AnimaliaAmphipodaAmphilochidaeTandbergAnne Helene S.VaderWimOn a new species of Amphilochus from deep and cold Atlantic waters, with a note on the genus Amphilochopsis (Amphipoda, Gammaridea, Amphilochidae)Zookeys2312018201873110313410.3897/zookeys.731.19899 Amphilochus anoculus http://zoobank.org/AD3ED2F5-F13B-4885-BD81-492F173B4EA1 sp. n.Material examined.

from Icelandic (BioIce and IceAGE), Norwegian coastal and arctic (Svalbard) and Faroese waters. (For an extensive list of examined material see Table 1.).

List of stations for examined species of Amphilochus anoculus sp. n., A. manudens, and A. hamatus. Asterisk * after museum-number indicates holo- and paratypes.

SpeciesStation nameSampling programmeCollection numberLatitude (dec)Longitude (dec)Depth (m)Temp (C) BOLD-accension numberNote
Amphilochus anoculus sp. n.BioIce 2087BioIce 67,257, -17,446 735,0-0,40
BioIce 2088BioIce 67,239, -17,857 617,0-0,40
BioIce 2094BioIce 67,034, -17,570 303,01,70
BioIce 2100BioIce 68,001, -19,421 1141,0-0,60
BioIce 2107BioIce 67,836, -19,555 905,0-0,60
BioIce 2136BioIce 66,726, -18,953 417,00,60
BioIce 2149BioIce 66,749, -20,086 293,03,00
BioIce 2318BioIce IINH37886 (wet), IINH37916 (slide) 64,070, -9,030 996,0
BioIce 2325BioIce 63,750, -10,183 555,0
BioIce 2367BioIceIINH37888, IINH37914*, IINH37915* 64,380, -9,430 719,0Paratype (slides)
3-1Akvaplan NIVA Faroe project 60,348, -5,167 1088,0
8-1Akvaplan NIVA Faroe project 60,591, -5,309 825,0
9-1Akvaplan NIVA Faroe project 60,538, -5,206 921,0
13-2Akvaplan NIVA Faroe project 60,483, -4,932 1022,0
15-1Akvaplan NIVA Faroe project 60,553, -4,937 1055,0
15-3Akvaplan NIVA Faroe project 60,553, -4,937 1055,0
81 03211Tromsø Museum Collection tours TSZCr 15516 63,167, 4,817 860,0
14968Tromsø Museum Collection tours TSZCr 14968 70,850, 15,383 2100,0
JM 369-05UNIS AB321-2005 TSZCr 14338* 80,531, 10,578 819,0Paratypes (wet)
R405 RP59MareanoZMBN_111537 72,140, 15,346 902,4-0,41AMPNB487-17
R479 RP156Mareano 68,653, 10,301 2744,2-0,82
R573 RP28Mareano 70,872, 16,933 916,5-0,64
R642 RP104MareanoZMBN_104532 68,241, 9,243 2346,6-0,84AMPNB354-15
R653 RP108Mareano 67,608, 8,392 1750,7-0,84
R671 RP111MareanoZMBN_104531 67,891, 9,875 777,2-0,52AMPNB353-15
R1180 RP86Mareano 71,609, 32,992 304,92,84
Amphilochus anoculus sp. n.R1200 RP90Mareano 70,854, 32,507 248,93,74
R1225 RP112MareanoZMBN121953 * 70,475, 31,734 401,45,45Paratype (slide)
R1225 RP112MareanoZMBN121959, ZMBN121960 70,475, 31,734 401,45,45slides
IceAGE 1010IceAGE ZMH K-47220 62,552, -20,395 1384,8
IceAGE 1010IceAGE ZMH K-47221 62,552, -20,395 1384,8
IceAGE 1054IceAGE ZMH K-47222 61,603, -31,377 2537,3
IceAGE 880IceAGEZMBN121954 63,389, -8,157 686,0
IceAGE 880IceAGE ZMH K-47223 63,389, -8,157 686,0AMPIV181-17
IceAGE 1010IceAGEZMBN121955 62,552, -20,395 1384,8
IceAGE 1010IceAGE ZMH K-47224 62,552, -20,395 1384,8AMPIV188-17
IceAGE 1057IceAGE ZMH K-47225* 61,642, -31,356 2504,7Holotype (slide)
IceAGE 1168IceAGE ZMH K-47226 67,606, -7,001 2372,6
IceAGE 1123IceAGE ZMH K-47227 67,214, -26,208 716,5
IceAGE 1172IceAGE ZMH K-47228 67,578, -6,935 2422,4
IceAGE 1181IceAGEZMBN121956 67,658, -12,227 1827,0
IceAGE 1119IceAGEZMBN121957 67,214, -26,242 696,9
IceAGE 871IceAGEZMBN121958 62,737, -0,946 1577,4
IceAGE 1168IceAGE ZMH K-47229 67,606, -7,001 2372,6
IceAGE 1123IceAGE ZMH K-47230 67,214, -26,208 716,5
IceAGE 1172IceAGE ZMH K-47231 67,578, -6,935 2422,4
IceAGE 1172IceAGE ZMH K-47232 67,578, -6,935 2422,4DNA-voucher: ZMH K-47232
IceAGE 1054IceAGE ZMH K-47233 61,603, -31,377 2537,3DNA-voucher: ZMH K-47233
IceAGE 1159IceAGE ZMH K-47234 69,111, -9,917 2202,8
IceAGE 868IceAGE ZMH K-47235 62,152, 0,259 587,4
IceAGE 1123IceAGE ZMH K-47236 67,214, -26,208 716,5
IceAGE 1010IceAGE ZMH K-47237 62,552, -20,395 1384,8DNA-voucher: ZMH K-47237
IceAGE 1006IceAGEZMBN121952* 62,551, -20,375 1386,8Paratype (slide)
Amphilochus manudens Spence Bate, 1862BioIce 2096BioIce 67,018, -17,578 300,01,70
BioIce 2207BioIceIINH37889 67,011, -22,596 81,08,30
BioIce 2213BioIce 64,155, -23,971 260,07,00
BioIce 2215BioIceIINH37887 64,157, -24,261 213,06,90
BioIce 2221BioIce 63,917, -25,273 240,06,50
BioIce 2236BioIce 63,450, -24,680 293,06,90
BioIce 2237BioIceIINH37885 63,270, -24,408 293,06,90
BioIce 2273BioIce 63,140, -24,983 313,07,00
BioIce 2288BioIce 62,387, -22,677 1390,03,40
BioIce 2308BioIce 63,250, -22,790 263,07,10
BioIce 2314BioIce 63,703, -23,058 139,07,60
BioIce 2352BioIce 63,783, -11,817 350,0
BioIce 2358BioIce 63,167, -11,533 318,0
BioIce 2720BioIce 64,430, -26,403 304,05,60
R405 RP59Mareano 72,137, 15,341 899,6-0,41
R423 RP69Mareano 71,872, 17,142 355,35,53
R474 RP154Mareano 71,073, 18,543 251,07,52
R503 RP51Mareano 71,772, 25,975 321,14,42
R534 RP60Mareano 70,675, 18,622 364,66,34
R608 RP87Mareano 70,958, 21,120 149,06,57
R613 RP90Mareano 70,769, 20,818 246,86,42
R618 RP91Mareano 70,701, 21,025 258,86,38
R621 RP93Mareano 70,673, 20,852 195,67,28
R631 RP99Mareano 70,805, 19,702 178,66,87
R636 RP102Mareano 70,622, 20,104 289,76,98
R657 RP109Mareano 67,343, 8,638 849,6-0,84
R721 RP126Mareano 67,841, 11,809 183,26,87
R733 RP128MareanoZMBN_94864 67,720, 10,272 219,27,34AMPNB115-14
R754 RP132Mareano 67,803, 9,685 823,5-0,56
R786 RP10Mareano 67,953, 9,589 1315,4-0,84
Amphilochus manudens Spence Bate, 1862R782 RP11Mareano 68,059, 9,468 1712,0-0,81
R821 RP13MareanoZMBN_104481 67,021, 8,223 556,0AMPNB303-15
R870 RP19Mareano 67,387, 11,622 128,36,29
R849 RP21Mareano 67,401, 10,822 179,67,51
R1137 RP77Mareano 72,574, 32,386 272,32,09
R1146 RP80Mareano 72,103, 34,287 288,92,18
R1150 RP82Mareano 72,093, 33,701 249,52,83
R1174 RP85Mareano 71,618, 32,225 296,53,39
R1180 RP86Mareano 71,609, 32,992 304,92,84
R1186 RP87Mareano 71,421, 32,859 281,54,47
R1196 RP89Mareano 71,187, 32,243 226,04,27
R1200 RP90Mareano 70,854, 32,507 248,93,74
R1205 RP92Mareano 70,574, 32,273 297,34,22
R1213 RP93Mareano 70,771, 30,785 376,14,62
R1230 RP95Mareano 70,117, 31,350 303,9
IceAGE 868IceAGE ZMH K-47238 62,152, 0,259 587,4
IceAGE 1082IceAGE ZMH K-47239 63,702, -26,394 724,4
IceAGE 1017IceAGE ZMH K-47240 62,931, -20,774 891,7
IceAGE 1032IceAGE ZMH K-47241 63,309, -23,158 289,4
IceAGE 878IceAGE ZMH K-47242 61,897, -10,230 781,4
IceAGE 868IceAGE ZMH K-47243 62,152, 0,259 587,4
IceAGE 1086IceAGE ZMH K-47244 63,709, -26,384 698,1
IceAGE 1219IceAGE ZMH K-47245 66,289, -12,347 579,1
IceAGE 1086IceAGE ZMH K-47246 63,709, -26,384 698,1
IceAGE 876IceAGE ZMH K-47247 60,406, -6,615 554,3
IceAGE 876IceAGE ZMH K-47248 60,406, -6,615 554,3AMPIV183-17
IceAGE 878IceAGE ZMH K-47249 61,897, -10,230 781,4
IceAGE 878IceAGE ZMH K-47250 61,897, -10,230 781,4
IceAGE 878IceAGE ZMH K-47251 61,897, -10,230 781,4
IceAGE 1168IceAGE ZMH K-47252 67,606, -7,001 2372,6
Amphilochus manudens Spence Bate, 1862IceAGE 1104IceAGE ZMH K-47253 66,643, -24,533 118,8
IceAGE 1194IceAGE ZMH K-47254 67,078, -13,055 1573,5
IceAGE 1172IceAGE ZMH K-47255 67,578, -6,935 2422,4
IceAGE 867IceAGE ZMH K-47256 61,997, 0,507 302,5
IceAGE 866IceAGE ZMH K-47257 61,427, 1,351 169,1
IceAGE 870IceAGE ZMH K-47258 62,329, -0,102 1058,4
IceAGE 867IceAGE ZMH K-47259 61,997, 0,507 302,5
IceAGE 1123IceAGE ZMH K-47260 67,214, -26,208 716,5
IceAGE 1082IceAGE ZMH K-47261 63,702, -26,394 724,4DNA-voucher: ZMH K-47261
IceAGE 866IceAGE ZMH K-47262 61,427, 1,351 169,1
IceAGE 867IceAGE ZMH K-47263 61,997, 0,507 302,5
IceAGE 868IceAGE ZMH K-47264 62,152, 0,259 587,4
IceAGE 1086IceAGE ZMH K-47265 63,709, -26,384 698,1DNA-voucher: ZMH K-47265
IceAGE 867IceAGE ZMH K-47266 61,997, 0,507 302,5
IceAGE 867IceAGE ZMH K-47267 61,997, 0,507 302,5DNA-voucher: ZMH K-47267
Amphilochus hamatus (Stephensen, 1925)BioIce 2077BioIceIINH37894 67,405, -17,104 1048,0-0,50
BioIce 2087BioIce 67,257, -17,446 735,0-0,40
BioIce 2088BioIceIINH37892 67,239, -17,857 617,0-0,40
BioIce 2090BioIceIINH37893 67,222, -17,816 539,0-0,40
BioIce 2096BioIceIINH37891 67,018, -17,578 300,01,70
BioIce 2100BioIce 68,001, -19,421 1141,0-0,60
BioIce 2107BioIceIINH37890 67,836, -19,555 905,0-0,60
BioIce 2136BioIceIINH37896 66,726, -18,953 417,00,60
BioIce 2149BioIce 66,749, -20,086 293,03,00
BioIce 2213BioIceIINH37897 64,155, -23,971 260,07,00
BioIce 2236BioIceIINH37898 63,450, -24,680 293,06,90
BioIce 2237BioIce 63,270, -24,408 293,0
Amphilochus hamatus (Stephensen, 1925)BioIce 2317BioIceIINH37889 64,117, -9,050 996,0
BioIce 2318BioIceIINH37900 64,070, -9,030 996,0
BioIce 2319BioIceIINH37901 64,017, -9,617 776,0
BioIce 2340BioIceIINH37902 62,133, -13,333 1302,0
BioIce 2367BioIceIINH37903 64,380, -9,430 719,0
BioIce 2410BioIceIINH37904 62,860, -21,735 1074,04,00
BioIce 2707BioIceIINH37905 63,922, -28,270 1407,03,70
BioIce 2719BioIceIINH37906 64,428, -26,403 300,05,60
R671 RP111MareanoZMBN_104542 67,891, 9,875 777,2-0,52AMPNB364-15
R877 RP3MareanoZMBN_104479 68,475, 9,785 2561,4-0,80AMPNB301-15
R776 RP4Mareano 68,186, 10,354 799,9-0,74
IceAGE 869IceAGE ZMH K-47268 62,270, 0,020 846,4
IceAGE 1006IceAGE ZMH K-47269 62,551, -20,375 1386,8
IceAGE 1006IceAGE ZMH K-47270 62,551, -20,375 1386,8
IceAGE 1019IceAGE ZMH K-47271 62,939, -20,744 913,6
IceAGE 1132IceAGE ZMH K-47272 67,641, -26,755 318,1
IceAGE 1172IceAGE ZMH K-47273 67,578, -6,935 2422,4
IceAGE 1123IceAGE ZMH K-47274 67,214, -26,208 716,5
IceAGE 1119IceAGE ZMH K-47275 67,214, -26,242 696,9
IceAGE 1119IceAGE ZMH K-47276 67,214, -26,242 696,9DNA-voucher: ZMH K-47276
IceAGE 1010IceAGE ZMH K-47277 62,552, -20,395 1384,8
IceAGE 1010IceAGE ZMH K-47278 62,552, -20,395 1384,8DNA-voucher: ZMH K-47278
IceAGE 1172IceAGE ZMH K-47279 67,578, -6,935 2422,4DNA-voucher: ZMH K-47279
IceAGE 869IceAGE ZMH K-47280 62,270, 0,020 846,4
IceAGE 1010IceAGE ZMH K-47281 62,552, -20,395 1384,8

Holotype: IceAGE ZMH K-47225, female 3 mm (slide).

Paratypes: Slides: BioIce 2367 male, 3 mm IINH37914; BioIce 2367 female, 3 mm IINH37915; MareanoR1225-RP112 female 4 mm ZMBN121953; IceAGE 1006 male, 3 mm ZMBN121952. Wet-sample: TSZCr 14338 (8 specimens).

Type locality.

ZMH K-47225: IceAGE station 1057 (61.6417, -31.3562) (2504m).

Paratype localities.

IINH37914, IINH37915: BioIce station 2367 (64.3800, -9.4300) (719m); TSZCr 14338: UNIS course-station JM 369-05 (80.5313, 10.5777) (819 m); ZMBN121953: Mareano station R1225-RP112 (70.4748, 31.7340) (401 m); ZMBN121952: IceAGE station 1006 (62.5508, -20.3750) (1386 m).

Distribution.

This species is known from BioIce/IceAGE stations in deep and cold waters north and east of Iceland, from deep stations in the Faroe-Shetland Channel, several deep stations north in the Norwegian Sea and from one deep station in the polar basin. It appears to be confined to cold and deep waters (see Fig. 1).

Map showing the Icelandic distribution of Amphilochus anoculus sp. n., Amphilochus manudens and Amphilohus hamatus (based on BioIce and IceAGE material).

Illustrations are all from paratypes: Figs 24 of ZMBN121952, except for Fig. 3 pereopod 1 dactylus (1b) which is from ZMH K-47225 and Fig. 4 uropod 3 and telson that are both from BioIce station 2367.

Description.

Description is based on a composite of studied material. No observed sexual dimorphism.

Head. Rostrum subequal to peduncle article 1 of antenna 1, curved. Eyes absent. Cephalic lobes produced, broadly rounded, tips of mouthparts just visible under the edge of cephalon. Antenna 1 subequal to antenna 2; peduncle strong, longer than six-articulate flagellum; accessory flagellum absent. Setae on both peduncle and flagellum few and short. Antenna 2 peduncle longer than eight-articulate flagellum. Few and short setae distally on peduncle articles, all articles of the peduncle are longer than broad.

Labrum symmetrically bilobed. Mandible molar small but triturative, rounded cone-shaped, with setation on entire chewing area, which is ridged; incisor serrate; eleven accessory spines; palp slender, 3-articulate; article 1 is shorter than article 2, which is shorter than article 3; article 3 with setae; lacinia mobilis laterally expanded. Labium symmetrical, without inner lobes. Maxilla 1 palp biarticulate, with two apical setae; inner plate reduced, with one seta; outer plate with eight robust and six thinner setae. Maxilla 2 inner plate shorter than outer plate, nine setae on distal margin; outer plate long and thin with four distal setae. Maxilliped inner plate reaching end of merus, well separated, thin, two robust distal setae; outer plate reaches middle of carpus of palp, one robust seta and ridge of serrations; palp slim, heavily setulated on propodus.

Mesosome dorsally smooth; segment 3 is shorter than segment 4. Coxa 1 reduced and covered by coxa 2, which is longer than broad. Coxa 2 distal margin serrate and with setae. Coxa 3 and 4 distal margin not serrate, without setae. Coxa 5–7 concave.

Pereopod 1 basis longer than propodus, upper half distally widened, few and short setae; carpal lobe well developed, reaching 65% of posterior margin of propodus; propodus triangular; palm oblique, serrate with setae, no seta defining palmar corner, anterodistal tooth of medium size (half as long as the base of dactylus is broad); dactylus smooth with few, thin setae on inner margin. Pereopod 2 basis little longer than propodus, upper half not as widened distally as pereopod 1; carpal lobe covers all of posterior margin of propodus; propodus elongate, palm oblique, serrate with minute setae, no setae defining the palmar corner, anterodistal tooth well developed (same size as the breadth of the base of dactylus); dactylus inner margin weakly serrate on proximal half. Pereopod 3 missing in holotype. Pereopod 4 basis with four anterior setae, dactylus half-length of propodus. Pereopod 5 with posterior lobe on basis and merus. Pereopod 6 with posterior lobe on basis; posterior lobe on merus boat-shaped; carpus shorter than propodus; dactylus more than half length of propodus. Pereopod 7, posterior lobe on basis and merus, meral lobe covers 50% of carpus; dactylus more than half-length propodus.

Metasome smooth. Epimeral plates 1 and 3 rounded; plate 2 right-angled. Urosome smooth; segment 1 long; segments 2 and 3 shorter. Uropod 1 peduncle longer than rami; outer ramus marginally longer than inner; three to four setae on outer margins. Uropod 2 peduncle longer than rami; outer ramus half-length of inner; setae on both rami. Uropod 3 peduncle with clear flange, smooth; outer ramus weakly shorter than inner ramus; uropod 3 longer than telson. Gills on segments 2 to 7; oostegites on segments 2 to 6. Telson elongate and boat-shaped; distal end entire, acute and with one seta.

Amphilochus anoculus sp. n. Head and mouthparts. ZMBN121952. Scale bars: 0.1 mm.

Amphilochus anoculus sp. n. Pereopods 1, 2, 3 and 4. ZMBN121952. Pereopod 1 dactylus from ZMH K-47225. Scale bars: 0.1 mm.

Amphilochus anoculus sp. n. Pereopods 5, 6 and 7, Epimeral plates, Uropods 1, 2 from ZMBN121952. Uropod 3 and telson from BioIce station 2367. Scale bars: 0.1 mm.

Living colour. Semi-transparent, virtually colourless.

Distribution.

Iceland, Faroe Channel, Norwegian Sea, Polar basin. Has only been found in cold and deep water.

Remarks.

This species is easily recognized because it lacks eyes and has an anterodistal tooth on the propodi of pereopods 1 and 2. Amphilochus manudens and A. hamatus are the only other Amphilochidae having this tooth, but unlike Amphilochus anoculus sp. n., they both have eyes. The telson has a robust seta distally, a character not seen in any other Amphilochidae. The flange on the distal end of uropod 3 peduncle is also a good character-state to use when separating it from A. hamatus. A synoptic list of characters separating the three species is shown in Table 2.

Comparison of character states between Amphilochus anoculus sp. n., A. manudens, and A. hamatus.

Character Amphilochus anoculus sp. n. Amphilochus manudens Amphilochus hamatus
Cephalic lobes roundedacuterounded
Labrum symmetrically bilobedasymmetrically bilobedasymmetrically bilobed
Mandible molar roundedmolar conicalmolar conical
1st Maxilla palp 2-articulatepalp 2-articulatepalp 1-articulate
2nd Maxilla outer plate with 4 setaeouter plate with 3 setaeouter plate with 3 setae
Labium tooth on inner edge of outer plateno tooth on inner edge of outer platetooth on inner edge of outer plate
Eyes absentround, strongly colouredill defined, bean-shaped or oval
Gnathopod 2 elongatesubtriangularelongate
Oostegites on P6 presentabsentpresent
Epimeral plate 1 roundedangularangular
Epimeral plate 3 roundedwith clear toothrounded
Uropod 3 with flange on peduncleno flange on peduncleno flange on peduncle
Telson tip with robust setatip smoothtip tridentate – all lobes rounded.
Temperature (°C) -0.6 to + 1.7+1.7 to + 7-0.85 to +7
Depth (m) 303m to 1055m81m to 350m (single specimens at 772m and 1390m)260m to 1407m
Biology.

This species appears to be restricted to cold water (it is only found at a temperature range of -0.6 °C to +1.7 °C. Three stations from the Mareano-project have higher temperatures than this (stations R1180 RP86, R1200 RP90 and R1225 RP112). These are also the three of the shallowest stations where this species has been found, and constitute a statistical outlier in the dataset. They are all in the eastern Barents Sea, an area where winter-temperatures are much colder, and thus still might fall within the proposed ecological niche of the species. It has been found north and east of Iceland, south of the Faroe Islands, north in the Norwegian Sea and in the Polar basin, at depths ranging from 303 to 2100 meters. In contrast, the closely related Amphilochus manudens has, during BioIce, IceAGE, and several other collection efforts in the area been found mainly at depths from 81 to 360 meters, with single specimens found at 772 and 1390 meters (see Fig. 1 for specimens from BioIce and IceAGE). No Amphilochus manudens were found in the Faroe-samples from AkvaplanNiva.

Derivatio nominis.

The name anoculus (an = no, oculus = eye) refers to the absence of eyes. It is a noun in apposition.