Careproctus (Allochir) ambustus, Orr & Pitruk & Manning & Stevenson & Gardner & Spies, 2020

Orr, James W., Pitruk, Dmitry L., Manning, Rachel, Stevenson, Duane E., Gardner, Jennifer R. & Spies, Ingrid, 2020, A New Species of Snailfish (Cottiformes: Liparidae) Closely Related to Careproctus melanurus of the Eastern North Pacific, Copeia 108 (4), pp. 711-726 : 713-721

Careproctus (Allochir) ambustus , new species, Orr

Scorched Snailfish urn:lsid:zoobank.org:act:BF1517AE-707D-4A19-9E70-9506386F3188

Figures 2–4 , Tables 1–3

Careproctus melanurus : Quast and Hall, 1972:28 (in part, Alaska, checklist).—Fedorov, 1973:66 (Bering Sea).— Stein, 1978:16 (in part, Alaska and British Columbia, review).— Allen and Smith, 1988:66 (‘‘blacktail snailfish,’’ in part, Alaska, atlas).— Kido and Shinohara, 1997:127 ( Japan).— Orlov, 1998:146 (Kuril Islands, Kamchatka).— Orlov, 2000:189 (Kuril Islands, Kamchatka, western Bering Sea).— Sheiko and Fedorov, 2000:32 (Kamchatka).— Mecklenburg et al., 2002:616 (in part, Alaska, synopsis, illustration, in key).—Chernova et al., 2004:11 (in part, checklist).— Love et al., 2005:102 (in part, Alaska and British Columbia, checklist).— Orlov, 2005:146, tables 2–5 (Kuril Islands).— Knudsen et al., 2007:659, fig. 3 (phylogeny).— Knudsen and MØller, 2008:179 (comparison with C. kidoi ).— Orlov and Binohlan, 2009:225, table 1 (length– weight relationships, western Bering Sea).— Shinohara et al., 2009:720 (Pacific Japan).— Kai et al., 2011a:353 (compared with C. notosaikaiensis ).— Kai et al., 2011b:146 (compared with ‘‘ Careproctus sp. 2 ’’).— Orlov and Tokranov, 2011:2, fig. 3 (life history, Russia).— Nakabo and Kai, 2013:1211 (in part, Pacific Japan, illustration, in key).— Overdick et al., 2014:132 (eggs).— Parin et al., 2014:322 (and citations within, Russia, checklist).— Orr et al., 2014a:20 (eastern Bering Sea).— Orr et al., 2014b:30, 165 (Gulf of Alaska and Aleutian Islands).—Datsky, 2015:808 (western Bering Sea).—Gardner et al., 2016:648, tables 2–3, figs. 2A, 4, 5, appendix 1 (eggs deposited in crabs, molecular phylogeny).— Kells et al., 2016:212, facing illustration (in part, Alaska, field guide).— Shen et al., 2017:S12, table S2, fig. S5–S6 (molecular phylogenetics, ‘‘KU28298’’ ¼ KU28098).— Pietsch and Orr, 2019:802 (in part, northern populations, illustration).

Careproctus sp. cf. melanurus : Shen et al., 2017:S14, table S2, fig. S6 (molecular phylogenetics).— Orr et al., 2019:17, table 3, figs. 10, 12, appendix tables 1–2 (molecular phylogenetics).

Holotype.— UW 152101 *, 323 mm, ripe male, Aleutian Islands , 51.84028N, 173.8868W, 330 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 90, 1 July 2012, J. W. Orr.

Paratypes.— Total of 63 specimens, 97–420 mm. Eastern Bering Sea : UW 158238 *, 275 mm, 58.52408N, 176.12688W , 677 m depth, F/ V Cape Flattery , cruise 2016-01, haul 81, 6 July 2016; HUMZ 81828 , 1 , 54.558N, 167.658W , 800 m depth, Yakushi Maru , 14 June 1979; HUMZ 81887 , 1 , 56.188N, 169.458W , 530 m depth, Yakushi Maru , 17 June 1979; HUMZ 82669 , 1 , 55.988N, 170.288W , 780 m depth, Yakushi Maru , 7 July 1979; HUMZ 82670 , 1 , 55.988N, 170.288W , 780 m depth, Yakushi Maru , 7 July 1979; HUMZ 82895 , 1 , 56.028N, 169.38W , 610 m depth, Yakushi Maru , 18 June 1979; HUMZ 82896 , 1 , 56.028N, 169.38W , 610 m depth, Yakushi Maru , 18 June 1979; HUMZ 93335 , 1 , 56.688N, 173.278W , 470 m depth, Ryoan Maru 31, 19 August 1981; RBCM 16115, 410 mm, north of Unalaska , 54.958N, 167.358W , 377–457 m depth, M/ V Paragon II, cruise 1978-01, hauls 200–202, 16 August 1978; UW 25177, 385 mm, 558N, 1678W, 1 October 1981, J. Linville. Aleutian Islands : UW 118920 *, 300.6 mm, 53.63458N, 165.05928W , 407 m depth, F/ V Pacific Explorer , cruise 2009-01, haul 15, 28 May 2009, J. W. Orr; UW 150548 *, 380 mm, 59.64298N, 142.71698W , 446 m depth, F/ V Gladiator , cruise 2007-01, haul 260, 23 July 2007, J. W. Orr; UW 151029 *, 328.1 mm, 52.83808N, 172.33838E , 313 m depth, F/ V Sea Storm , cruise 2010-01, haul 208, 6 August 2010, K. P. Maslenikov; UW 156087 *, 4, 97–110 mm, 53.42578N, 165.7978W , 515 m depth, F/ V Alaska Provider, cruise 2013-01, haul 11, 1 June 2013, D. Drumm; HUMZ 102016–102018 , 3 , eastern Aleutians , 53.68N, 164.858W , 535 m depth, Daikichi Maru 37, 27 July 1984; HUMZ 68500 , 1 , west of Attu I., 52.978N , 1718E, 580 m depth, Tanshu Maru , 25 June 1977; HUMZ 88391 , 1 , northeast of Amlia I., 52.338N, 173.238W , 600 m depth, Hatsue Maru , 15 July 1980; HUMZ 88393 , 1 , northeast of Amlia I., 52.338N, 173.238W , 600 m depth, Hatsue Maru , 15 July 1980; HUMZ 88521 , 1 , off Herbert Is., 52.48N, 170.378W , 300 m depth, Hatsue Maru, 27 July 1980; HUMZ 88753 , 1 , east of Agattu Is. , 52.38N, 174.048E , 418 m depth, Hatsue Maru 62, 16 August 1980; HUMZ 88767 , 1 , off Attu Is., 52.628N, 172.738E , 550 m depth, Hatsue Maru , 19 August 1980; HUMZ 88768–88770 , 3 , off Attu Is., 52.588N, 172.838E , 412 m depth, Hatsue Maru , 19 August 1980; HUMZ 88789–88794 , 6 , off Attu Is., 52.828N, 172.28E , 446 m depth, Hatsue Maru , 21 August 1980. Gulf of Alaska: UW 150528 *, 270 mm, 59.56808N, 142.92518W , 570 m depth, F/ V Gladiator , cruise 2007-01, haul 259, 23 July 2007, J. W. Orr; UW 151215 *, 130 mm, 58.99028N, 152.60278W , 148 m depth, F/ V Ocean Explorer , cruise 2011- 01, haul 205, 7 July 2011, J. W. Orr; UW 151242 *, 2, 132– 135 mm, 55.73108N, 154.33038W , 625 m depth, F/ V Ocean Explorer , cruise 2011-01, haul 206, 8 July 2011; UW 153536 *, 260 mm, 58.78038N, 140.97518W , 621 m depth, F/ V Northwest Explorer , cruise 2005-01, haul 261, 22 July 2005, J. W. Orr; UW 154478 *, 122 mm, 59.56418N, 143.02078W , 501 m depth, F/ V Gladiator , cruise 2007-01, haul 258, 23 July 2007, J. W. Orr; UW 156553 *, 2, 280– 350 mm, 55.22148N, 156.72828W , 192 m depth, F/ V Cape Flattery , cruise 2015-01, haul 83, 12 July 2015, M. Zimmermann; UW 156580 *, 390 mm, 58.1284, 137.0457 W , 240 m depth, F/ V Sea Storm , cruise 2015-01, haul 290, 29 July 2015; UW 158236 *, 420 mm, 57.74508N, 149.78518W , 423 m depth, F/ V Ocean Explorer, cruise 2017-01, haul 192, 15 July 2017, R. Manning ; UW 158237 *, 400 mm, 57.03918N, 151.32058W , 582 m depth, F/ V Ocean Explorer, cruise 2017-01, haul 183, 13 July 2017, R. Manning ; HUMZ 34423 , 1 , southeast Alaska, 55.928N, 135.428W , 510 m depth, 6 June 1969; SIO 63-536 , 2 , 265–325 mm, 588N, 1468W; SIO 91-59 , 3 , 270–350 mm, 59.24358N, 146.58428W , 432 m depth, F/ V Green Hope , cruise 1990-01, haul 271, 7 September 1990, W. C. Flerx. British Columbia: RBCM 16111, 280 mm, 51.72618N, 130.66818W ,

melanurus . 877 m depth, 19 October 1996; RBCM 16130, 155 mm, Vancouver I., Clayoquot Canyon, 48.92178N, 126.548W , 925 m depth, sta. P88-44, 24 November 1976; RBCM 16420 (out of RBCM 16097 ), 152 mm, off Vancouver I., offshore to west of Nootka Sound , 2003 Tow 30, 49.53168N, 127.64138W , 958 m depth, 16 April 2003; RBCM 16421 (out of RBCM 16104 ), 180 mm, off the west coast of Vancouver I., 49.56758N, 127.49678W , 1068 m depth, 9 April 2003; RBCM 16422 (out of RBCM 16127 ), 220 mm, Vancouver I., west of Nootka Sound , 49.56678N, 127.42678W , 931 m depth, 10 March 1999; RBCM 16423 (out of RBCM 16132 ), 120 mm, Vancouver I., 48.73338N, 126.49678W , 550 m depth, 25 February 1988. Russia, northern Kuril Islands : MIMB 38374, 250 mm, 49.33338N, 155.86678E , 715 m depth, R / V Prof. Levanidov, haul 164, 17 October 2000; MIMB 38375, 291 mm, 49.48N, 156.01678E , 630 m depth, Tora Maru 58, haul 75, 19 September 1993, D. L. Pitruk ; MIMB 38376, 264 mm, 49.96728N, 156.58558E , 592 m depth, Tora Maru 58, haul 120, 5 October 1993, D. L. Pitruk ; MIMB 38377, 268 mm, 49.96728N, 156.58558E , 592 m depth, Tora Maru 58, haul 120, 5 October 1993, D. L. Pitruk ; MIMB 38378, 250 mm, 50.30128N, 157.00088E , 550 m depth, Tora Maru 58, haul 130, 6 October 1993, D. L. Pitruk ; ZIN 56417, 291 mm, 49.48N, 156.01678E , 630 m depth, Tora Maru 58, haul 75, 19 September 1993, D. L. Pitruk ; ZIN 56418, 250 mm, 50.30128N, 157.00088E , 550 m depth, Tora Maru 58, haul 130, 6 October 1993, D. L. Pitruk .

Additional material examined.— A total of 129 specimens, 90– 420 mm (see Supplemental Text A; see Data Accessibility).

Diagnosis.— Careproctus ambustus is distinguished from all other North Pacific species of Careproctus except C. melanurus by the combination of the shape of its pelvic disc, which is oval, longer than wide (vs. round or wider than long in other species of Careproctus ), shallowly cupped (vs. flat or deeply cupped), and somewhat smaller than the orbit (vs. minute or large); shallowly notched pectoral fin with elongate rays in the lower lobe (vs. deeply notched with elongate or short rays, or shallowly notched with short rays in other species of Careproctus ); and unique COI haplotypes ( Orr et al., 2019). It is further distinguished morphologically from C. melanurus , with which it has been historically confused, by its higher vertebral and median fin-ray counts (vertebrae 61–67 vs. 56– 62, dorsal-fin rays 57–63 vs. 53–59, anal-fin rays 51–57 vs. 46–52 in C. melanurus ), in combination with its longer pelvic disc (14.1–21.2 vs. 12.6–20.7 % HL in C. melanurus ).

Among other species of subgenus Allochir , C. ambustus is also similar to C. cypselurus and C. colletti , from which it can be further distinguished by its oval and curled pelvic disc (vs. triangular in C. cypselurus and typically triangular in C. colletti ), pinkish red to red body coloration (vs. purplish pink in C. cypselurus and purplish pink to dark purple in C. colletti ), orientation of the opercular spine, which is angled ventrad and extends well below the lower orbital rim (vs. nearly horizontal and above the lower orbital rim in C. cypselurus and C. colletti ), and dark inner surface of the pectoral fin contrasting strongly with the lighter outer surface (vs. dusky inner surface and typically dark outer surface in C. cypselurus and C. colletti ). It is further distinguished from C. colletti by its shallowly notched pectoral fin with a moderately long lower lobe (vs. strongly notched pectoral fin with elongate filamentous rays in the lower lobe in C. colletti ), higher counts of vertebrae, median fin rays, and pyloric caeca (vertebrae 61–67 vs. 59–65, dorsal-fin rays 57–63 vs. 51–57, anal-fin rays 51–57 vs. 47–52, and pyloric caeca 25–37 vs. 8– 13 in C. colletti ). Careproctus ambustus is also similar in body shape and color to C. furcellus but can be distinguished by its rounded snout (vs. prominent protruding snout in C. furcellus ); oval pelvic disk (vs. triangular in C. furcellus ); and long, slender rays in the lower pectoral-fin lobe (vs. short, fleshy rays in C. furcellus ), as well as lower vertebral and median fin-ray counts (vertebrae 61–67 vs. 67–71, dorsal-fin rays 57–63 vs. 61–65, and anal-fin rays 51–57 vs. 54–59 in C. furcellus ). Careproctus ambustus is also distinguished from all species within the subgenus, including three undescribed or unidentified species (see Orr et al., 2019), by differences in COI sequence data ( Orr et al., 2019).

Description.— Body heavy and deep anteriorly, deeper with increasing standard length, tapering slightly posteriorly, moderately compressed; depth at pelvic-disc center 54.4– 85.6 (68.4) % HL. Head large, 17.4–29.7 (23.8) % SL, robust, dorsal profile flattened from nape to orbit, rounded to snout. Snout blunt, slightly projecting anterior to lower jaw. Mouth terminal, small, horizontal; upper jaw 41.4–54.3 (43.8) % HL, maxilla extending to mid-orbit, oral cleft extending to anterior rim of orbit; lower jaw 41.4–54.2 (44.7) % HL. Premaxillary tooth plates matching mandibular tooth plates. Premaxillary and mandibular teeth weakly trilobed in 23–45 (35) oblique rows of 11–27 (11) teeth, higher counts in larger specimens, forming moderately wide bands. Diastema absent at symphysis of upper and lower jaws. Orbit 21.7–34.1 (24.1) % HL, dorsal margin below dorsal contour of head, suborbital depth to upper jaw 8.7–16.7 (11.7) % HL, to lower jaw 23.9– 33.0 (27.1) % HL; pupil round. Interorbital space broad, fleshy distance 32.8–59.7 (48.2) % HL, bony distance 14.7– 27.8 (22.8) % HL, flat to weakly convex. Snout about as long as orbit, 81.7–137.2 (113.0) % OL, 24.3–36.5 (27.2) % HL. Nostril single, at level slightly above midorbit, with well-developed short tube 3.5–14.4 (9.1) % OL.

Pores of cephalic-lateralis system small to moderate size, pore pattern 2-6-7-2, postorbital pore small, possibly absent in some specimens, preoperculomandibular pore 7 smaller than more anterior pores, chin pores paired. Interorbital pore absent.

Gill opening moderate in size, 30.2–45.2 (40.1) % HL, upper margin at or above midorbit, extending ventrally to just above upper pectoral-fin ray. Opercular flap rounded, opercular tip extending well below orbit to cleft or below. Gill rakers 9–12 (11; Tables 1–2), short, blunt.

Dorsal-fin rays 57–63 (60; Tables 1–2), anterior dorsal lobe absent, anterior rays not buried in tissue, tips of more posterior rays not exserted. Anteriormost dorsal-fin pterygiophore inserted between neural spines 3 and 4, rayless or bearing a single small or rudimentary ray (rayless). Predorsal length 22.4–31.3 (29.2) % SL. Anal-fin rays 51–57 (53; Tables 1–2), one or two anal-fin pterygiophores anterior to first haemal spine (one), each bearing a single ray, tips of all rays slightly exserted. Anal-fin origin below vertebrae 11–12 (12), preanal length 33.6–46.5 (38.4) % SL.

Pectoral fin with shallow, nearly indiscernible notch, with 28–35 (29) rays ( Tables 1–2). Upper lobe 68.8–108.1 (90.6) % HL, with 19–26 (19) rays extending well beyond anus near or beyond anal-fin origin to the base of ray 4, slightly longer than lower lobe, dorsalmost rays lengthening to rays 8–10, more ventral rays gradually shortening to shortest ray of notch. Lower lobe elongate, 60.3–104.9 (88.7) % HL, with 7– 11 rays (10), extending well beyond anus to 70% or more of the distance between the anus and anal-fin origin; uppermost rays gradually lengthening to elongate rays 4–5, ventral rays gradually shortening to ventralmost ray near pectoral symphysis. Tips of rays in upper lobe 0–5 % free of membrane, rays of lower lobe more strongly exserted up to 70% free. Notch shallow, rays in notch slightly more widely spaced than rays of lobes, more widely spaced ventrally. Uppermost pectoral-fin ray level with cleft. Insertion of lowermost pectoral-fin ray below anterior part of orbit.

Proximal pectoral radials four (3 þ 1), rounded, thin: radial 1 notched dorsally at scapular fenestra; radials 2 and 3 round, unnotched; radial 4 widely spaced from more dorsal radials, small, round ( Fig. 4 ). Single interradial fenestra extending between scapula and proximal radial 1 an irregular oval. Scapula with robust distally broadened helve; coracoid broadly triangular with narrower helve and upper rib, angled slightly anteriorly. Distal radials present at base of rays 2–25, ventralmost at level of proximal radial 4, dorsalmost ray and more ventral rays articulating directly with the pectoral cartilage or with a separate fibrocartilage pad.

Pelvic disc small, length 14.1–21.2 (18.0) % HL, shorter than orbit, 52.4–87.3 (63.5) % OL, shallowly cupped, oval, curled, nearly round and slightly more elongate when flattened, width when curled 5.1–13.9 (9.1) % HL, when flattened 10.4–17.1 (13.1) % HL, 39.5–100.0 (72.8) % pelvic length, anterior lobe weakly developed, lateral and posterior margin fleshy and curled medially, more anteroposteriorly shortened in larger mature specimens appearing somewhat triangular, distance from snout to pelvic disc 8.7–12.2 (10.7) % SL. Anus at level slightly behind posterior rim of orbit, close behind pelvic disc; distance from pelvic disc to anus 8.8–31.5 (13.3) % HL.

Principal caudal-fin rays 10–12, dorsal procurrent rays 0–2, ventral procurrent rays 0–2 (1–2 þ 5–6/ 5–6 þ 0–2) (1 þ 6/ 6 þ 0). Caudal fin truncate to rounded, 41.1–66.7 (60.4) % HL. Membrane of posterior dorsal-fin rays attached to caudal fin at slightly shorter distance than anal-fin rays: dorsal-fin rays attached to caudal fin 50.8–87.2 (73.3) % CL; anal-fin rays, 53.7–90.5 (79.3) % CL. Depth at base of caudal fin 5.1–9.4 (7.1) % HL, 7.9–17.3 (17.3) % CL.

Skin thin, flaccid, prickles absent. Pyloric caeca 25–37 ( Kido and Shinohara, 1997), length about 54% HL, centerleft side of visceral cavity.

Vertebrae 61–67 (64), precaudal 9–11 (10), caudal 51–57 (54; Tables 1–2). Pleural ribs 1, 2, or absent (1), all short and slender, anteriormost smallest, present on vertebrae 9–11 (9).

Coloration.— In life ( Fig. 2A ), body pink to red, darker posteriorly; the posterior third of dorsal and anal fins darker along margins to entirely black posteriorly; caudal fin black; pectoral fins red to pink laterally, distally with red to dark red margins and dark membranes, dark red or black medially. Peritoneum overall dark, darkly speckled with little space between, or uncommonly pale with more widely scattered speckles; orobranchial cavity black; stomach pale, intestines pale, pyloric caeca pale; urogenital papilla dark or mottled, with light tip, ovipositor white. After preservation, body pale with fins darker posteriorly.

Life history.— Females with a large ovipositor and yolked eggs ranged from 305 to 420 mm (the largest female, UW 154579), and males from 230 to 420 mm (the largest male, RBCM 16115) appeared ripe with large testes. At least two sizes of eggs were present in ripe females: yolked eggs were 3.2–3.8 mm in diameter and white eggs had diameters of 0.5– 1.5 mm. All eggs collected in the wild and verified as those of C. ambustus have been identified from clusters deposited within the lithodid crab Lithodes aequispinus (Gardner et al., 2016, as C. melanurus ). Mean egg sizes in clusters (fixed and preserved in 95% ethanol) collected from crabs in the Aleutian Islands and southeastern Bering Sea ranged from 3.82 to 4.87 mm, with an overall average mean of 4.36 mm (Gardner et al., 2016). Specimens of C. ambustus taken in the western Pacific Ocean off Kamchatka and the Kuril Islands have been aged to 10–13 years ( Tokranov and Orlov, 2001; Orlov and Tokranov, 2011).

Distribution.— Careproctus ambustus is known in the North Pacific Ocean from British Columbia, Alaska, Russia, and Japan ( Fig. 3 ) at depths of 58 to 1,172 m, based on material examined and confirmed field identifications ( Tokranov, 2000; Orr et al., 2014a, 2014b; G. R. Hoff, pers. comm., 2016). In the eastern North Pacific, it ranges from British Columbia off central Vancouver Island, throughout the Gulf of Alaska and Aleutian Islands, and into the eastern Bering Sea to at least 60.38N (Hoff, 2016) and off Cape Navarin in the western Bering Sea ( Parin et al., 2014). In the western North Pacific, it ranges from Kamchatka and the Kuril Islands, Russia ( Orlov, 1998, 1999, 2001; Sheiko and Fedorov, 2000; Orlov and Tokranov, 2011), to the northwestern coast of Honshu, Japan ( Kido and Shinohara, 1997).

Etymology.— The specific epithet of Careproctus ambustus is taken from the Latin ambusti, meaning ‘‘scorched,’’ referring to the black tail that contrasts with the pink to red anterior part of the body.

Figures

FIG. 2. (A) Careproctus ambustus, new species, UW 152101, 323 mm, holotype, Aleutian Islands, 51.84028N, 173.8868W, 330 m depth, photographed before fixation and preservation; (B) Careproctus melanurus, UW 47264, 205 mm, Oregon, 44.39938N, 124.83558W, 447 m depth, photographed before fixation and preservation.

FIG. 3. Distribution of Careproctus ambustus, new species (black), and C. melanurus (white) in the Bering Sea and North Pacific Ocean based on material examined. Each symbol may represent more than one capture. Bottom contour illustrated is 200 m.

FIG. 4. (A) Right medial view of pectoral girdle of Careproctus ambustus, new species, UW 119240, 150 mm; (B) Right medial view of pectoral girdle of Careproctus melanurus, UW 47479, 125 mm. Shaded areas represent cartilage.