Allocareproctus ungak Orr & Busby, 2006, new species

Allocareproctus ungak new species

Whiskered Snailfish

(Figures 1-2, 4-6, 11, 13; Tables 1-4)

Allocareproctus jordani: Orr & Busby 2001 (in part; compared to Prognatholiparis ptychomandibularis).

Holotype: UW 111933, 91.0 mm, female, 52.3687ºN, 171.2406ºW, 323 m depth, 31 May 2000, M/V Dominator, cruise 2000-01, haul 51, benthic bag, J.W. Orr.

Paratypes: UW 112084, 4(55.0-106.9 mm), 52.3282ºN, 172.7468ºW, 444 m depth, 4 June 2000, F/V Vesteraalen, cruise 2000-01, haul 67, benthic bag, W.C. Flerx; UW 111934, 1(106 mm), 52.3282ºN, 172.7468ºW, 444 m depth, 4 June 2000, F/V Vesteraalen, cruise 2000-01, haul 67, W.C. Flerx; UW 111935, 2(97.3-98.4 mm), 52.3131ºN, 171.5057ºW, 445 m depth, 31 May 2000, M/V Dominator, cruise 2000-01, haul 54, benthic bag, J.W. Orr; UW 111929, 1(105.5 mm), 52.1920ºN, 171.6730ºW, 461 m depth, 6 August 2002, F/V Sea Storm, cruise 2002-01, haul 210, R.C. Harrison; UW 45239, 17(81.5-101.2 mm; 84.5 mm cleared and stained), 52.3184ºN, 172.7453ºW, 455 m depth, 22 June 1997, F/V Vesteraalen, cruise 1997-01, haul 58, W.C. Flerx; UW 111937, 1(87 mm), 52.5517ºN, 169.4788ºW, 330 m depth, 25 May 2003, F/V Northwest Explorer, cruise 2003-01, haul 6, J.W. Orr; UW 111933, 1(91 mm, in 95% ethanol), 52.3687ºN, 171.2406ºW, 323 m depth, 31 May 2000, M/V Dominator, cruise 2000-01, haul 51, J.W. Orr; UW 111938, 1(112 mm), 52.3687ºN, 171.2406ºW, 323 m depth, 31 May 2000, M/V Dominator, cruise 2000-01, haul 51, J.W. Orr; UW 45238, 3(72.1-91.7 mm), 52.3310ºN, 172.7470ºW, 441 m depth, 23 July 2002, F/V Sea Storm, cruise 2002- 01, haul 156, J.W. Orr; UW 111928, 2(85.8-93.2 mm), 52.3687ºN, 171.2406ºW, 323 m depth, 31 May 2000, M/V Dominator, cruise 2000-01, haul 51, benthic bag, J.W. Orr; UW 111927, 1(94.3 mm), 52.3732ºN, 171.3548ºW, 324 m depth, 10 August 2002, F/V Sea Storm, cruise 2002-01, haul 225, R.C. Harrison; USNM 385688, 3(97-115 mm), 52.5251ºN, 172.0747ºW, 364 m depth, 21 June 2004, F/V Sea Storm, cruise 2004-01, haul 66, J.W. Orr; USNM 385689, 3(62-78 mm), 52.3255ºN, 172.7466ºW, 450 m depth, 19 June 2004, F/V Sea Storm, cruise 2004-01, haul 60, benthic bag, J.W. Orr; CAS 223486, 7(91-107 mm), 52.3728ºN, 171.3587ºW, 318 m depth, 21 June 2004, F/V Gladiator, cruise 2004-01, haul 65, K.P. Maslenikov; UW 113675, 1(94.5 mm), 52.1932ºN, 171.6718ºW, 461 m depth, 20 June 2004, F/V Gladiator, cruise 2004-01, haul 58, K.P. Maslenikov; UW 113676, 1(129.3 mm), 52.9580ºN, 169.4346ºW, 429 m depth, 12 June 2004, F/V Gladiator, cruise 2004-01, haul 26, K.P. Maslenikov.

Diagnosis

Teeth strongly trilobed (Fig. 2E); nasal pore 1 with unpigmented papilla; peritoneum black; orobuccal valve with 1 finger-like projection; orobuccal cavity pale; gill rakers 7-11, short, blunt; interorbital papilla present or absent; pyloric caeca on right or left side; body red; iris silver gray.

Description

Body depth at pectoral-fin base 15.0-21.0 (19.5)%, at center of pelvic disk 16.6-22.9 (21.9)%, at anal-fin origin 18.2-25.2 (22.0)%. Predorsal length 25.9-29.7 (27.3)%. Preanal length 38.4-47.3 (43.1)%. Head large, width 11.8-20.4 (14.1)%, length 23.9-27.3 (24.7)%. Interorbital width 4.9-8.0 (5.7)%, about equal to orbit length. Snout 6.8-9.3 (7.9)%. Mouth small, maxilla 9.0-12.1 (10.1)%, extending to midorbit. Teeth strongly trilobed (Fig. 2E), in a broad band of 8-12 oblique rows of 5-16 teeth per row, band narrowing posteriorly to 2- 3 rows on premaxilla and to a short uniserial row of 6 teeth on dentary. Orbit large, diameter 5.2-7.0 (6.2)%.

Papillae strong, present on many pores: present on nasal pore 1, absent from nasal pore 2; present on maxillary pores 4-6, often present on pores 2-3 (4-6); present on preoperculomandibular pores 5-6, often present also on pore 7 (5-7); present on suprabranchial pores 1-2 (Fig. 4F). Interorbital papilla present or absent (present in holotype). Papillae unpigmented. Cephalic free neuromasts reduced and nearly indiscernible over the interorbit and nape.

Gill opening small, 4.9-7.8 (7.6)%, entirely above pectoral fin or extending to pectoral-fin ray 3 (1). Gill rakers on anterior arch 7-11 (10), short and blunt. Central projection of orobuccal valve a moderately elongate single lobe.

Dorsal-fin rays 39-42 (41), tips of anterior 4-6 rays projecting from fin membrane, anteriormost rays about 30% free from membrane, succeeding rays less so; posteriormost ray attached membranously to dorsalmost caudal-fin ray for 2.3-5.8 (4.0)%. Anal fin with 33-35 (34) rays, posteriormost ray membranously attached to ventralmost caudal-fin ray for 3.0-5.9 (3.6)%. One or two (2) anal-fin pterygiophores and associated rays anterior to first haemal spine.

Pectoral-fin rays 35-40 (37) in two lobes, separated by shallow notch, 8-10 (9) rays in lower lobe. Dorsalmost ray at level of ventral rim of orbit. Upper lobe rounded, extending to anal-fin origin, length 16.0-20.0 (17.1)%, with rays 5-6 (5) longest; length of shortest notch ray 5.8-10.5 (6.0)%; length of lower lobe 14.4-19.8 (15.9)%, extending between posterior margin of pelvic disk and anus, with ray 3 longest, rays 4-10 shortening ventrally.

Pelvic disk large, length 8.6-11.8 (8.8)%, width 7.1-11.1 (8.2)%. Distance from disk to anus 1.5-5.5 (4.8)%, about 13-55 (55)% DL, distance from anus to anal-fin origin 6.7-18.8 (13.4)%, about 50-200 (152.5)% DL. Urogenital papilla conical, relatively long, 4-96.5 (6.0)% DL, unpigmented. Pyloric caeca about 20, primarily on right side of body, finger-like, long, about 25-50 (40)% HL.

Caudal fin slightly rounded, 13.0-17.1 (14.4)%, depth at hypural plate 3.3-5.2 (4.2)%, with principal rays 11-13 (12), dorsal principal rays 5-6 (5); ventral principal rays 7-8 (7). Dorsal procurrent rays 2, borne on epural and posteriormost neural spine; ventral procurrent ray 1, borne on expanded posteriormost haemal spine. Vertebrae 45-47 (46), abdominal vertebrae 10-11 (11), caudal vertebrae 34-36 (35).

Body in life uniform light red, scattered speckling rarely present at origin of dorsal fin; iris silver gray. Color in alcohol pale, with pigment absent from cephalic papillae and rarely present at origin of dorsal fin. Peritoneum black; orobranchial cavity pale.

Largest specimen examined a 129.3 mm male (UW 113676). Smallest female with yolked eggs 85 mm; smallest male with enlarged, swollen testes 95 mm.

Range

Allocareproctus ungak has been collected only in the Aleutian Islands, from Seguam Pass to the Islands of Four Mountains, at depths of 318 to 461 m (Fig. 11).

Etymology

The specific epithet “ungak” is taken from the Alutiiq word for “whiskers” an allusion to the many papillae associated with cephalic pores. It is to be treated as a noun in apposition.

Comparisons

Allocareproctus ungak is most similar to A. unangas, which also has trilobed teeth (Fig. 2D-E) and a uniform red body. It is distinguished from A. unangas by the presence of a papilla on nasal pore 1 and higher number of pores with associated papillae (Fig. 4). Pyloric caeca are longer and typically on the right side of the body, unlike A. unangas in which they are shorter and on the left. For meristic and morphometric differences from other species of Allocareproctus, see species accounts above.