Careproctus candidus Gilbert and Burke 1912
Creators: name: Gardner, Jennifer R.
name: Orr, James W.
name: Tornabene, Luke
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Scorpaeniformes
Liparidae
Careproctus
Careproctus candidus

description: Careproctus candidus Gilbert and Burke 1912
Bigeye Snailfish
Figures 1, 2, 3A, 3B, 4A, 4B, 5; Tables 1, 2; Supplemental Table A
Careproctus candidus Gilbert and Burke 1912 b: 77, fig. 22 (original description).
Type locality: Aleutian Islands, off Attu Island, 135 fms depth; Jordan et al., 1930: 403 (checklist, Aleutian Islands); Soldatov and Lindberg, 1930: 378 (description, in key, possible in Russian waters); Böhlke, 1953: 135 (type catalog); Kido, 1988: 128 (reallocated from Temnocora); Robins et al., 1991: 44 (common name); Mecklenburg et al., 2002: 605 (Alaska, illustration, description, key); Nelson et al., 2004: 124 (common names); Love et al., 2005: 101 (checklist); Page et al., 2013: 127 (common names); Orr et al., 2019: 13 (molecular phylogenetics); Orr, 2021: 465 (compared with C. maslenikovae and C. spiraki).
Temnocora candida: Burke, 1930: 146 (new combination, description, key); Taranetz, 1937: 137 (checklist, Bering Sea); Andriashev, 1939: 47 (not seen, cited in Parin et al., 2002, 2014); Wilimovsky, 1954: 287 (checklist, Bering Sea); Wilimovsky, 1958: 79 (Alaska, Bering Sea, in key); Quast and Hall, 1972: 32 (checklist, Bering Sea and Cook Inlet); Fedorov, 1973a: 21 (not seen, cited in Parin et al., 2002, 2014); Fedorov, 1973b: 67 (Bering Sea); Matarese et al., 1989: 475, table 1 (meristics); Borets, 2000: 98 (not seen, cited in Parin et al., 2002, 2014); Sheiko and Fedorov, 2000: 33 (Russia); Chernova et al., 2004: 51 (checklist); Orr and Maslenikov, 2007: 708, figs. 1C, 2C (compared with C. comus and C. faunus); Datsky, 2015: 808 (western Bering Sea); Orr, 2021 (compared with C. maslenikovae and C. spiraki); Fricke et al., 2021: online (valid).
Temnocara candida: Eschmeyer, 1998: 2147, 2475 (lapsus calami); Parin et al., 2002: S128 (northern Kuril Islands, southeastern Kamchatka, possibly off Commander Islands).
Holotype.— USNM 74384, 60.7 mm, Aleutian Islands, off Attu Island, 52.93 8 N, 173.43 8 E, 247 m (135 fms) depth, Albatross Station 4784, 11 June 1906.
Paratypes.— 3 specimens, 56.3–63.6 mm. CAS-SU 22367, 61.4 mm, collected with holotype; USNM 74527, 2, 56.3–63.6 mm, collected with holotype.
Non-type material examined.— 64 specimens, 27–94.7 mm. CAS-ICH 47731, 74.5 mm, 52.3964 8 N, 174.1347 8 E, 168–188 m depth, R / V Hatsue Maru No. 62, T. Iwamoto, 16 August 1980; UW 48241, 2, 60.5–70.5 mm, 52.3975 8 N, 171.831 8 W, 271 m depth, F/ V Dominator, cruise 2000-01, haul 53, benthic bag, J. W. Orr, 31 May 2000; UW 111862, 66 mm, 52.5987 8 N, 169.3605 8 W, 231 m depth, F/ V Morning Star, cruise 2001-01, haul 1, benthic bag, J. W. Orr, 20 May 2001; UW 111864, 73.9 mm, 52.0722 8 N, 175.274 8 W, 88 m depth, F/ V Vesteraalen, cruise 2000-01, haul 104, benthic bag, W. C. Flerx, 15 June 2000; UW 111870, 77.9 mm, 52.3430 8 N, 179.8847 8 W, 159 m depth, F/ V Dominator, cruise 1997-01, haul 164, 21 July 1997; UW 113665, 4, 55.5–74.7 mm, 52.1634 8 N, 179.4879 8 E, 242 m depth, F/ V Vesteraalen, cruise 2002-01, haul 176, benthic bag, R. N. Clark, 13 July 2002; UW 113666, 69.7 mm, 52.2748 8 N, 172.9359 8 W, 291 m depth, F/ V Vesteraalen, cruise 2000-01, haul 65, benthic bag, 3 June 2000; UW 113698, 73 mm, 52.2754 8 N, 170.5991 8 W, 235 m depth, F/ V Sea Storm, cruise 2004-01, haul 34, J. W. Orr, 14 June 2004; UW 113701, 67.7 mm, 51.9059 8 N, 178.2489 8 E, 249 m depth, F/ V Vesteraalen, cruise 2002-01, haul 152, benthic bag, R. N. Clark, 6 July 2002; UW 113703, 70 mm, 53.7028 8 N, 167.3344 8 W, 88 m depth, F/ V Morning Star, cruise 2002-01, haul 5, J. W. Orr, 27 May 2002; UW 113705, 2, 58.7 –62.0 mm, 51.4255 8 N, 178.8431 8 E, 197 m depth, F/ V Gladiator, cruise 2004-01, haul 160, benthic bag, G. C. Jensen, 15 July 2004; UW 113711, 66.8 mm, 51.6034 8 N, 176.4098 8 W, 237 m depth, F/ V Sea Storm, cruise 2002-01, haul 87, J. W. Orr, 3 July 2002; UW 113712, 67.6 mm, 51.6151 8 N, 178.445 8 W, 149 m depth, F/ V Vesteraalen, cruise 2002-01, haul 114, benthic bag, R. N. Clark, 24 June 2002; UW 117177, 90.5 mm, 52.3675 8 N, 171.2463 8 W, 320 m depth, F/ V Gladiator, cruise 2006-01, haul 39, benthic bag, J. W. Orr, 16 June 2006; UW 117243, 3, 53–80 mm, 52.6466 8 N, 170.2027 8 W, 229 m depth, F/ V Gladiator, cruise 2006-01, haul 35, benthic bag, J. W. Orr, 15 June 2006; UW 117558, 66 mm, 52.9288 8 N, 170.4111 8 W, 221 m depth, F/ V Sea Storm, cruise 2006-01, haul 29, B. Knoth, 14 June 2006; UW 119399, 65.4 mm, 52.1428 8 N, 175.2807 8 W, 208 m depth, F/ V Gladiator, cruise 2006-01, haul 66, benthic bag, J. W. Orr, 24 June 2006; UW 154479, 54.4 mm, 54.2021 8 N, 166.1854 8 W, 164 m depth, F/ V Sea Storm, cruise 2010-01, haul 8, J. W. Orr, 11 June 2010; UW 154876, 4, 32–78 mm, 52.0271 8 N, 177.7521 8 W, 192 m depth, F/ V Sea Storm, cruise 2014-01, haul 153, 17 July 2014; UW 154881, 72.5 mm, 52.036 8 N, 179.3053 8 E, 277 m depth, F/ V Sea Storm, cruise 2012-01, haul 137, W. C. Flerx, 12 July 2012; UW 155474, 94.7 mm, 52.3431 8 N, 170.7108 8 W, 223 m depth, F/ V Sea Storm, cruise 2002-01, haul 199, R. C. Harrison, 3 August 2002; UW 155477, 2, 81.3–85.1 mm, 52.4024 8 N, 171.8333 8 W, 270 m depth, F/ V Sea Storm, cruise 2002-01, haul 213, R. C. Harrison, 8 August 2002; UW 155514, 70.5 mm, 52.3519 8 N, 174.5369 8 W, 109 m depth, F/ V Sea Storm, cruise 2002-01, haul 4, benthic bag, K. E. Pearson, 13 June 2002; UW 155515, 57.2 mm, 52.4212 8 N, 170.2785 8 W, 211 m depth, F/ V Dominator, cruise 2000-01, haul 43, benthic bag, J. W. Orr, 29 May 2000; UW 155517, 61.6 mm, 52.6475 8 N, 170.2191 8 W, 226 m depth, F/ V Dominator, cruise 2000-01, haul 40, benthic bag, 27 May 2000; UW 156091, 2, 62–70.5 mm, 52.4766 8 N, 170.1449 8 W, 183 m depth, F/ V Sea Storm, cruise 2012-01, haul 44, D. Drumm, 18 June 2012; UW 156094, 59 mm, 54.5625 8 N, 159.0424 8 W, 133 m depth, F/ V Alaska Provider, cruise 2013-01, haul 72, P. Von Szalay, 15 June 2013; UW 156095, 71 mm, 53.0181 8 N, 170.3998 8 W, 297 m depth, F/ V Sea Storm, cruise 2012-01, haul 31, D. Drumm, 13 June 2012; UW 157674, 71.2 mm, 51.3651 8 N, 178.9066 8 E, 165 m depth, F/ V Alaska Provider, cruise 2016-01, haul 135, benthic bag, 8 July 2016; UW 157675, 67.2 mm, 51.4295 8 N, 178.8275 8 E, 214 m depth, F/ V Alaska Provider, cruise 2016-01, haul 138, benthic bag, 9 July 2016; UW 158239, 80 mm, 52.9358 8 N, 170.4509 8 W, 250 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 37, 17 June 2012; UW 158243, 58.7 mm, 52.2657 8 N, 170.8021 8 W, 226 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 45, 18 June 2012; UW 158244, 63.5 mm, 52.9825 8 N, 170.3857 8 W, 218 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 36, 17 June 2012; UW 158246, 65.5 mm, 58.7219 8 N, 151.9983 8 W, 146 m depth, F/ V Morning Star, cruise 2001-01, haul 264, 22 July 2001; UW 158247, 79.1 mm, 52.288 8 N, 170.7933 8 W, 219 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 44, 18 June 2012; UW 158253, 51.7 mm, 51.8588 8 N, 178.4628 8 E, 218 m depth, F/ V Sea Storm, cruise 2012-01, haul 147, 15 July 2012; UW 158291, 2, 73.8–78 mm, 52.1823 8 N, 172.4394 8 W, 190 m depth, F/ V Sea Storm, cruise 2012-01, haul 75, D. Drumm, 25 June 2012; UW 158411, 59.9 mm, 52.4759 8 N, 170.7595 8 W, 258 m depth, F/ V Ocean Explorer, cruise 2012-01, haul 46, 19 June 2012; UW 158412, 2, 64.0– 81.2 mm, 51.6261 8 N, 178.439 8 W, 178 m depth, F/ V Ocean Explorer, cruise 2018- 01, haul 107, N. E. Roberson, 5 July 2018; UW 159755, 53.3 mm, 52.9582 8 N, 170.4005 8 W, 220 m depth, F/ V Morning Star, cruise 2002-01, haul 51, benthic bag, 4 June 2002; UW 159757, 27 mm, 51.6022 8 N, 177.5741 8 W, 226 m depth, F/ V Dominator, cruise 2000-01, haul 116, benthic bag, K. E. Pearson, 19 June 2000; UW 159759, 67 mm, 53.1303 8 N, 169.9617 8 W, 433 m depth, F/ V Vesteraalen, cruise 2000-01, haul 35, 26 May 2000; UW 159761, 2, 85–89 mm, 51.8454 8 N, 173.8995 8 W, 246 m depth, F/ V Sea Storm, cruise 2004-01, haul 78, R. N. Clark, 28 June 2004; UW 159774, 76.4 mm, 51.8653 8 N, 178.3737 8 E, 222 m depth, F/ V Sea Storm, cruise 2014-01, haul 147, G. R. Hoff, 16 July 2014; UW 159775, 76.8 mm, 51.6249 8 N, 178.4132 8 E, 154 m depth, F/ V Sea Storm, cruise 2014-01, haul 133, G. R. Hoff, 12 July 2014; UW 159776, 66.1 mm, 52.0362 8 N, 178.0337 8 E, 198 m depth, F/ V Sea Storm, cruise 2004-01, haul 140, R. N. Clark, 10 July 2004; UW 159777, 77.6 mm, 52.2307 8 N, 175.242 8 E, 146 m depth, F/ V Sea Storm, cruise 2002-01, haul 138, J. W. Orr, 16 July 2002; UW 159778, 75 mm, 51.6843 8 N, 175.5556 8 E, 180 m depth, F/ V Vesteraalen, cruise 2002-01, haul 158, benthic bag, R. N. Clark, 7 July 2002; UW 159779, 76.5 mm, 52.3032 8 N, 175.815 8 E, 243 m depth, F/ V Vesteraalen, cruise 2002-01, haul 169, benthic bag, R. N. Clark, 10 July 2002.
Diagnosis.— Careproctus candidus is distinguished from all described species of Careproctus by having the following combination of characters: dorsal fin with anterior lobe of one to three longer rays followed by one to three shortened rays forming a distinct notch, pupil a horizontal ellipse or slit, variegated coloration of reddish pink and white, and prickles often present. It is similar to other species in the subgenus Temnocora (Orr et al., 2019), but it is further distinguished from those species by the presence of a dorsal-fin lobe defined by a distinct notch (lacking in all other members of the subgenus), as well as in having a lower total vertebral count than C. comus and C. faunus (46–51 vs. 56–61 and 52–56 for C. comus and C. faunus, respectively). It is most similar to Careproctus klisi, new species, but it differs in having a more slender body at anal-fin origin 58.2–92.3 (mean 71.2) % HL (vs. 75.6–100.0 [mean 87.3] % HL in C. klisi, new species) and more slender body at midpoint of anal fin 23.6–42.9 (mean 30.8) % HL (vs. 36.1–53.1 [mean 42.2] % HL in C. klisi, new species), as well a distinct dorsal-fin notch (vs. notch lacking in C. klisi, new species).
Description.— Body robust, deepest at dorsal-fin origin, tapering posteriorly, rounded in cross section anteriorly, compressed posteriorly; depth at dorsal-fin origin 76.5–110.1 (89.4) % HL; depth at anal-fin origin 58.2–92.3 (75.9) % HL; depth at midpoint of anal fin 23.6–42.9 (27.7) % HL. Head large and robust, its length 25.7–31.0 (28.0) % SL, dorsal profile rounded from nape to snout. Snout blunt, slightly projecting anterior to lower jaw. Mouth subterminal, maxilla 34.0–51.7 (40.6) % HL, extending to anterior edge of pupil or to mid-orbit, oral cleft extending to anterior rim of orbit or to a point slightly anterior to orbit. Lower jaw slightly inferior, premaxillary tooth plates matching mandibular tooth plates.
Both premaxillary and mandibular teeth trilobed in 8–12 oblique rows of 4–10 teeth. Diastemata absent at symphysis of upper and lower jaws. Orbit large, 31.2–47.6 (31.2) % HL, dorsal margin below dorsal contour of head, suborbital depth to maxilla 10.0–60.4 (60.4) % OL; pupil a horizontal ellipse to a horizontal slit. Interorbital space moderate, fleshy distance 12.9–38.7 (26.5) % HL, bony distance 5.5–16.7 % HL. Snout ranging from shorter than to about equal to orbit length, 59.2–109.4 (109.4) % OL, 21.6–38.3 (34.1) % HL. Nostril single, opening flush with snout or in a tube reaching to 5.0 (flush with snout) % HL.
Pores of cephalic lateralis of moderate size: pore pattern 2- 6-7-2; chin pores two. Free neuromasts (Andriashev and Stein, 1998) about 4–5, small and difficult to discern, originating above gill slit and extending to a level at mid-body to a distance about level with anus.
Gill opening small, 14.0–24.9 (19.4) % HL, upper margin level with upper rim of orbit or mid-orbit, extending ventrally to just above pectoral fin or to pectoral-fin ray one, two, or three. Opercular flap angular. Gill rakers 6–10, short, blunt.
Dorsal-fin rays 37–49 (48; Table 1), all rays simple. Anterior dorsal-fin lobe present, composed of about seven rays: first three to four rays longer, rays four or five through seven shortened to form a distinct notch, rays eight and beyond lengthening (Fig. 3A). Rays of anterior dorsal-fin lobe variably exserted, ranging from not exserted to exserted for up to half their length (Fig. 3A, B). Anteriormost dorsal-fin pterygiophore inserted between neural spines two and three, bearing a single small ray. Anterior rayless pterygiophore absent. Predorsal length 24.3–32.5 (28.8) % SL.
Anal-fin rays 35–41 (40; Table 1), anal-fin pterygiophores anterior to first haemal spine one to three, each bearing a single ray, or absent (one). All rays simple. Anal-fin origin below vertebrae 10–12 (below caudal vertebrae 1–3; below caudal vertebra two in holotype), preanal length 34.7–46.9 (37.9) % SL.
Pectoral fin shallowly to moderately notched, with 31–41 rays (35; Table 1). Upper lobe of 23–32 (23) rays extending to anal-fin ray one to seven, dorsalmost rays lengthening to rays 6–8, more ventral rays gradually shortening to shortest ray of notch. Dorsal margin crenulate, fin margins more emarginate ventrally. Lower lobe with 6–12 (12) rays, extending to just past anus or beyond to just before anal-fin origin; dorsal rays of lower lobe gradually lengthening to thicker and fleshy rays 2–3, ventral rays gradually shortening to ventralmost ray near pectoral symphysis. Tips of rays 10–70 % free of membrane, rays of lower lobe more strongly exserted. Rays in notch slightly more widely spaced than rays of lobes. Uppermost pectoral-fin ray level with region between mid-orbit and ventral rim of orbit.variegated white variegated white variegated brown variegated red, variegated red, variegated pinkish / mottled red and and pink and pink and white white, and gray white, and gray yellowish and pale with golden white slash along body
Proximal pectoral radials four (3 þ 1), robust; proximal radial one notched, radial two rounded (6 specimens, Fig. 4A, B) or notched (1 specimen, Orr and Maslenikov, 2007), radial three rounded (5 specimens, Fig. 4A) or notched (2 specimens, Fig. 4B), radial four a rounded square (Fig. 4A, B). Interradial fenestrae one (5 specimens, Fig. 4A) or two (2 specimens, Fig. 4B), one always oval, extending between scapula and proximal radial one, when two fenestrae present, second small, slender, extending between proximal radial two and three (Fig. 4B). Scapula broadly Y-shaped with robust helve; coracoid with triangular head and long helve. Anterodorsal hook present, distinctly pointed (Fig. 4A) or small and rounded (Fig. 4B). Distal radials present at base of rays two to 29–34, ventral 6–9 rays articulating directly with fibrocartilage pad.
Pelvic disk moderately large, length 26.4–39.4 (30.0) % HL, round, typically slightly longer than wide, width 23.2–38.8 (29.4) % HL, anterior lobe moderately developed, flat with margins often slightly upturned, distance from tip of upper jaw to pelvic disk 11.8–20.2 (13.5) % SL. Anus closer to pelvic disk than to anal-fin origin, 4.2–20.2 (11.8) % HL from pelvic disk, distance from tip of upper jaw to anus 21.9–33.2 (25.4) % SL.
Principal caudal-fin rays 10–11 (10; Table 1), dorsal procurrent rays 1 to 3 (2), ventral procurrent rays 0 to 3 (1). Membrane of posterior dorsal-fin rays attached for shorter distance to caudal fin than anal-fin rays: dorsal-fin rays attached to caudal fin 12.9–37.7 (28.6) % CL; anal-fin rays 19.8–48.5 (19.8) % CL. Depth at base of caudal fin 9.4–19.0 % CL.
Skin thin and somewhat loose in preservation, prickles present, ranging from very few to many. Prickles densest in patches on head, on fin membrane of anterior dorsal-fin lobe, along base of median fins, and on caudal peduncle, otherwise widely scattered. Many specimens with few prickles present, with two or three in otherwise dense patch areas. Pyloric caeca 16–24, length about 25% HL.
Vertebrae 46–51 (51), precaudal 9–10 (10), caudal 36–42 (41; Table 1). Pleural ribs 1–3 (3), present on vertebrae 8–10, all slender, those on vertebra nine long, slightly more robust, others short when present. Hypural plate composed of dorsal and ventral plates divided by slight notch in plate. Single epural present.
Coloration.— Body variegated pink and white in life, head with white blotch on cheek, white blotches often scattered over body (Fig. 1). Median fins with darker reddish-orange to brownish coloring especially posteriorly. Eye greenish gold in life with pupil a horizontal ellipse to horizontal slit. Eye black in preservation. Body pale in preservation, sometimes with scattered melanophores along posterior portions of median fins (Fig. 2A). Peritoneum, orobranchial cavity, stomach, intestines, pyloric caeca, and urogenital papilla pale.
Life history.— The largest specimen examined was a ripe female 94.7 mm (UW 155474), yolked egg diameter 2.7 mm. The smallest female with yolked eggs was 65.5 mm (UW 158246). Two smaller, spent females 54.4–62.0 mm were also found. Right ovaries were dissected from two females with yolked eggs; five to eight yolked eggs (1.9–3.7 mm diameter) were present with a roughly equal amount of developed but unyolked eggs (0.6 mm diameter) and with many small immature eggs present (0.2–0.3 mm diameter). One ripe male was found 73.8 mm (UW 158291).
Distribution.— Based on our material, Careproctus candidus ranges from Attu Island in the Aleutian Islands to the northern Gulf of Alaska, north of Kodiak Island (Fig. 5). Collection depths range from 88 to 433 m. The species is also reported from the western Pacific region off southeastern Kamchatka and the northern Kuril Islands (Sheiko and Fedorov, 2000; Mecklenburg et al., 2002) and to depths of 64 and 518 m (Mecklenburg et al., 2002). Although these records are likely of members of the subgenus Temnocora, we have not confirmed the identification of these specimens as C. candidus.
Etymology.— Derived from the Latin candidus literally meaning ‘‘shining white’’ or loosely as ‘‘transcendently beautiful,’’ likely in reference to the white blotching and variegated reddish coloring of the species.
Remarks.— Three specimens (UW 155512, UW 155513, UW 158398) may represent an undescribed species. All three are ripe or spent females and the two ripe females were smaller (62.5–64.0 mm SL) than the smallest ripe female of C. candidus examined (65.5 mm SL). They differ from C. candidus posteriorly in having a more rapidly tapering profile, becoming more slender at the midpoint of the anal fin 20.9–23.0 % HL (vs. 23.6–42.9 % HL in C. candidus sensu stricto), and a shorter predorsal length 77.0–90.2 (vs. 84.5– 104.9 % HL). We postpone a description of this species until more material becomes available.
In addition to pectoral-girdle morphology, C. candidus exhibited diversity in other characters. The rays comprising the dorsal-fin lobe, anterior to the dorsal notch, were variably exserted, ranging from no exsertion to being exserted for up to half the ray length. The paratypes for C. candidus all have an intermediate level of exsertion with the fin margin being crenulate and just the tips of the rays being exserted. Prickles were present, but the amount varies, with some specimens having prickles widely scattered over the body, some having prickles isolated in distinct, dense patches, and some having only a few prickles in one of the patch locations. Previously, prickles were not known to occur in C. candidus, but this may have been due to the prickles being missed during the original description as the types possess only a few prickles each. These ranges of variation in character states are not seen in other members of the subgenus Temnocora. Additionally, Orr et al. (2019: fig. 10, appendix table 1) reported molecular diversity in cytochrome c oxidase subunit I (COI) sequence data among specimens identified as C. candidus, although we found no morphological differences between these specimens. This morphological and genetic diversity suggests unrecognized species diversity may be present within C. candidus.
description: Published as part of Gardner, Jennifer R., Orr, James W. & Tornabene, Luke, 2023, Two New Species of Snailfishes (Cottiformes: Liparidae) from the Aleutian Islands, Alaska, and a Redescription of the Closely Related Careproctus candidus, pp. 54-71 in Ichthyology & Herpetology 111 (1) on pages 55-61, DOI: 10.1643/i2022009, http://zenodo.org/record/7847025