Careproctus bromius, Gardner & Orr & Tornabene, 2023

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, Ichthyology & Herpetology 111 (1), pp. 54-71 : 65-67

Careproctus bromius , new species

urn:lsid:zoobank.org:act:4CD9E9D4-AC4B-4336-A673-11D944483DBB

Boisterous Snailfish

Figures 3D , 4E, 4F , 5 , 8 , 9 ; Tables 1 , 2; Supplemental Table A

Holotype.— UW 155719 , 43.5 mm, ripe female, Aleutian Islands , Seguam Pass, 52.2629 8 N, 172.8827 8 W, 158 m depth, F/ V Gladiator , cruise 2006-01, haul 52, J. W. Orr, 21 June 2006.

Paratypes.— 11 specimens, 27–46.9 mm. SIO 22-2 (ex UW 158418 ), 35.3 mm, 54.0916 8 N, 166.2622 8 W, 80 m depth, F/ V Vesteraalen, cruise 2002-01, haul 26, 23 May 2002 ; UAM 4012 (ex UW 158399 ), 38.1 mm, 51.5981 8 N, 179.1703 8 W, 224 m depth, F/ V Dominator , cruise 2000-01, haul 138, benthic bag, K. Pearson, 24 June 2000 ; USNM 439016 (ex UW 158416 ), 38.6 mm, 51.9106 8 N, 173.7578 8 W, 119 m depth, F/ V Ocean Explorer , cruise 2018-01, haul 82, N. E. Roberson, 30 June 2018 ; UW 113670 , 27 mm, 51.9376 8 N, 176.8389 8 W, 87 m depth, F/ V Dominator , cruise 2000-01, haul 112, benthic bag, K. Pearson, 17 June 2000 ; UW 155709 , 2 , 40.5 –42.0 mm, 51.6163 8 N, 178.1877 8 W, 126 m depth, F/ V Ocean Explorer , cruise 2012-01, haul 117, J. W. Orr, 6 July 2012 ; UW 158400 , 44.2 mm, 51.5001 8 N, 178.6552 8 W, 232 m depth, F/ V Vesteraalen , cruise 2000-01, haul 123, benthic bag, W. C. Flerx, 21 June 2000 ; UW 158401 , 38.5 mm, 51.5078 8 N, 178.5773 8 W, 168 m depth, F/ V Sea Storm , cruise 2014-01, haul 106, G. R. Hoff, 5 July 2014 ; UW 158413 , 46.9 mm, 52.0997 8 N, 175.2914 8 W, 105 m depth, F/ V Alaska Provider , cruise 2014-01, haul 98, P. Logan, 4 July 2014 ; UW 158415 , 39.0 mm, 51.6083 8 N, 177.6106 8 W, 125 m depth, F/ V Ocean Explorer , cruise 2018-01, haul 97, N. E. Roberson, 3 July 2018 ; UW 158417 , 35.1 mm, 51.6177 8 N, 178.1883 8 W, 122 m depth, F/ V Ocean Explorer , cruise 2018-01, haul 110, N. E. Roberson, 6 July 2018 .

Diagnosis.— Careproctus bromius is distinguished from described species of Careproctus by having the following combination of characters: low counts of median-fin rays (dorsal 38–42, anal 32–37) and vertebrae (44–47), body coloration of variegated light brown and pale with white cheek blotch, anterior dorsal-fin lobe absent, anteriormost dorsal-fin rays very short or embedded in skin, and prickles absent. It is most similar to C. iacchus in overall size, variegated body coloring, and in having a white cheek blotch ( Kai et al., 2018). It can be distinguished from C. iacchus in having 32–37 anal-fin rays (vs. 39–40 in C. iacchus ), 44–47 vertebrae (vs. 49–52), a larger OL 31.1–46.5 % HL (vs. 24.3–26.6 % HL), and a pectoral fin with a shallow notch (vs. no notch). It is similar to C. staufferi in meristic counts but can be distinguished based on coloration (variegated brown vs. brick red with golden slash at mid-body). It is also similar to C. candidus , from which it can be distinguished by lacking a dorsal-fin lobe (present in C. candidus ), having fewer vertebrae (44–47 vs. 46–51), a smaller size at maturity (smallest ripe female 35.3 mm vs. 65.5 mm), and distinct body coloration (variegated brown vs. mottled pink and white).

Description.— Body robust, deepest at nape, tapering posteriorly, rounded in cross section anteriorly, compressed posteriorly; depth at dorsal-fin origin 78.9–107.1 (78.9) % HL; depth at anal-fin origin 46.5–75.4 (62.6) % HL; depth at midpoint of anal fin 25.5–30.7 (27.6) % HL. Head large and robust, its length 25.4–28.3 (28.3) % SL, dorsal profile rounded from nape to snout. Snout blunt, slightly projecting anterior to lower jaw. Mouth subterminal, maxilla 44.6–66.4 (56.1) % HL, extending to anterior edge of pupil or to mid-orbit, oral cleft extending to anterior rim of orbit. Lower jaw slightly inferior, premaxillary tooth plates matching mandibular tooth plates. Both premaxillary and mandibular teeth trilobed in 8–10 oblique rows of 4–12 teeth. Diastemata absent at symphysis of upper and lower jaws. Orbit large, 31.1–46.5 (33.3) % HL, dorsal margin below dorsal contour of head, suborbital depth to maxilla 16.1–51.5 (24.4) % OL; pupil a horizontal ellipse to horizontal slit. Interorbital space flat, broad, fleshy distance 23.3–46.5 (41.5) % HL, bony distance 12.3–21.4 (17.9) % HL. Snout about equal to orbit length, 61.7–93.9 (85.4) % OL, 28.0–34.7 (28.5) % HL. Nostril single, in well-developed tube level with mid-orbit; nostril tube length 1.6–4.5 (4.1) % HL.

Pores of cephalic lateralis of moderate size; pore pattern 2- 6-7-2; chin pores two in a common wide oval depression, interspace equaling about one pore diameter. Free neuromasts 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, 14.4–22.8 (21.1) % HL, upper margin level with upper rim of orbit, extending ventrally to just above pectoral fin or to pectoral-fin ray one or two (entirely above pectoral fin). Opercular flap angular. Gill rakers 6–8, small, blunt.

Dorsal-fin rays 38–42 (41; Table 1 ), all rays simple. Anterior dorsal-fin lobe absent, first few rays very short or embedded in skin, rays longer posteriorly ( Fig. 3D ). Anteriormost dorsal-fin pterygiophore inserted between neural spines three and four, bearing a single small ray. Anterior rayless pterygiophore present, inserted between neural spines two and three. Predorsal length 26.9–31.5 (30.8) % SL.

Anal-fin rays 32–37 (34; Table 1 ), one anal-fin pterygiophore anterior to first haemal spine one, bearing a single ray or absent (one). All rays simple. Anal-fin origin below vertebrae 10–11 (caudal vertebra 1), preanal length 44.1– 49.9 (48.7) % SL.

Pectoral fin shallow to moderately notched, with 30–36 rays (33; Table 1 ). Upper lobe of 23–29 (26) rays extending beyond anus to anal-fin origin, 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 7–8 rays, extending to anus or just posterior; dorsal rays gradually lengthening to thicker and fleshy rays 2–3, ventral rays gradually shortening to ventralmost ray near pectoral symphysis. Tips of rays 10–50 % 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.

Proximal pectoral radials four (3 þ 1), robust; proximal radials one and two either notched and hourglass shaped (2 specimens, Fig. 4E ) or crescent shaped (1 specimen, Fig. 4F ), radial three crescent shaped, radial four a rounded square ( Fig. 4E, F ). Interradial fenestrae two (1 specimen, Fig. 4F ) or three (2 specimens, Fig. 4E ). Scapular fenestra elliptical, fenestra between proximal radials one and two elliptical or absent, fenestra extending between proximal radials two and three elongate ellipse. Scapula broadly Y-shaped with robust helve; coracoid with triangular head and long, thin helve. Anterodorsal hook present, small rounded. Distal radials present at base of rays 2 to 27–29, ventral 4–6 rays articulating directly with fibrocartilage pad.

Pelvic disk moderately large, length 32.1–40.2 (37.4) % HL, round, slightly longer than wide, width 30.2–38.4 (34.1) % HL, anterior lobe moderately developed, flat with margins often slightly upturned, distance from tip of upper jaw to pelvic disk 10.4–17.7 (13.1) % SL. Anus closer to pelvic disk than to anal-fin origin, 5.3–19.8 (18.7) % HL from pelvic disk, distance from tip of upper jaw to anus 24.2–32.5 (28.3) % SL.

Principal caudal-fin rays 11 (11; Table 1 ), dorsal procurrent rays 2 (2), ventral procurrent rays 1–2 (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 15.1–27.9 (27.9) % CL; anal-fin rays, 25.0–40.6 (34.4) % CL. Depth at base of caudal fin 11.5–22.0 (11.5) % CL.

Skin relatively thick, prickles absent. Pyloric caeca 13–16, length about 25% HL.

Vertebrae 44–47 (46), precaudal 9–10 (10), caudal 34–37 (36; Table 1 ). Pleural ribs 1–3 (2), present on vertebrae 8–10, anteriormost small when three present, others long and slender. Hypural plate composed of dorsal and ventral plates divided by slight notch in plate. Single epural present.

Coloration.— Body variegated light brown and pale in life, head with white blotch on cheek, white spots often scattered over body, concentrated dark band of pigment at base of caudal fin with small white band immediately following ( Fig. 8 ). Eye greenish to goldish in life with pupil a horizontal ellipse to horizontal slit. Body with scattered melanophores in preservation. Eye black in preservation ( Fig. 9A ). Peritoneum, orobranchial cavity, stomach, intestines, pyloric caeca, and urogenital papilla pale.

Life history.— The largest specimen examined was a ripe female 46.9 mm (UW 158413), with yolked egg diameter of 2.1 mm. The smallest female with yolked eggs was 35.3 mm (UW 158418). Ovaries were dissected from two females with yolked eggs. Females had five to nine yolked eggs (2.2–3.9 mm diameter), a roughly equal number of opaque, developed but unyolked eggs (0.7–0.9 mm diameter), and many small, translucent immature eggs (0.2–0.3 mm diameter). All males were mature or immature, none were ripe. The one mature male was 35.1 mm (UW 158417).

Distribution.— Careproctus bromius has been collected throughout the Aleutian Islands from north of Amatignak Island in the west to west of Akutan Island in the east ( Fig. 5 ). Collection depths range from 80 to 232 m.

Etymology.— Named after the Greek god, Bromius is an alternative epithet for Dionysus used in ancient Greece, sometimes referred to as the second Dionysus. Bromius was chosen to show the similarity of the new species to C. iacchu s, which was named for the god Iacchus, who was referred to as either a son of Dionysus or as the third Dionysus.

Figures

FIG. 3. Anterior dorsal-fin morphology in Careproctus candidus and two new species from the Aleutian Islands: (A) anterior dorsal-fin lobe with notch rays not exserted (based on C. candidus, USNM 74384, 60.7 mm, holotype); (B) anterior dorsal-fin lobe with notch rays partially exserted (based on C. candidus, UW 117177, 90.5 mm); (C) dorsal-fin lobe and notch absent, fin with anterior section of rays one to seven roughly equal in length (based on C. klisi, new species, UW 200421, 105.3 mm, holotype); (D) anterior dorsal-fin lobe and notch absent, rays short and embedded in skin (based on C. bromius, new species, UW 155719, 43.5 mm, holotype).

FIG. 4. Medial views of right pectoral girdles. (A) Careproctus candidus, UW 117243, 80 mm; (B) C. candidus, UW 154876, 1 of 4, 78 mm; (C) C. klisi, new species, paratype, UW 117553, 106.0 mm; (D) C. klisi, new species, paratype, UW 155491, 88.7 mm; (E) C. bromius, new species, paratype, UW 155709, 2 of 2, 42.0 mm, dashed lines indicate where coracoid was cut during dissection; (F) C. bromius, new species, paratype, UW 158400, 44.2 mm. Shaded areas represent cartilage.

FIG. 5. Distribution of Careproctus candidus (white), C. klisi, new species (gray), and C. bromius, new species (black), from the Aleutian Islands. Careproctus candidus distribution is based on material examined; the two new species, on all known material. Each symbol may represent more than one capture. Holotype localities represented by stars. Gray line represents the 200 m isobath.

FIG. 8. Careproctus bromius, new species: (A) UW 155719, 43.5 mm, holotype, ripe female, Aleutian Islands, Seguam Pass, 52.26298N, 172.88278W, 158 m depth; (B) UW 158401, 38.5 mm, ripe female, Aleutian Islands, Tanaga Pass, 51.50788N, 178.57738W, 168 m depth; (C) UW 155709, 2 of 2, 42.0 mm, ripe female, Aleutian Islands, Tanaga Pass, 51.61638N, 178.18778W, 126 m depth; (D) UW 158417, 35.1 mm, male, Aleutian Islands, Tanaga Pass, 51.61778N, 178.18838W, 122 m depth. All photographed before preservation.

FIG. 9. Careproctus bromius, new species, UW 155719, 43.5 mm, holotype, ripe female, Aleutian Islands, Seguam Pass, 52.26298N, 172.88278W, 158 m depth: (A) photographed after preservation; (B) illustration by Loren Eakins.