3.1. Taxonomy
Asellota Latreille, 1802 [
39]
Superfamily Janiroidea G.O. Sars, 1897 [
40]
Family Munnopsidae Lilljeborg, 1864 [
6]
Subfamily Eurycopinae Hansen, 1916 [
12]
Genus
Eurycope G.O. Sars, 1864 [
13]
Type species:
Eurycope cornuta G.O. Sars, 1864 [
13]
Eurycope producta G.O. Sars, 1868 [
22] species complex
Diagnosis: Body ovoid; rostrum subequal in width and length to article 1 of antenna I, concave medially. Pereonites 1–4 subequal in medial length, longer than cephalon behind antennae I. Pereonite 7 longer than previous ones (medially), pereonites 5 and 6 subequal in length. Pleotelson about 0.3 times body length. Antenna I article 2 not longer than distomedial lobe of article 1; article 3 not shorter than article 2. Maxilliped palp subequal to basis in width; basis lateral projection near palp insertion acute, subequal in length to article 1. Epipod subequal to basis in length; tip narrow; lateral margin projected midlength. Pereopods V–VII dactylus length subequal to propodus width. Male pleopod I distolateral lobes weak, not longer than distomedial lobes. Male pleopod II distomedial margin with weak notch for exopod emerging. Uropod protopod and rami subequal in length; exopod about half of endopod width.
Description of characters common for all species of the complex: Body about twice as long as wide. Cephalon behind antennulae shorter than pereonite 1. Rostrum width about one third of cephalon width. Anterolateral margin of pereonites acute; coxae of pereopods I–IV visible in dorsal view, subequal in length and in shape, with acute anterior lobe and rounded posterior lobe. Pleotelson broader than long, about 0.3 times body length.
Antenna II squama of article 3 half as long as article 4.
Mandibular molar process distally truncate, denticulate; palp stout, subequal to mandibular body in length; article 3 slightly broader than article 2, twisted; distal seta longest.
Maxilla I mesial endite width about 0.7 times lateral endite width, with fine distal setae and one stout long distomedial seta; lateral endite with 12 robust differently serrated setae.
Maxilla II middle endite shortest, lateral endite longest; mesial endite with tuft of distal setae; distomedial setulated seta longest, middle and lateral endites with two long and two shorter comb-like distal setae.
Maxilliped basis length about three times width; endite width about half basis width; distal margin slightly concave, with several small fan setae and numerous fine small setae. Basis acute lateral projection near palp insertion subequal in length to lateral projection of article 1. Palp article 2 longest, equal in width to basis. Article 3 almost as wide as article 2; medial margin subequal in length to article 2, rounded. Article 4 equal to article 3 in lateral length; medial lobe subequal to article 5. Epipod length about twice width, 0.9 times basis length, width 1.3 times basis width tip narrow rounded, lateral margin projected midlength.
Bases of pereopods I–IV subequal in length, basis V shortest among all bases. Pereopod I broadest on basis–merus, dactylus < 0.3 times propodus length. Pereopods V–VII dactyli elongate, slightly bent, subequal in length to propodi; two setae proximal to claws, dorsal claw twice broader and longer than ventral one, two setae between claws. Pereopods V–VII carpi semirounded; propodi drop-like, broadened distally, about half as broad as carpi; dorsal margin serrated.
Male pleopod I and female pleopod II longer than branchial cavity of pleotelson, overlapping anterior part of anal. Male pleopod II protopod distolateral margin with several plumose setae; endopod and exopod inserted in middle of medial side, Pleopod III endopod with three or more plumose distal setae exopod with one distal seta. Pleopods V embraced laterally pleopods IV and III.
Uropod protopod cylindrical.
Remarks: The complex differs from all Eurycope species by having a broad and long rostrum, which is subequal in length and width to article 1 of antenna I. The combination of the other characters mentioned in the diagnosis distinguishes the species complex as well. The broad and long—almost rectangular—rostrum with lateral keels of the E. producta complex is similar to that of the genus Disconectes. Some species of Disconectes also have the pronounced distomedial lobes of male pleopod I. However, Disconectes differ in having the pereonites 5 and 6 dorsally fused, which are free in Eurycope.
As already noted by Svavarsson [
21],
E. gaussi from the Indian sector of the Southern Ocean and the two northwest Pacific species
E. linearis and
E. spinifrons are closely related species to the
E. producta complex. We may also include to the similar and related species
E. septentrionalis Malyutina and Kussakin, 1996 [
41] from the Canadian Basin of the North Polar Ocean as well as
E. andreyi Malyutina and Golovan, 2022 [
42]. All these mentioned species have a large rostrum, though not as notable as in the studied North Atlantic ones. All of them also possess similar morphological features to the male pleopods I and the maxillipeds. The North Pacific species differ from the studied species of the complex by a reduced distomedial lobe of antenna I article 1, which is shorter than article 2, in contrast to the long lobe of the species of the
E. producta complex.
3.2. Eurycope producta G.O. Sars 1868
Material examined:
Male (ZMH K-45596), 3.25 mm length; male (ZMH K-45592), 3.15 mm length, used for dissection; female (ZMH K-45583), 2.7 mm length; female (ZMH K-45584); and 12 further specimens (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum tapering distally, length 0.8 times basal width, basal width subequal to antenna I basal width. Maxilliped endite with three coupling hooks. Basis lateral projection near palp insertion length 1.2 times article 1 lateral length. Palp article 4 distomedial lobe length 0.75 times article 5 length. Epipod length 2.0 times width, 0.9 times basis length, width 1.3 times basis width. Male pleopod I length 2.3 times width, distal width 0.6 times basal width; distal margin rounded, lobes not separated. Male pleopod II protopod distomedial notch length 0.4 times medial margin length. Endopod of pleopod III with six plumose distal setae. Uropod protopod length 1.0 times width, endopod length 1.25 times protopod length, width 0.5 times protopod width; exopod length 0.95 times endopod length.
Description of male (ZMH K-45596,
Figure 3): Body length 1.95 times pereonite 5 width. Cephalon behind antennulae about half as long as pereonite 1; interantennular distance equal to antenna I basal width, 0.3 times cephalon width. Rostrum basal width subequal to length and antenna I basal width, reaching beyond tip of article 1 of antenna I, tapering distally; distal width 0.55 times basal width; middle groove deep. Pereonite 5 width 1.5 times pereonite 1 width; pereonite 7 posterior width 1.15 times pereonite 1 width. Natasome length 1.4 times anterior body part length. Pereonite 7 medial length 0.7 times pereonites 5 and 6’s combined medial length. Pleotelson length 0.8 times width, 0.3 times body length.
Antenna I (male, ZMH K-45592,
Figure 4A) broken off; article 1 length 1.25 times width, with five broom dorsal setae, one small UB seta laterally, and two UB setae distomedially. Article 2 length 1.3 times width, 0.4 times article 1 length, 0.85 times length of article 1 distomedial lobe, with three UB distal setae; articles 3 broken off.
Antenna II (male, ZMH K-45596,
Figure 3B) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Mandible (male, ZMH K-45592,
Figure 4B,C) incisors of both mandibles with four cusps;
lacinia mobilis of left mandible almost as long as incisor, with seven small distal teeth; spine row with eight and nine spines on left and right mandibles, respectively; molar process distally with six small setae on base of denticles. Palp length 1.1 times mandible body length; article 2 with row of small simple lateral setae and two stout setulated distal setae; articles 2 and 3 length 2.15 and 1.05 times article 1 length, respectively. Article 3 distal seta length 2.1 times other marginal setae length and 0.55 times article 3 length.
Maxilla I (male, ZMH K-45592,
Figure 5A) mesial endite width 0.75 times lateral endite width; lateral endite with five robust distolateral setae smooth other setae differently serrated.
Maxilla II (male, ZMH K-45592,
Figure 5B) middle endite shortest, lateral endite longest; mesial endite with tuft of distal setae, distomedial setulated seta longest, middle and lateral endites with two long and two shorter comb-like distal setae.
Maxilliped (male, ZMH K-45592,
Figure 5C) basis length 2.95 times width, lateral margin setulated; endite width 0.55 times basis width, with three coupling hooks; distal margin with five narrow fan setae. Basis acute lateral projection near palp insertion length 1.2 times article 1 lateral length. Palp length 2.25 times width, 0.75 times basis length. Article 2 length 0.8 times width, as wide as basis, lateral length 1.2 times medial length, each distal angle with small seta; article 3 almost as wide as article 2, medial length equal to article 2 medial length, lateral length 0.4 times article 2 lateral length, medial margin rounded, denticulate, few small setae distally; article 4 equal to article 3 in lateral length, medial lobe slightly shorter than article 5, with three long distal setae, article 5 with four long distal setae. Epipod length 2.0 times width, 0.9 times basis length, width 1.3 times basis width; tip narrow, with three setae.
Pereopod I (male, ZMH K-45592,
Figure 6C) as long as body, length ratios of ischium–dactylus to basis: 0.4, 0.3, 0.8, 0.65, 0.15. Basis length 7.1 times width, dorsal margin with nine small simple setae and one broom proximal seta, ventral margin with five small simple setae and three longer simple distoventral setae. Ischium length 4.0 times width, with three small simple distal setae. Merus with three simple distal setae. Carpus 0.6 times basis width, length 9.65 times width; with three dorsal and seven ventral simple setae. Propodus with six ventral simple setae and six distal simple setae; dactylus almost straight, claw length 0.4 times dactylus length.
Pereopod II (male, ZMH K-45592,
Figure 6D) length 1.9 times pereopod I length. Length ratios of ischium–dactylus to basis: 0.45, 0.4, 1.4, 1.7, 0.5. Basis stout, length 7.7 times width, with scattered small setae along basis, one broom dorsal seta and few distal setae. Ischium with two strong and five small simple ventral setae. Merus with five dorsal and five ventral simple setae. Carpus with 12 simple dorsal setae, seven small simple and 17 UB ventral setae; distal margin with one broom, one long and six small UB setae. Propodus with 17 simple dorsal setae, one broom seta, and one small UB seta distodorsally and 25 UB ventral setae. Dactylar claw length 0.25 times dactylus length.
Pereopod V (male, ZMH K-45592,
Figure 7A) propodus and dactylus broken off, length ratios of ischium–carpus to basis: 1.4, 0.6, 2.0. Basis length 1.8 times width, with one long whip and five broom dorsal setae and four small simple ventral setae. Ischium and merus visibly narrower than basis; ischium with eight plumose dorsal setae and three simple ventral setae. Merus with one dorsal plumose seta and five simple ventral setae. Carpus length 1.6 times width, with 24 dorsal and 18 ventral plumose setae, one broom, one UB, and three simple setae distally.
Pereopod VI (male, ZMH K-45592,
Figure 7B) propodus and dactylus broken off, length ratios of ischium–carpus to basis: 0.4, 0.5, 1.4. Basis length 2.7 times width, with three long distal setae. Ischium as wide as basis, with nine plumose dorsal setae and 14 simple ventral setae. Merus with one plumose dorsal seta and five simple ventral setae. Carpus length 1.5 times width, with 22 dorsal and 15 ventral plumose setae, one broom and three simple setae distoventrally.
Pereopod VII (male, ZMH K-45592,
Figure 7C) length ratios of ischium–dactylus to basis: 0.75, 0.45, 1.4, 1.3, 0.5. Basis length 2.5 times width, with one long proximodorsal seta and one distoventral simple seta. Ischium as wide as basis with six plumose dorsal setae and one distoventral broom seta. Merus with one plumose dorsal seta and five simple ventral setae. Carpus length 1.3 times width, with 20 dorsal and 14 ventral plumose setae. Propodus length 2.6 times width, with 15 dorsal and 14 ventral plumose setae, one small simple seta distoventrally, one broom seta and one stout long UB seta distodorsally; dactylus slender, spine-like al long as propodus width.
Pleopod I (male, ZMH K-45592,
Figure 8A) length 2.3 times basal width, distal width 0.6 times basal width. Distal margin slightly rounded; medial and lateral lobes not separated; distolateral angles with small setulae; seven longer ventral setae posteriorly distolateral lobes, distomedial rounded lobes with small setulae.
Pleopod II (male, ZMH K-45592,
Figure 8B,C) protopod length 1.65 times width, 0.9 times pleopod I length; distal margin with five simple setae, distomedial notch weak, length 0.4 times medial margin length. Stylet length 0.8 times protopod length, tip reaching behind pleopod I tip; sperm duct opening at 0.3 times length from proximal margin. Exopod distal article half as wide and 0.8 times as long as basal article.
Pleopod III (male, ZMH K-45592,
Figure 8D) protopod length 0.6 times width; endopod length 1.3 times width; three distal plumose setae length 0.4 times pleopod III length; exopod length 1.2 times protopod and endopod’s combined length, width 0.4 times width of endopod, with row of fine simple lateral setae; plumose distal seta subequal in length to endopod distal setae.
Pleopod IV (male, ZMH K-45592,
Figure 8E) endopod length 1.4 times width; exopod 0.85 times endopod length and 0.4 times endopod width; stout plumose distal seta as long as pleopod III distal setae.
Pleopod V (male, ZMH K-45592,
Figure 8F) length 1.45 times width, 1.2 times pleopod IV length.
Uropod (male, ZMH K-45592,
Figure 7D) length 0.3 times pleotelson length; protopod length 1.0 times width, with one UB distolateral seta and one broom seta and six UB distomedial setae. Endopod length 1.25 times protopod length, width 0.5 times protopod width, with four broom and seven UB distal setae and three simple medial setae. Exopod length 0.95 times endopod length, width 0.5 times endopod width, with seven UB and two broom distal setae.
Female (ZMH K-45583 and ZMH K-45584,
Figure 9A,B) habitus similar to that of male.
Pleopod II (female, ZMH K-45583,
Figure 9C) length 0.8 times width, proximolateral margin with one simple setae; distomedial margin rounded, pronounced, overlapping anterior part of anal operculum; distolateral margin with row of simple setae. Ventral keel length 0.7 times pleopod II length with strong UB seta posteriorly.
Remarks: Our specimens were identified as
E. producta G.O. Sars, 1868 sensu stricto as they fit the original descriptions and illustrations in G.O. Sars [
43], though the male pleopod I in Sars’s Pl. 65 has more pronounced distomedial lobes than our specimens.
Distribution:Eurycope producta occurs according to G.O. Sars [
43] along the Norwegian coast from Christiania Fjord (Oslo), Skagerrak in the South to Vadsø in the North at a depth range of 60–400 fathoms (109.7–731.5 m). The species was recorded in many further publications west of Ireland, off the Faroe Islands, south of Iceland, near eastern, southern and southwestern Greenland, and in the southern part of the Davis Strait, featuring a depth range of 72–2087 m [
44] (pp. 56–59). The herein-studied specimens of
E. producta sensu stricto were sampled in the Denmark Strait, the Norwegian Sea, the Iceland–Faroe Ridge, and the Iceland Basin, featuring a depth range of 316–1385 m.
3.3. Eurycope dahli Svavarsson, 1987
Material examined:
Male (ZMH K-45598), 5.7 mm length; male (ZMH K-45609), used for dissection; female (ZMH K-45612), 4.6 mm length; juvenile (ZMH K-45606); and 19 further specimens (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum not tapering distally length 1.0 times basal width, 0.8 times antenna I article I length, basal width 0.75 times antenna I width. Maxilliped endite with four coupling hooks. Basis lateral projection near palp insertion length 1.2 times article 1 lateral length. Palp article 2 length 1.05 times width, width 0.85 times basis width. Article 4 distomedial lobe length 0.8 times article 5 length. Epipod length 2.2 times width, 0.85 times basis length, width 1.2 times basis width. Male pleopod I length 2.7 times basal width, width 0.5 times basal width, distal margin straight, lobes not separated. Male pleopod II protopod distomedial notch length 0.3 times medial margin length. Endopod of pleopod III with six plumose distal setae. Uropod protopod length 1.0 times width; endopod length 1.35 times protopod length, width 0.35 times protopod width; exopod length 0.95 times endopod length.
Description of male (ZMH K-45598,
Figure 10A–C): Body length 2.1 times pereonite 5 width. Cephalon behind antennulae slightly shorter than pereonite 1; interantennular distance 0.65 times antenna I basal width, 0.25 times cephalon width. Rostrum length 1.0 times basal width, 0.8 times antenna I article I length, not reaching tip of article 1 of antenna I, longitudinal groove deep. Pereonites 1–4 subequal in medial length. Pereonite 5 width 1.75 times pereonite 1 width; pereonite 7 posterior width 1.3 times pereonite 1 width. Natasome length 2.0 times anterior body part length. Pereonites 5 and 6 of same length; pereonite 7 longest; medial length 0.8 times pereonites 5 and 6’s combined medial length. Ventral projection of pereonites 6–7 0.35 times body length. Pleotelson length 0.9 times width, 0.35 times body length.
Antenna I (male, ZMH K-45609,
Figure 11A) broken off on article 3; article 1 length 1.15 times width with two distal and two dorsal broom setae; article 2 length 0.35 times article 1 length, not reaching tip of distomedial lobe of article 1, with one distal broom seta; article 3 broken, width 0.4 times article 2 width.
Antenna II (male, ZMH K-45598,
Figure 12A) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Mandible (male, ZMH K-45609,
Figure 12B) incisors of left mandible with six cusps, lacinia mobilis almost as long as incisor, with seven distal teeth; spine row with 11 spines; molar process distodorsally acute, with 11 small setae on base of denticles; condyle length 0.15 times mandibular body length. Palp length 1.05 times mandibular body length; article 2 with nine thin medial setae and one long distal seta; articles 2 and 3’s lengths 2.1 times and 0.85 times article 1 length, respectively. Article 3 distal seta length 3.5 times other marginal setae length and as long as article 3.
Maxilla I (male, ZMH K-45609,
Figure 11B) mesial endite width 0.7 times lateral endite width, with fine distal setae, and one stout long distomedial seta; lateral endite with 12 robust setae, four distolateral setae smooth—other setae differently serrated.
Maxilla II (male, ZMH K-45609,
Figure 11C) mesial and lateral endites subequal in length, middle endite shortest; mesial endite with tuft of distal setae, one long setulated seta distomedially, middle and lateral endites with two long and two shorter comb-like distal setae.
Maxilliped (male, ZMH K-45609,
Figure 11D) basis length 2.85 times width; endite width 0.55 times basis width, with four coupling hooks, distal margin slightly concave, with six small fan setae. Basis acute lateral projection near palp insertion length 1.2 times article 1 lateral length. Palp length 2.6 times width, 0.75 times basis length. Article 2 length 1.05 times width, width 0.85 times basis width, lateral length 1.4 times medial length. Article 3 almost equal to article 2 in width and medial length, lateral length 0.3 times article 2 lateral length; medial margin rounded, denticulate, with small setae. Article 4 lateral length 1.45 times article 3 lateral length, medial lobe slightly shorter that article 5, with six long distal setae. Article 5 as long as article 4 laterally, with seven long distal setae. Epipod length 2.2 times width, 0.85 times basis length, width 1.2 times basis width.
Pereopods broken off.
Pleopod I (male, ZMH K-45609,
Figure 13A) length 2.7 times basal width, distal width 0.5 times basal width, distal margin straight, medial and lateral lobes not separated, distolateral and distomedial angles with small setulae, each lobe with seven small ventral setae subdistally.
Pleopod II (male, ZMH K-45609,
Figure 13B) protopod length 1.6 times width, 0.9 times pleopod I length; distal margin with eight simple setae, distomedial notch well defined, length 0.3 times medial margin length. Stylet length 0.7 times protopod length, tip reaching slightly behind pleopod II tip; sperm duct opening at 0.4 times length from proximal margin. Exopod distal article half as wide and almost as long as basal article.
Pleopod III (male, ZMH K-45609,
Figure 13C) protopod length 0.45 times width, endopod length 1.3 times width; six plumose setae distally, length 0.35 times pleopod III length; exopod subequal in length to protopod and endopod together, width 0.3 times endopod width, with row of fine simple marginal setae, plumose seta distally, length slightly longer than endopod distal setae length.
Pleopod IV (male, ZMH K-45609,
Figure 13D) endopod length 1.4 times width; exopod 0.9 times endopod length and 0.6 times endopod width. Stout plumose distal seta length 1.2 times distal seta of pleopod III exopod length.
Pleopod V (male, ZMH K-45609,
Figure 13E) length 1.2 times width.
Uropod (male, ZMH K-45609,
Figure 12C) length 0.25 times pleotelson length; protopod cylindrical, length 1.0 times width, with four UB and three simple distal setae. Endopod length 1.35 times protopod length, width 0.4 times protopod width, with four broom and six UB distal setae. Exopod length 0.95 times endopod length, width 0.5 times endopod width, with one broom and three UB distal setae.
Female (ZMH K-45612,
Figure 10D) habitus is similar to male.
Antenna I (female, ZMH K-45612,
Figure 10D) article 1 length 1.1 times width, distomedial lobe reaching beyond tip of article 2. Article 2 length 0.45 times article 1 length, 0.8 times distomedial lobe of article 1 length. Articles 3 length 1.4 times article 2 length; articles 3–5 width 0.75 times article 2 width; articles 4 and 5 subequal in width. Tip of flagellum broken off.
Pleopod II (female, ZMH K-45612,
Figure 10E) length 1.2 times width; distomedial margin overlapping anterior part of anal operculum; ventral keel length 0.7 times pleopod II length.
Remarks: The species differs from other species of the complex by its rostrum, which is shorter (0.8 times) than antenna I article I (in all other species the rostrum is equal in length or longer than antenna I article I) and narrower (0.75 times) than antenna I article I. It is the only species of the complex which has six distal plumose setae on the endopod of pleopod III (all others have only three setae).
Distribution: The Greenland Sea (2470–3709 m), the Norwegian Sea (2085–3672 m), and the North Polar Basin (81°40′N 2°602′E 2400–2500 m). The studied specimens of E. dahli were sampled in the Norwegian Sea, featuring a depth range of 2203–2373 m depth.
3.4. Eurycope mishkai Malyutina & Schnurr sp. nov.
Paratypes: female (ZMH K-45626), 3.1 mm length; female (ZMH K-45625), used for dissection; male (ZMH K-45624), used for dissection; and 2 further specimens (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum tapering distally, length 1.0 times basal width basal width subequal to antenna I basal width, longitudinal groove deep. Maxilliped endite with three coupling hooks. Basis lateral projection near palp insertion as long as article 1. Article 4 distomedial lobe length 1.25 times article 5 length. Epipod length 2.35 times width, 0.95 times basis length, width 1.2 times basis width. Epipod length 2.1 times width, 0.9 times basis length, width 1.35 times basis width. Pleopod I length 4.0 times basal width; distal margin straight, its width 0.5 times basal width; medial and lateral lobes not separated. Male pleopod II protopod distomedial notch length 0.4 times medial margin length. Uropod protopod length 1.0 times width; endopod length 1.25 times protopod length, width 0.5 times protopod width; exopod length 0.95 times endopod length.
Description of male (holotype, ZMH K-45621,
Figure 14A–D): Body length 2.2 times pereonite 5 width. Cephalon interantennular distance subequal to antenna I basal width, 0.3 times cephalon width. Rostrum length 1.0 times basal width, slightly reaching behind tip of article 1 of antenna I; longitudinal groove deep. Pereonite 5 width 1.5 times pereonite 1 width; pereonite 7 posterior width 1.2 times pereonite 1 width. Natasome length 2.3 times anterior body part length. Pereonites 5–7 subequal in lateral length; medially, pereonites 5 shortest; pereonite 6 slightly longer; pereonite 7 longest. Pereonite 7 medial length 0.6 times pereonites 5 and 6’s combined medial length. Pleotelson length 0.65 times width, 0.25 times body length.
Antenna I (male paratype, ZMH K-45624,
Figure 15A) article 1 length 1.3 times width, with one small UB distomedial seta. Article 2 length 0.3 times article 1 length, 0.7 times distomedial lobe of article 1 length, with two distal broom setae. Articles 3 and 4 lengths 1.0 times and 0.2 times article 2 length, respectively; article 3 width 0.75 times article 2 width. Flagellum broken off.
Antenna II (male holotype, ZMH K-45621,
Figure 14A,C) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Mandible (male paratype, ZMH K-45624,
Figure 15B) incisors of left mandible with four cusps; lacinia mobilis almost as long as incisor, with four distal teeth; spine row with eight spines; molar process distodorsal margin acute, with four small setae on base of denticles; condyle length 0.15 times mandibular body length. Palp length 0.85 times mandibular body length; article 2 with two long distal setae; articles 2 and 3 lengths 1.95 times and 0.95 times article 1 length, respectively. Article 3 distal seta length 1.65 times other marginal setae and 0.85 times article 3 length.
Maxilla I (male paratype, ZMH K-45624,
Figure 15C) mesial endite width 0.7 times lateral endite width, with fine distal setae and one stout long distomedial seta; lateral endite with 12 robust setae, four distolateral setae smooth other setae differently serrated.
Maxilla II (male paratype, ZMH K-45624,
Figure 15D) mesial and lateral endites subequal in length, middle endite shortest; mesial endite with tuft of distal setae, one long setulated seta distomedially, middle and lateral endites with two long and two shorter comb-like distal setae.
Maxilliped (male paratype, ZMH K-45624,
Figure 15E) basis length 2.9 times width; endite width 0.5 times basis width, with three coupling hooks; distal margin slightly concave, with five small fan setae and numerous fine small setae. Basis acute lateral projection near palp insertion as long as article 1. Palp length 2.0 times width, 0.7 times basis length. Article 2 length 0.85 times width, as wide as basis; lateral length 1.05 times medial length. Article 3 almost equal to article 2 in width; medial length 0.7 times medial length of article 2; medial margin rounded, denticulate, with small setae; lateral length 0.3 times article 2 lateral length. Article 4 lateral length equal to article 3 lateral length; medial lobe length 1.1 times article 5 length, with three long distal setae; article 5 with three long distal setae. Epipod length 2.35 times width, 0.95 times basis length, width 1.2 times basis width.
Pereopods broken off.
Pleopod I (male paratype, ZMH K-45624,
Figure 16A) length 2.5 times basal width, distal width 0.5 times basal width; distal margin truncated; medial and lateral lobes not separated. Distolateral and distomedial angles with small setulae.
Pleopod II (male paratype, ZMH K-45624,
Figure 16B) Protopod length 1.5 times width, 0.75 times pleopod I length, distomedial weak notch 0.4 times protopod length, distal margin with few simple setae. Stylet length 0.85 times protopod length, tip reaching behind protopod tip; sperm duct opening at 0.35 times length from proximal margin. Exopod distal article half as wide and almost as long as basal article; small setae on outer angle of hook.
Pleopod III (male paratype, ZMH K-45624,
Figure 16C) protopod length 0.65 times width; endopod length 1.3 times width, distal margin truncated, width 1.2 times proximal width, with three distal plumose setae, setae length 0.3 times pleopod III length. Exopod subequal in length to protopod and endopod together, width 0.3 times endopod width, with row of fine simple lateral setae; length of thin simple distal seta subequal to endopod distal setae length.
Pleopod IV (male paratype, ZMH K-45624,
Figure 16D) endopod length 2.1 times width; exopod length 0.9 times endopod length and 0.8 times endopod width. Stout plumose distal seta length 0.6 times exopod length and 1.7 times pleopod III distal setae length.
Pleopod V (male paratype, ZMH K-45624,
Figure 16E) length 1.7 times width.
Female (female paratype, ZMH K-45626,
Figure 14E) habitus similar to male, length 2.0 times width; natasome broader than in male. Cephalon interantennular distance 0.9 times antenna I basal width, 0.25 times cephalon width. Rostrum length 1.15 times basal width.
Uropod (female paratype, ZMH K-45625,
Figure 14F) length 0.15 times pleotelson length; protopod cylindrical, length 1.0 times width, with one lateral and five UB distal setae. Endopod length 1.25 times protopod length, width 0.5 times protopod width, with one simple and six UB distal setae; exopod length 0.95 times endopod length, width 0.5 times endopod width, with three UB distal setae.
Etymology: The name honors Marina Malyutina’s son, Mikhail Malyutin (Mishka is a child nickname).
Distribution: Known only in the type locality in the Denmark Strait at a depth of 1249 m.
3.5. Eurycope nikitai Malyutina & Schnurr sp. nov.
Paratypes: female (ZMH K-45629), 3.8 mm length; male (ZMH K-45633); male (ZMH K-45630), used for dissection; and five further specimens (see
Table 1 for specimen information).
Diagnosis: Pereonites 5–7 equal in medial length. Cephalon rostrum length 1.0 times basal width, subequal to antenna I basal width. Maxilliped endite with two coupling hooks. Basis lateral projection near palp insertion as long as article 1. Article 4 medial lobe length 0.6 times article 5 length. Epipod length 2.1 times width, 0.9 times basis length, width 1.35 times basis width. Pleopod I length 2.8 times basal width; distal margin with light rounded notch between distomedial and distolateral lobes. Male pleopod II protopod distomedial notch length 0.25 times medial margin length. Uropod protopod length 0.95 times width; endopod length 1.3 times protopod length, width 0.75 times protopod width; exopod as long as endopod.
Description of male (holotype, ZMH K-45627,
Figure 17A–C): Body length 2.0 times pereonite 5 width. Cephalon behind antennulae slightly shorter than pereonite 1; interantennular distance 1.35 times antenna I basal width, 0.45 times cephalon width. Rostrum length 0.75 times basal width, reaching tip of article 1 of antenna I; distal width 0.35 times basal width; medial groove small. Ambulosome: pereonites 2 longest, pereonites 1, 3 and 4 subequal in medial length. Natasome length 1.8 times anterior body part length. Pereonite 5 width 1.4 times pereonite 1 width; pereonite 7 posterior width 1.2 times pereonite 1 width. Pereonites 5–7 subequal in medial length, pereonite 7 shortest laterally. Pleotelson length 0.8 times width, 0.35 times body length.
Antenna I (male paratype, ZMH K-45633,
Figure 18A) article 1 length 1.0 times width, with one broom dorsal seta, one UB seta and one simple seta distomedially. Article 2 length 0.45 times article 1 length, reaching tip of distomedial lobe of article, with two broom and two simple distal setae. Article 3 and flagellum broken off.
Antenna II (male holotype, ZMH K-45627,
Figure 17A,B) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Antenna II (male paratype, ZMH K-45633,
Figure 17E) twice longer than BL; article 5 length 0.5 times total body length, article 6 1.2 times article 5 length and slightly narrower than article 5; flagellum length 0.7 times peduncle length.
Mandible (male paratype, ZMH K-45633,
Figure 18B) incisors of right mandible with four cusps, spine row with eight spines, molar process with two small distal setae on base of denticles; condyle length 0.15 times mandibular body length. Palp length 1.05 times mandible body length; article 2 with two distal setae; articles 2 and 3 lengths 1.85 times and 0.95 times article 1 length, respectively. Article 3 distal seta length 1.65 times other marginal setae and 0.5 times article 3 length.
Maxilla I (male paratype, ZMH K-45633,
Figure 18C) mesial endite width 0.65 times lateral endite width, with fine distal setae and one stout long distomedial seta; lateral endite with 12 robust distolateral setae differently serrated.
Maxilla II (male paratype, ZMH K-45633,
Figure 18D) middle endite visibly shorter than mesial and lateral endites which subequal in length; mesial endite with row of distal setae, middle and lateral endites with two long and two shorter distal setae.
Maxilliped (male paratype, ZMH K-45633,
Figure 18E) basis length 3.1 times width; endite width 0.5 times basis width, with two coupling hooks, distal margin narrow, straight, with one small fan seta. Basis acute lateral projection near palp insertion as long as article 1 laterally. Palp length 2.25 times width, 0.7 times basis length. Article 2 length 0.9 times width, as wide as basis; lateral length 1.15 times medial length; one long distomedial seta. Article 3 almost equal to article 2 in width; medial length 0.9 times article 2 medial length, lateral length 0.35 times article 2 lateral length; medial margin rounded, denticulate, with small setae. Articles 4 and 5 lateral lengths 1.2 times and 1.4 times article 3 lateral length, respectively, medial lobe slightly shorter than article 5, with three simple distal setae; article 5 with three simple distal setae. Epipod length 2.1 times width, 0.9 times basis length, width 1.35 times basis width.
Pereopod I (male paratype, ZMH K-45633,
Figure 19A) length 0.75 times body length, length ratios of ischium–dactylus to basis: 0.3, 0.25, 0.9, 0.75, 0.25. Carpus 0.6 times width of basis, length 10.2 times width; nine UB setae ventrally. Propodus with three ventral simple setae and four simple distal setae. Dactylus almost straight, claw length 0.4 times dactylus length.
Pereopod II (male paratype, ZMH K-45633,
Figure 19B) broken off after carpus. Basis–carpus length 0.75 times body length, length ratios of ischium–carpus to basis: 0.45, 0.3, and 1.3. Basis stout, length 5.2 times width with five small dorsal and two distal setae. Carpus length 10.7 times width with 14 ventral and three distal UB setae.
Pereopod V (male paratype, ZMH K-45633,
Figure 19C) length ratios of ischium–dactylus to basis: 1.75, 0.75, 2.35, 2.2, 1.1. Basis length 1.3 times width, with one long plumose and two small simple dorsal setae. Ischium slightly narrower than basis, with three dorsal plumose setae. Merus with one dorsal and one ventral long simple setae. Carpus length 1.4 times width, with 12 dorsal and 10 ventral plumose setae, one stout UB seta and two long simple setae distodorsally. Propodus length 2.1 times width, dorsal margin serrated with nine plumose setae ventral margin with 10 plumose setae, one stout UB seta and one broom seta distodorsally. Dactylar dorsal claw twice longer than slim ventral claw.
Pereopod VII (male paratype, ZMH K-45633,
Figure 19D) length 0.7 times pereopod V length, length ratios of ischium–dactylus to basis: 0.9, 0.5, 1.6, 1.4, 0.7. Basis length 2.1 times width; ischium as broad as basis, with four dorsal plumose setae; merus with one plumose dorsal seta. Carpus length 1.35 times width, with 10 dorsal and eight ventral plumose setae. Propodus length 2.35 times width, dorsal margin serrated with six plumose setae; ventral margin with eight plumose setae and one stout UB seta, one broom seta distodorsally. Dactylar dorsal claw three times longer than tiny ventral claw.
Pleopod I (male paratype, ZMH K-45633,
Figure 20A) length 2.7 times basal width, distal width 0.7 times basal width; distal margin almost straight; lateral lobes slightly longer than medial; distomedial lobes with four small setulae each.
Pleopod II (male paratype, ZMH K-45633,
Figure 20B) protopod length 1.5 times width, subequal to pleopod I length; distal margin with few simple setae; distomedial notch length 0.25 times medial margin length. Stylet length 0.45 times protopod length, tip not reaching pleopod I tip. Exopod distal article half as wide and almost as long as basal article.
Pleopod III (male paratype, ZMH K-45633,
Figure 20C) protopod length 0.65 times width; endopod length 1.4 times width; three distal plumose setae length 0.7 times pleopod III length; exopod subequal in length to protopod and endopod together and 0.3 times width of endopod, with row of fine simple lateral setae; distal seta simple, thin, its length 0.3 times endopod distal setae length.
Pleopod IV (male paratype, ZMH K-45633,
Figure 20D) endopod length 1.2 times width, exopod 0.8 times endopod length and 0.5 times endopod width. Stout plumose distal seta as long as exopod.
Pleopod V (male paratype, ZMH K-45633,
Figure 20E) length 1.2 times width, 1.15 times pleopod IV length.
Uropod (male paratype, ZMH K-45633,
Figure 19E) length 0.3 times pleotelson length; protopod broadening distally, length 0.95 times width, with two simple and six UB distal setae. Endopod length 1.3 times protopod length, width 0.5 times protopod width, with one simple, one broom, and four UB distal setae; exopod as long as endopod, width 0.5 times endopod width, with one broom and two UB distal setae.
Female (paratype, ZMH K-45629,
Figure 21) habitus is similar to male, length 1.9 times width. Cephalon behind antennulae half as long as pereonite 1; interantennular distance 1.5 of antenna I basal width, 0.4 times cephalon width. Rostrum length 0.8 times basal width, apical width 0.4 times basal width, with small medial groove. In ambulosome pereonites 2–4 subequal in medial length. Pereonite 5 width 1.7 times pereonite 1 width; pereonite 7 posterior width 1.4 times pereonite 1 width.
Antenna I (female paratype, ZMH K-45629,
Figure 21A,B) article 1 length 1.1 times width; distomedial lobe reaching midlength of article 2 with small distal seta. Article 2 length 1.15 times width, with two broom long distal setae; articles 3–5 lengths 1.05, 0.2, and 0.55 times article 2 length, respectively; articles 3–5 widths 0.75 times article 2 width; articles 4 and 5 subequal in width, 0.5 times article 2 width. Flagellum broken off.
Pleopod II (female paratype, ZMH K-45629,
Figure 21C,D) length 0.9 times width; margins with few small simple setae, distomedial margin rounded, pronounced, overlapping anterior part of anal operculum, with 12 small simple setae; ventral keel length 0.7 times pleopod II length, long UB seta on tip.
Etymology: The name honors Marina Malyutina’s eldest grandson, Nikita Malyutin.
Distribution: Known only from the Iceland Basin, featuring a depth range of 2568–2750 m.
3.6. Eurycope gordeyi Malyutina & Schnurr sp. nov.
Paratypes: male (ZMH K-45646), 2.9 mm length, used for dissection; male (ZMH K-45645), used for dissection; female (ZMH K-45651), 2.55 mm length; female (ZMH K-45638); and 11 further specimens (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum length 1.1 times basal width, 1.2 times article 1 of antenna I length; width 1.2 times antenna I basal width. Maxilliped endite with five coupling hooks. Basis lateral projection near palp insertion length 0.9 times article 1 lateral length. Palp article 2 length 1.2 times width, article 4 medial lobe as long as article 5. Epipod length 2.5 times width, 0.95 times basis length; width 1.2 times basis width. Pleopod I length 3.25 times basal width, distomedial lobe length 0.05 times pleopod I length, width 0.3 times pleopod I basal width; distolateral lobes tiny, acute, slightly projected. Male pleopod II protopod distomedial notch length 0.35 times medial margin length. Uropod protopod length 1.15 width; endopod length 0.9 times protopod length, width 0.75 times protopod width; exopod length 0.85 times endopod length.
Description of male (holotype, ZMH K-45636,
Figure 22A–C): Body length 1.85 times pereonite 5 width. Cephalon behind antennulae slightly shorter than pereonite 1; rostrum width subequal to antenna I basal width, 0.3 times cephalon width. Rostrum length 1.25 times basal width, 1.2 times antenna I article I length; medial groove deep, margins with small simple setae distally. Pereonite 5 width 1.6 times pereonite 1 width; pereonite 7 posterior width 1.35 times pereonite 1 width. Natasome length 2.1 times anterior body part length. Pereonites 5–7 subequal in lateral length; medially, pereonites 5 and 6 subequal in length; pereonite 7 longest, 0.6 times pereonites 5 and 6’s combined medial length. Pleotelson length 0.7 times width, 0.3 times body length.
Antenna I (male paratype, ZMH K-45646,
Figure 23A) article 1 length 1.0 times width, with three broom dorsal setae, distomedial lobe with two broom and two small UB setae. Article 2 length 1.05 times width, 0.85 times distomedial lobe of article 1 length, with three broom and three UB distal setae. Articles 3–5 subequal in width, 0.7 times article 2 width; lengths 0.9, 0.3, and 0.5 times article 2 length, respectively. Article 4 with one distal broom UB seta. Flagellum broken off after nine articles, last articles with eastetascs.
Antenna II (male holotype, ZMH K-45636,
Figure 22B) articles 1–6 length 0.75 times body length. Squama on article 3 reaching midlength of article 4. Article 6 1.1 times article 5 length and slightly narrower than article 5, flagellum broken off.
Left mandible (male paratype, ZMH K-45646,
Figure 23B) incisor and lacinia mobilis with five cusps; spine row with nine spines; molar process distodorsally acute, with four thin setae on base of denticles. Condyle length 0.2 times mandibular body length. Palp length subequal to mandible body length; article 2 with three small simple lateral setae and three strong serrated distal setae; articles 2 and 3 lengths 2.2 times and 1.1 times article 1 length, respectively. Article 3 distal seta length 2.65 times other marginal setae length and 0.8 times article 3 length.
Maxilla I (male paratype, ZMH K-45645,
Figure 23C) mesial endite width 0.6 times lateral endite width.
Maxilla II (male paratype, ZMH K-45645,
Figure 23D) middle endite shortest, lateral endite slightly longer than mesial endite.
Maxilliped (male paratype, ZMH K-45645,
Figure 23E) basis length 3.2 times width; endite width 0.5 times basis width, with five coupling hooks; distal margin with four fan setae. Basis acute lateral projection near palp insertion length 0.9 times article 1 lateral length. Palp length 2.2 times width, 0.7 times basis length. Article 2 length 1.2 times width, width 1.05 times basis width; lateral length 1.1 times medial length; two small setae distolaterally. Article 3 width 0.8 times article 2 width; medial length 0.8 times article 2 medial length; lateral length 0.35 times article 2 lateral length; medial margin denticulate, with seven small setae. Article 4 equal to article 3 in lateral length; medial lobe slightly shorter than article 5, with three distal setae. Article 5 with five long distal setae. Epipod length 2.5 times width, 0.95 times basis length; width 1.2 times basis width, tip narrow and rounded with one small simple seta.
Pereopods broken off after bases (male holotype, ZMH K-45636,
Figure 22B,C); bases I–IV of same length—0.25 times body length.
Pleopod I (male paratype, ZMH K-45645,
Figure 24A) length 2.3 times basal width; distal margin narrow, width 0.3 times basal width; medial lobes projected, rounded, length 0.05 times total pleopod length, with 12 small setae each; lateral lobes projected in small acute lateral angles, with small setae proximally.
Pleopod II (male paratype, ZMH K-45645,
Figure 24B) protopod length 1.6 times width, 0.9 times pleopod I length; distal margin with five simple setae; distomedial notch length 0.35 times medial margin length. Stylet length 0.7 times protopod length, tip reaching protopod tip; sperm duct opening at 0.55 times length from proximal margin. Exopod distal article width 0.6 times basal article width, both articles subequal in length.
Pleopod III (male paratype, ZMH K-45646,
Figure 24C) protopod length 0.65 times width; endopod length 1.25 times width; three distal plumose setae length 0.35 times pleopod III total length; exopod as long as protopod and endopod together, reaching endopod tip, width 0.3 times endopod width, with row of fine simple lateral setae; distal seta simple, thin, length 0.8 times endopod distal setae length.
Pleopod IV (male paratype, ZMH K-45646,
Figure 24D) endopod length 1.35 times width, exopod as long as endopod, width 0.45 times endopod width. Stout plumose distal seta length 0.7 times exopod length.
Pleopod V (male paratype, ZMH K-45646,
Figure 24E) length 1.2 times width.
Uropod (male paratype, ZMH K-45645,
Figure 22D) length 0.15 times pleotelson length; protopod length 1.15 times width, with four UB, eight whip, and two simple distal setae. Endopod length 0.9 times protopod length, width 0.5 times protopod width, with one broom, one simple, and 14 UB distal setae; exopod length 0.85 times endopod length, width 0.5 times endopod width, with five UB distal setae.
Female (paratype, ZMH K-45651,
Figure 25B–D) habitus length 1.75 times width. Cephalon behind antennulae length 0.3 times pereonite 1 length; interantennular distance 0.8 times antenna I basal width, 0.35 times cephalon width. Rostrum length 1.0 times basal width. Pereonite 5 width 1.6 times pereonite 1 width; pereonite 7 posterior width 1.3 times pereonite 1 width. Natasome length 1.95 times anterior body part length. Pereonite 7 medial length 0.7 times pereonites 5 and 6’s combined medial length. Pleotelson length 0.5 times width, 0.2 times body length.
Pleopod II (female paratype, ZMH K-45638,
Figure 25E) length 0.65 times width; lateral margin with two small simple setae; distomedial margin rounded, pronounced, overlapping anterior part of anal operculum.
Etymology: The name honors Marina Malyutina’s youngest grandson, Gordey Malyutin.
Distribution: Known only from the type locality in the Norwegian Channel and the Iceland–Faroe Ridge, featuring a depth range of 441–1058 m.
3.7. Eurycope emmae Schnurr & Malyutina sp. nov.
Paratypes: female (ZMH K-45653), 2.6 mm length; female (ZMH K-45655), used for dissection; male (ZMH K-45654), used for dissection (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum length 0.85 times basal width, 1.5 times antenna I article 1 length, 1.7 times antenna I article 1 width. Maxilliped endite with two coupling hooks. Basis lateral projection near palp insertion length 0.9 times article 1 lateral length. Palp article 4 medial lobe subequal in length to article 5. Epipod length 2.4 times width, 0.95 times basis length; width 1.2 times basis width. Male pleopod I length 2.4 times width; distomedial lobe length 0.05 times pleopod I length, width 0.25 times pleopod I width, distolateral lobes slightly projected. Male pleopod II protopod distomedial notch length 0.3 times medial margin length. Uropod protopod length 1.0 times width; endopod length 1.05 times protopod length, width 0.75 times protopod width; exopod length 1.0 times endopod length.
Description of male (holotype, ZMH K-45652,
Figure 26A,B): Body length 1.7 times pereonite 5 width. Cephalon behind antennulae almost hidden under pereonite 1. Rostrum length 0.85 times basal width, 1.5 times antenna I article 1 length; width 0.3 times cephalon width, 1.7 times antenna I article 1 width; medial groove small. Pereonite 5 width 1.8 times pereonite 1 width; pereonite 7 posterior width 1.5 times pereonite 1 width. Natasome length 4.0 times anterior body part length; pereonite 7 longest medially, length 0.7 times pereonites 5 and 6’s combined medial length. Pleotelson length 0.5 times width, 0.25 times body length.
Antenna I (male holotype, ZMH K-45652,
Figure 26A): article 1 length 1.0 times width; article 2 length 0.6 times article 1 length, as long as distomedial lobe of article 1. Articles 3 and 4 lengths 1.0 times and 0.25 times article 2 length, respectively; articles 3 and 4 widths 0.8 times article 2 width. Flagellum broken off after article 6.
Antenna II (male holotype, ZMH K-45652,
Figure 26A,B) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4, with long distal seta.
Mandible (male paratype, ZMH K-45654,
Figure 27B,C) incisor with five and four cusps and spine row with nine and eight spines on right and left mandibles, respectively; lacinia mobilis of left mandible slightly shorter than incisor, with four distal teeth. Molar process distodorsally acute, with two thin setae on base of denticles. Palp length subequal to mandible body length; article 2 with three distal setae; articles 2 and 3 lengths 2.2 times and 1.1 times article 1 length, respectively. Article 3 distal seta length 1.45 times other marginal setae length and 0.5 times article 3 length.
Maxilla I (male paratype, ZMH K-45654,
Figure 28A) mesial endite width 0.6 times lateral endite width, with fine distal setae and two long distomedial setae; lateral endite with 12 robust differently serrated setae.
Maxilla II (male paratype, ZMH K-45654,
Figure 28B) middle endite shortest, lateral endite longest; mesial endite with tuft of distal setae, middle and lateral endites with two long and two shorter distal setae.
Maxilliped (male paratype, ZMH K-45654,
Figure 28C) basis length 3.0 times width; endite width 0.5 times basis width, with two coupling hooks; distal margin with three fan setae. Basis acute lateral projection near palp insertion length 0.9 times article 1 lateral length. Palp length 2.2 times width, 0.95 times basis length. Article 2 length 0.95 times width, slightly wider than basis; lateral length 1.1 times medial length, one small distolateral seta. Article 3 width 0.9 times article 2 width; medial length 0.85 times article 2 medial length; lateral length 0.3 times article 2 lateral length; medial margin denticulate, with few small setae. Article 4 lateral length 1.35 times article 3 lateral length; medial lobe as long as article 5, with four setae. Article 5 with two lateral and three distal setae. Epipod length 2.4 times width, 0.95 times basis length; width 1.2 times basis width.
Pereopod V (male holotype, ZMH K-45652,
Figure 29A) length ratios of ischium–dactylus to basis: 1.0, 0.6, 1.7, 1.5, 0.7. Basis length 1.7 times width, with one long plumose distodorsal and two simple dorsal setae and one UB distoventral seta. Ischium as long and as wide as basis, with seven plumose dorsal setae and four distoventral setae. Merus with four ventral UB and five simple distoventral setae. Carpus length 1.35 times width, with 20 dorsal and 10 ventral plumose setae; four stout UB setae distodorsally. Propodus length 1.85 times width; dorsal margin serrated with nine plumose setae ventral margin with 18 plumose setae, one stout UB seta, and one broom seta distodorsally. Dactylar dorsal claw length 0.3 times slim ventral claw length.
Pereopod VII (male holotype, ZMH K-45652,
Figure 29B) length 0.7 times pereopod V length; length ratios of ischium–dactylus to basis: 0.65, 0.4, 1.3, 1.1, 0.55. Basis length 2.15 times width with one proximodorsal seta and one UB distoventral seta. Ischium width 1.05 basis, with six dorsal plumose setae and one UB distoventral seta. Merus with one plumose dorsal seta and three UB and two simple setae. Carpus length 1.35 times width, with 15 dorsal and 13 ventral plumose setae and three UB setae distodorsally. Propodus length 1.95 times width; dorsal margin serrated with 14 plumose setae; ventral margin with eight plumose setae, one stout UB seta, and one broom seta distodorsally. Dactylar dorsal claw three times longer than tiny ventral claw.
Pleopod I (male holotype, ZMH K-45652,
Figure 30A) length 2.4 times basal width; distal margin projected, its width 0.3 times basal width; distomedial lobe length 0.05 times pleopod I length, not separated from distolateral weak projections; distolateral margin with 17 small setae.
Pleopod II (male holotype, ZMH K-45652,
Figure 30B) protopod length 1.65 times width, 0.95 times pleopod I length; distolateral margin with few simple setae; distomedial notch length 0.3 times medial margin length. Stylet length 0.55 times protopod length, tip not reaching behind protopod tip; sperm duct opening at midlength. Exopod distal article slightly wider and shorter than basal article.
Pleopod III (male holotype, ZMH K-45652,
Figure 30C) protopod length 0.65 times width, endopod length 1.3 times width, length of three distal plumose setae 0.6 times pleopod III length. Exopod subequal in length to protopod and endopod together and 0.4 times as wide as endopod, with row of fine simple marginal setae; plumose distal seta slightly shorter than endopod distal setae.
Pleopod IV (male holotype, ZMH K-45652,
Figure 30D) endopod length 1.35 times width; exopod 0.9 times endopod length and 0.6 times endopod width. Stout plumose distal seta length 0.6 times exopod length.
Pleopod V (male holotype, ZMH K-45652,
Figure 30E) length 1.2 times width.
Uropod (male holotype, ZMH K-45652,
Figure 26C) length 0.3 times pleotelson length; protopod broadening apically, length 1.0 times width, with five whip and three UB distal setae; endopod as long as protopod, width 0.5 times protopod width, with five simple, five broom, and six UB distal setae; exopod as long as endopod, width 0.5 times endopod width, with four UB and two small simple distal setae.
Female (paratype, ZMH K-45653,
Figure 26D) habitus is similar to male. Body length 2.1 times pereonite 5 width.
Pleopod II (female paratype, ZMH K-45655,
Figure 26E) length 0.7 times width, margins with about 30 small simple setae, ventral keel 0.7 times pleopod II length.
Remarks. The new species differs from other species of the complex by its broad and long rostrum in comparison to the size of antenna I article 1—it is 1.7 times longer than article 1 of antenna I.
Etymology: The name honors Sarah Schnurr’s daughter, Emma Lutz.
Distribution: Known only in the type locality in the Denmark Strait, the Norwegian Sea, and the Iceland–Faroe Ridge, featuring a depth range of 316–686 m.
3.8. Eurycope jakobi Schnurr & Malyutina sp. nov.
Paratypes: female (ZMH K-45658), 2.2 mm length, used for dissection; (ZMH K-45657), used for dissection; and 1 further specimen (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum not tapering distally, length 1.1 times basal width, 1.5 times antenna I article I length, width 1.6 times antenna I basal width. Maxilliped endite with three coupling hooks. Basis lateral projection near palp insertion as long as article 1. Palp article 4 medial lobe length 0.8 times article 5 length. Epipod length 2.4 times width, 0.8 times basis length, width 1.2 times basis width. Male pleopod I length 3.25 times width; distomedial lobe length 0.2 times pleopod I length, width 0.25 times pleopod I width; distolateral lobes slightly projected. Male pleopod II protopod distomedial notch length 0.25 times medial margin length. Uropod protopod length 1.0 times width; endopod length 1.2 times protopod length, width 0.75 times protopod width; exopod length 1.0 times endopod length.
Description of male (holotype, ZMH K-45656,
Figure 31A–C): Length 1.95 times pereonite 5 width. Cephalon length behind antennulae half of pereonite 1 length; interantennular distance 1.3 times antenna I basal width, 0.4 times cephalon width. Rostrum length equal width, 1.5 times antenna I article I length; medial groove deep. Pereonite 5 width 1.5 times pereonite 1 width; pereonite 7 posterior width 1.2 times pereonite 1 width. Natasome length 2.4 times anterior body part length. Pereonites 5 and 6 subequal in length; pereonite 7 longest medially, length 0.7 times pereonites 5 and 6’s combined medial length. Ventral projection of pereonites 6 and 7 0.4 times body length. Pleotelson length 0.75 times width, 0.3 times body length.
Antenna I (male holotype, ZMH K-45656,
Figure 31D) article 1 length 1.2 times width; article 2 length 0.35 times article 1 length, 0.85 times distomedial lobe of article 1 length; articles 3 and 4 lengths 1.0 times and 0.33 times article 2 length, respectively; articles 3 and 4 widths 0.55 times article 2 width. Flagellum broken off.
Antenna II (male holotype, ZMH K-45656,
Figure 31C) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Pereopods broken off (male holotype, ZMH K-45656,
Figure 31B) basis I length 0.2 times body length; bases II, V, VI, VII lengths 0.1, 0.6, 0.7, 0.7 times basis I length, respectively.
Pleopod I (male holotype, ZMH K-45656,
Figure 32A) length 2.3 times basal width; distal width 0.3 times basal width margin, with distomedial lobes projected triangular; length 0.05 times pleopod I length, distolateral lobes almost not visible; distolateral margins with small setulae.
Pleopod II (male holotype, ZMH K-45656,
Figure 32B) protopod length 1.55 times width, 0.95 times pleopod I length; lateral margin with one simple seta; distomedial notch length 0.25 times medial margin length. Stylet length 0.6 times protopod length, tip reaching behind protopod tip; sperm duct opening at 0.3 times length from proximal margin. Exopod distal article half as long and wide as basal article.
Pleopod III (male holotype, ZMH K-45656,
Figure 32C) protopod length 0.7 times width; endopod length 1.35 times width; three distal plumose setae length 0.3 times pleopod III length; exopod as long as protopod and endopod together and 0.3 times as wide as endopod, with row of fine simple lateral setae; simple distal seta slightly shorter than endopod distal setae.
Pleopod IV (male holotype, ZMH K-45656,
Figure 32D) endopod length 1.45 times width, exopod 0.95 times endopod length and 0.5 times endopod width. Stout plumose distal seta as long as pleopod III endopod distal setae.
Pleopod V (male holotype, ZMH K-45656,
Figure 32E) length 1.45 times width.
Female (paratype, ZMH K-45658 and ZMH K-45657,
Figure 33A,D) habitus is similar to male. Body length 1.9 times pereonite 5 width.
Antenna I (female paratype, ZMH K-45658,
Figure 33C) broken off after article 2. Article 1 length 1.15 times width; distomedial lobe tapering distally, with one broom medial and two small medial and three small UB distal setae; one broom seta on distolateral angle. Article 2 length 1.3 times width, with one long broom and two simple small distal setae.
Antenna II (female paratype, ZMH K-45657,
Figure 33A) length 1.7 times body length; articles 1–4 subequal in length; squama on article 3 half of article 4 length. Article 5 length 2.3 times articles 1–4 length, width 1.5 times article 4 width; article 6 length 1.05 times article 5 length, width 0.6 times article 5 width; flagellum as long as previous part of antenna II, of about 30 articles.
Mandible (female paratype, ZMH K-45658,
Figure 34A,B) incisor with four and three cusps and spine row with nine and eight spines on right and left mandibles, respectively; lacinia mobilis of left mandible visibly shorter than incisor, with three distal teeth; molar process distodorsally acute, with four thin setae on base of denticles. Proximoventral margin and lateral margin of palp article 1 denticulated. Palp length subequal to mandible body length; article 2 with three distal setae; articles 2 and 3 lengths 1.9 times and 1.0 times article 1 length, respectively. Article 3 distal seta length 2.5 times other marginal setae and 0.7 times article 3 length.
Maxilla I (female paratype, ZMH K-45658,
Figure 34C) mesial endite width 0.6 times lateral endite width, with fine distal setae and stout long distomedial seta; lateral endite with 12 robust differently serrated setae.
Maxilla II (female paratype, ZMH K-45658,
Figure 34D) middle endite shortest, lateral endite longest; mesial endite with thin distal setae, middle and lateral endites with two long and two shorter distal setae.
Maxilliped (female paratype, ZMH K-45658,
Figure 34E) basis length 3.4 times width; endite width 0.5 times basis width, with three coupling hooks; distal margin with four fan setae. Basis acute lateral projection near palp insertion as long as lateral projection on article 1. Palp length 2.1 times width, 0.7 times basis length. Article 2 length 0.8 times width; width 1.1 times basis width; lateral length equal to medial length; three small distal setae laterally and medially. Article 3 width 0.9 times article 2 width; medial length 0.95 times article 2 medial length; lateral length 0.4 times article 2 lateral length; medial margin denticulate, with few small setae. Article 4 equal to article 3 in lateral length, with two lateral setae; medial lobe length 0.8 times article 5 length, with three distal setae. Article 5 with four lateral and five long distal setae. Epipod length 2.4 times width, 0.8 times basis length; width 1.2 times basis width.
Pleopod II (female paratype, ZMH K-45657,
Figure 33E) length 0.75 times width; lateral margins with two small simple setae, distolateral margins with 10 setae; ventral keel 0.7 times pleopod II length.
Uropod (female paratype, ZMH K-45658,
Figure 33F) length 0.3 times pleotelson length; protopod broadening distally, length 1.0 times width, with one UB and one broom distal setae; endopod length 1.1 times protopod length, width 0.5 times protopod width, with two simple, three broom, and six UB distal setae; exopod as long as endopod, width 0.5 times endopod width, with five UB and two small simple distal setae.
Etymology: The name honors Sarah Schnurr’s son, Jakob Lutz.
Distribution: Known only from the type locality in the Iceland Basin and the Irminger Basin, featuring a depth range of 1385–1588 m.
3.9. Eurycope mathiasi Schnurr & Malyutina sp. nov.
Paratypes: female (ZMH K-45662), used for dissection; female (ZMH K-45663), used for dissection; and 2 further specimens (see
Table 1 for specimen information).
Diagnosis: Cephalon rostrum tapering distally, length 0.75 times basal width, 1.15 times antenna I article I length, width 1.4 times antenna I basal width, distomedial lobe of antenna 1 not reaching tip of rostrum. Maxilliped endite with three coupling hooks. Basis lateral projection near palp insertion length 1.1 times article 1 length. Palp article 4 medial lobe length 1.2 times article 5 length. Epipod length 2.1 times width, 0.9 times basis length; width 1.2 times basis width. Uropod protopod length 1.4 times width; endopod length 1.05 times protopod length, width 0.5 times protopod width; exopod length 0.8 times endopod length.
Description of female (holotype, ZMH K-45660,
Figure 35): Body length 1.75 times pereonite 5 width. Cephalon behind antennulae half as long as pereonite 1; interantennular distance 1.5 times antenna I basal width, 0.5 times cephalon width. Rostrum length 0.8 times basal width, 1.15 times antenna I article I length; medial groove small; distal width 0.55 times basal width, small setae distally. Pereonite 5 width 1.55 times pereonite 1 width; pereonite 7 posterior width 1.2 times pereonite 1 width. Natasome length 2.2 times anterior body part length. Pereonites 5 and 6 subequal in length; pereonite 7 longest medially. Pereonite 7 medial length 0.65 times pereonites 5 and 6’s combined medial length. Ventral projection of pereonite 6 0.35 times body length. Pleotelson length 0.8 times width, 0.35 times body length.
Antenna I (female paratype, ZMH K-45662,
Figure 36A) broken off, article 1 length 1.2 times width, with two broom dorsal setae, one small UB seta, and one small simple seta distomedially; article 2 length 1.4 times width, 0.45 times article 1 length, tip not reaching tip of distomedial lobe of article 1; two broom and three UB distal setae; articles 3 broken off.
Antenna II (female holotype, ZMH K-45660,
Figure 35B) broken off after article 4; articles 1–4 subequal in length; squama on article 3 reaching midlength of article 4.
Maxilliped (female paratype, ZMH K-45663,
Figure 36B) basis length 2.9 times width; endite width 0.6 times basis width, with three coupling hooks; distal margin straight, with three fan setae. Basis acute lateral projection near palp insertion length 1.1 times article 1 lateral length. Palp length 2.1 times width, 0.8 times basis length. Article 2 as long as wide, slightly wider than basis; lateral length 1.15 times medial length; lateral and medial margins with four small setae each. Article 3 almost as wide as article 2; medial margin denticulate, with 10 small setae; medial length 0.85 times article 2 medial length; lateral margin with two small simple setae, length 0.35 times article 2 lateral length. Article 4 equal lateral length 0.8 times article 3 length; medial lobe length 1.2 times article 5 length, with four long distal setae. Article 5 with four lateral and five long distal setae. Epipod length 2.1 times width, 0.9 times basis length; width 1.2 times basis width.
Pereopods broken off.
Pleopod II (female paratype, ZMH K-45662,
Figure 37A) length 0.85 times width; lateral margin with one small simple seta; distolaterally three small simple setae; ventral keel 0.7 times pleopod II length.
Pleopod III (female paratype, ZMH K-45662,
Figure 37B) protopod length 0.5 times width; endopod length 1.25 times width; three distal plumose setae length 0.4 times pleopod III length; exopod reaching slightly behind endopod distal margin, 0.4 times as wide as endopod, with row of fine simple lateral setae; distal simple seta length slightly shorter than endopod distal setae.
Pleopod IV (female paratype, ZMH K-45662,
Figure 37C) endopod length 1.45 times width; exopod 0.9 times endopod length and 0.45 times endopod width. Stout plumose distal seta length 1.3 times length of pleopod III endopod distal setae.
Pleopod V (female paratype, ZMH K-45662,
Figure 37D) length 1.35 times width.
Uropod (female paratype, ZMH K-45662,
Figure 37E) length 0.3 times pleotelson length; protopod broadening apically, length 1.1 times width, with one UB and five whip distal setae; endopod length 1.05 times protopod length, width 0.5 times protopod width, with four simple, four broom, and six UB distal setae; exopod length 0.8 times endopod length, width 0.5 times endopod width, with four distal setae.
Etymology: The name honors Sarah Schnurr’s husband, Mathias Lutz.
Distribution: Known only from the type locality in the Irminger Basin, featuring a depth range of 214–698 m.