Stenopleustes jeskulkeae, Lörz & Tandberg, 2025

Stenopleustes jeskulkeae sp. nov.

urn:lsid:zoobank.org:act:

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; MSM75 , IceAGE-RR exped., station 80-11; collected by ROV KIEL6000, from Plexauridae / Paramuricea ; AMPIV308-22 ; ZMH-K 60037 . GoogleMaps

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

Additional material

ICELAND – off Reykjanes • 1 spec., ethanol fixed; same data as for holotype; ZMH-K 58759 GoogleMaps • 3 specs, SEM-stubs; same data as for holotype; DZMB 61787 a-c GoogleMaps • 1 spec.; same data as for holotype; AMPIV312 -22; DZMB 62368 GoogleMaps • 1 spec.; same data as for holotype; AMPIV313 -22; DZMB 62369 GoogleMaps • 1 spec.; same data as for holotype; DZMB 61800 _d GoogleMaps • 1 spec.; same data as for holotype; AMPIV314 -22; DZMB-HH_62370 GoogleMaps • 1 spec.; same data as for holotype; AMPIV315 -22; DZMB-HH_62371 GoogleMaps • 3 specs.; Reykjanes Ridge; 59.24786°N, 30.488983°W; depth 869 m; 28 Jul. 2018; MSM75, IceAGE-RR exped., station 149-6; collected by ROV KIEL6000, from Plexauridae / Paramuricea ; ZMH-K 58760 GoogleMaps • 1 spec.; Reykjanes Ridge; 60.24765°N, 29.1379°W; depth 718 m; 13 Jul. 2018; MSM75, IceAGE-RR exped., station 67-6; collected by ROV KIEL6000, from Paragorgia arborea ; ZMH-K 58765 GoogleMaps • 1 spec.; same data as for preceding; ZMH-K 58767 GoogleMaps • 1 spec.; same data as for preceding; ZMH-K 58768 GoogleMaps • 1 spec.; same data as for preceding; ZMH-K 58769 GoogleMaps • 1 spec.; same data as for preceding; AMPIV304 -22; DZMB-HH 62314 GoogleMaps • 1 spec.; same data as for preceding; AMPIV301 -22; DZMB-HH 62311 GoogleMaps • 1 spec.; same data as for preceding; AMPIV302 -22; DZMB-HH 62312 GoogleMaps • 1 spec.; same data as for preceding; AMPIV305 -22; DZMB-HH 62315 GoogleMaps • 1 spec.; same data as for preceding; AMPIV306 -22; DZMB-HH 62316 GoogleMaps • 1 spec.; Reykjanes Ridge; 60.237°N, 29.136°W; depth 705 m; 1Aug. 2018; MSM75, IceAGE-RR exped., station 188-4; collected by ROV KIEL6000, from Paramuricea ; AMPIV320 -22; DZMB-HH_61711 GoogleMaps • 1 spec.; Reykjanes Ridge; 60.23625°N, 29.1288°W; depth 646 m; 1 Aug. 2018; MSM75, IceAGE-RR exped., station 188-5; collected by ROV KIEL6000, from Paramuricea ; AMPIV318 -22; DZMB 61715 GoogleMaps • 5 specs; same data as for preceding; DZMB 62851 _b GoogleMaps • 12 specs; same data as for preceding; DZMB 62852 _b. GoogleMaps

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. 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 View 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 .