°N, 30.484383°W; depth 866 m; 17 Jul. 2018; MSM 75, IceAGE-RR exped., station 80-11; collected by ROV KIEL6000, from Plexauridae / Paramuricea ; AMPIV 308-22; ZMH-K 60037.

Paratypes

ICELAND – off Reykjanes • 3 specs., SEM-stubs; same data as for holotype; DZMB 61788 a-c .

Additional material

ICELAND – off Reykjanes • 1 spec., ethanol fixed; same data as for holotype; ZMH-K 58759 • 3 specs, SEM-stubs; same data as for holotype; DZMB 61787a-c • 1 spec.; same data as for holotype; AMPIV 312-22; DZMB 62368 • 1 spec.; same data as for holotype; AMPIV 313-22; DZMB 62369 • 1 spec.; same data as for holotype; DZMB 61800_d • 1 spec.; same data as for holotype; AMPIV 314-22; DZMB-HH _62370 • 1 spec.; same data as for holotype; AMPIV 315-22; DZMB-HH _62371 • 3 specs.; Reykjanes Ridge; 59.24786°N, 30.488983°W; depth 869 m; 28 Jul. 2018; MSM 75, IceAGE-RR exped., station 149-6; collected by ROV KIEL6000, from Plexauridae / Paramuricea ; ZMH-K 58760 • 1 spec.; Reykjanes Ridge; 60.24765°N, 29.1379°W; depth 718 m; 13 Jul. 2018; MSM 75, IceAGE-RR exped., station 67-6; collected by ROV KIEL6000, from Paragorgia arborea ; ZMH-K 58765 • 1 spec.; same data as for preceding; ZMH-K 58767 • 1 spec.; same data as for preceding; ZMH-K 58768 • 1 spec.; same data as for preceding; ZMH-K 58769 • 1 spec.; same data as for preceding; AMPIV 304-22; DZMB-HH 62314 • 1 spec.; same data as for preceding; AMPIV 301-22; DZMB-HH 62311 • 1 spec.; same data as for preceding; AMPIV 302-22; DZMB-HH 62312 • 1 spec.; same data as for preceding; AMPIV 305-22; DZMB-HH 62315 • 1 spec.; same data as for preceding; AMPIV 306-22; DZMB-HH 62316 • 1 spec.; Reykjanes Ridge; 60.237°N, 29.136°W; depth 705 m; 1Aug. 2018; MSM 75, IceAGE-RR exped., station 188-4; collected by ROV KIEL6000, from Paramuricea ; AMPIV 320-22; DZMB-HH _61711 • 1 spec.; Reykjanes Ridge; 60.23625°N, 29.1288°W; depth 646 m; 1 Aug. 2018; MSM 75, IceAGE-RR exped., station 188-5; collected by ROV KIEL6000, from Paramuricea ; AMPIV 318-22; DZMB 61715 • 5 specs; same data as for preceding; DZMB 62851_b • 12 specs; same data as for preceding; DZMB 62852_b.

Description

Rostrum small, about 0.2 times as long as peduncular segment of antenna 1, apex acute; anterior head angular.

Eyes very large, reniform, covering almost length of head. Antenna 1–2 very long, A1 as long as body; A1 peduncular segment 1 elongate and strong, equal to segments 2–3 together; flagellum length about 5 times as long as peduncle with more than 60 articles. Antenna 2 nearly as long as antenna 1, flagellum with more than 50 articles.

Upper lip oval, strong, smooth. Lower lip with dense setae outer lobes. Mandible palp very large, second segment 2 × as long as first and 0.8 × as long as third segment. Mandibular palp segment 1 smooth, second article nine setae, third article with ten strong pectinate setae at inner apical margin, anterior tip with two smaller pectinate setae, inner side of mandibular palp densely setose, left and right mandibular palp alike, molar strongly triturative, 12 teeth at the incisor, with 14 teeth also at lacinia mobilis.

S. jeskulkeae S. eldingi S. latipes (M. Sars, S. malmgreni (Boeck, S. nodifer (G.O. S. olriki S. rainbowi sp. nov Gurjanova, 1858) 1871) Sars, 1883) (Hansen, Bellan- 1930 1888) Santini, 2007

Eyes large, depth large, half large, depth ashead large, depth ashead large, depth small, half absent ashead depth of head ashead depth of head

Coxa 1 same depth as missing in shorter than 2 same depth, rounded same depth, C2 description squarish

Peropod weakly slightly transverse, oblique, rounded, oblique,

2 palm oblique, weak oblique sculptured incision smooth rounded, smooth u-shaped serrated incision

Coxa 5 evenly lobate missing in deeply postereo- deeply postereo-lobate deeply postereodescription lobate lobate

Pereonite smooth smooth smooth smooth smooth dorsally

Pereonite smooth smooth blunt process smooth double

7 dorsally cuspidate

Dorsal 2 pointed smooth carina smooth 2 rounded sculpting extensions extensions epimeron

1 and 2

shorter than 2

oblique, with strong palmar protrusion deeply posterolobate smooth smooth smooth same depth as C2

transverse, not sculptured deeply posterolobate blunt process blunt process strongly bumpy

Maxilla 1 palp extending over outer plate, apex subtruncate, with a row of 7 cuspidate setae, inner plate with one terminal setae.

Maxilla 2, inner plate slightly shorter and broader than outer plate; outer plates with 8 long setae at terminal end, inner plate with 3 long setae at terminal end, inner margin of outer plates setose.

Maxilliped, inner plate short, apex inner angle subtruncate, outer rounded; outer plate longer than first palp segment, apex narrowly subtruncate; palp narrow, segment 2 subequal in length to segment 3; articles one to three with row of setae at inner side, dactylus erect at two thirds of third palp article, slender, slightly curved.

Coxa plate 1 lower margin slightly rounded, coxa 2–3 similar, coxae 4 much wider, margin slightly rounded. Coxal plate 5–6 broadly posterolobate, coxal plate 7 squareish.

Gnathopods 1–2 subchelate, similar in shape. Merus posteriorly extended, carpus broad, as long as propodus, long pectinate setae on inner margin; propodus with groups of pectinate setae, palm serrate with four strong setae, on inner margin up to mid palm; dactylus slender with inner rim, reaching more than half the length of propodus.

Pereopods 3–4 similar in shape. Pereopods 5–7 basis strong ridge, entire length. Pereopods 5–6 basis slightly rounded, basis of pereopod 7 convex. Merus of pereopodS 5–7 drawn out posteriorly.

Epimeral plate 1 smooth, epimeral plateS 2–3 with ridge, slightly drawn out posteroventral corner. Dorsally epimeral plates 2–3 have two small pointed extensions. Pleopods regular.

Uropod 1, peduncle same length as inner ramus; margins of peduncle and rami with short spine-like setae, the tip of both rami bear three distinct spines. Uropod 2, peduncle slightly shorter than inner ramus; margins of peduncle and rami with short spine-like setae, outer ramus length more than half of inner ramus; the tip of inner ramus bearing distinct spines. Uropod 3 inner ramus more than twice as long as peduncle, with strong spine like setae.

Telson triangular, entire, with two plumose setae on both apical margins.

Ecology and distribution

Found on the corals Paragorgia Milne-Edwards, 1857 , Plexauridae Gray, 1859 , Acanthogorgia Gray, 1857 and Paramuricea Kölliker, 1865 at dephts of 705– 980 m. (For further information, see Table 4.)

Taxonomic remarks

The new species is morphologically similar to Stenopleustes nodifer (G.O. Sars, 1883) ; however, the latter has rounded dorsal projections on the posterior edges of pleonites 1–2, with a deep u-shaped elevation whereas Stenopleustes jeskulkeae sp. nov. has pointed small tips.

There is a morphological variation.

Three juveniles of 2.0 mm length were taken from the marsupium of the holotype of Stenopleustes jeskulkeae sp. nov., these have much larger heads and thicker antennae in comparison to the adults.

The colour of the eyes of freshly caught individuals appears to be red for adults, and white for juveniles.

New BOLD numbers: AMPIV 320-22; AMPIV 304-22; AMPIV 301-22; AMPIV 302-22; AMPIV 305- 22; AMPIV 306-22; AMPIV 307-22; AMPIV 308-22; AMPIV 312-22; AMPIV 313-22; AMPIV 314-22; AMPIV 315-22; for details see Supp. file 2.

Stenopleustes jeskulkeae sp.nov. has the following Genbank numbers, named as Stenopleustes nodifera A in Schwentner & Lörz (2021) MT317332 View Materials – MT317339 View Materials , MT317343 View Materials – MT317352 View Materials , MT317354 View Materials - MT317357 View Materials , MT317360 View Materials , MT317362 View Materials , MT317366 View Materials , MT317368 View Materials , MT317369 View Materials – MT317381 View Materials , MT317385 View Materials , MT317386 View Materials , MT317387 View Materials , MT317390 View Materials - MT317392 View Materials , MT317397 View Materials - MT317400 View Materials .