Allocareproctus kallaion, Orr & Busby, 2006

Orr, James Wilder & Busby, Morgan Scott, 2006, Revision of the snailfish genus Allocareproctus Pitruk & Fedorov (Teleostei: Liparidae), with descriptions of four new species from the Aleutian Islands, Zootaxa 1173, pp. 1-37 : 23-27

Allocareproctus kallaion new species

Combed Snailfish

( Figures 1–6 , 9 , 12–13 ; Tables 1–4 )

Holotype: UW 112244, 157.0 mm, female, 52.3405ºN, 172.7455ºW, 441 m depth, 31 May 2002, F/ V Morning Star, cruise 2002­01, haul 32, J.W. Orr.

Paratypes: UW 112243, 3 (145.0–190.0 mm), 52.3732ºN, 171.3548ºW, 324 m depth, 10 August 2002, F/V Sea Storm, cruise 2002­01, haul 225, R.C. Harrison ; UW 112235, 1 (162.0 mm), 52.3796ºN, 170.6611ºW, 278 m depth, 31 May 2000, F/V Vesteraalen, cruise 2000­01, haul 51, W.C. Flerx ; UW 112241, 3 (108.0–167.0 mm), 52.331ºN, 172.7470ºW, 441 m depth, 23 July 2002, F/V Sea Storm, cruise 2002­01, haul 156, J.W. Orr ; UW 112237, 1 (152.9 mm), 52.2383ºN, 172.1247ºW, 357 m depth, 29 July 2002, F/V Sea Storm, cruise 2002­01, haul 167, benthic bag, R.C. Harrison ; UW 112236, 2 (129.0–133.0 mm; 129.0 mm cleared and stained), 52.4877ºN, 172.5677ºW, 419 m depth, 26 June 1997, M/V Dominator, cruise 1997­01, haul 71, R.C. Harrison ; UW 112242, 3 (139.5–176.0 mm), 52.3217ºN, 172.7447ºW, 458 m depth, 16 June 1994, F/V Pacific Knight, cruise 1994­01, haul 54 ; UW 112278, 8 (109.8–157.0 mm), 52.3405ºN, 172.7455ºW, 441 m depth, 31 May 2002, F/V Morning Star, cruise 2002­01, haul 32, J.W. Orr ; UW 112239, 1 (161.0 mm), 52.3282ºN, 172.7468ºW, 444 m depth, F/V Vesteraalen, cruise 2000­01, haul 67, W.C. Flerx ; UW 112238, 2 (110.8–119.5 mm), 52.3282ºN, 172.7468ºW, 444 m depth, 4 June 2000, F/V Vesteraalen, cruise 2000­01, haul 67, benthic bag, W.C. Flerx ; UW 113691, 16 (72.0–170.0 mm), 52.3255ºN, 172.7466ºW, 450 m depth, 19 June 2004, F/V Sea Storm, cruise 2004­01, haul 60, J.W. Orr; USNM 385683, 2 (113.0–165.0 mm), 52.3255ºN, 172.7466ºW, 450 m depth, 19 June 2004, F/V Sea Storm, cruise 2004­01, haul 60, benthic bag, J.W. Orr; USNM 385684, 1 (156.0 mm), 52.4888ºN, 172.5564ºW, 397 m depth, 20 June 2004, F/V Sea Storm, cruise 2004­01, haul 61, J.W. Orr; CAS 223481, 1 (146.0 mm), 52.5251ºN, 172.0747ºW, 364 m depth, 21 June 2004, F/V Sea Storm, cruise 2004­01, haul 66, J.W. Orr; CAS 223482, 1 (195.0 mm), 52.2102ºN, 172.2060ºW, 341 m depth, 23 June 2004, F/V Sea Storm, cruise 2004­01, haul 73, J.W. Orr .

Diagnosis

Teeth simple ( Fig. 2C ); nasal pore 1 with pigmented papilla; peritoneum black; orobuccal valve with 4–6 finger­like projections; orobuccal cavity dark; gill rakers 14–18, stout, with strong spines at tip; interorbital papilla absent; body blotchy red, darker gray anteriorly; iris silver gray.

Description

Body depth at pectoral­fin base 11.8–18.6 (15.4)%, at center of pelvic disk 13.8–21.2 (18.0)%, at anal­fin origin 14.0–22.0 (18.8)%. Predorsal length 22.7–28.6 (25.2)%. Preanal length 38.8–47.0 (43.4)%.

Head large, width 12.4–19.6 (18.4)%, length 21.7–24.3 (22.4)%. Interorbital width 4.3–7.7 (5.1)%. Snout 5.5–8.8 (6.9)%. Mouth small, maxilla 7.5–11.3 (11.3)%, extending to anterior portion of orbit. Teeth simple, recurved, rarely with weak shoulders ( Fig. 2C ), in a narrow band of 4–12 oblique rows of 5–10 teeth per row in all except the posterior outer row; outer row of 34 teeth forming comb­like series. In all except outer row, middle teeth of each row largest; in outer row, first 20 teeth equally sized, succeeding teeth gradually smaller posteriorly. Orbit large, diameter 5.3–7.3 (6.1)%.

Papillae present on many pores: present on nasal pore 1, absent from nasal pore 2; present on maxillary pores 2–6, rarely present on pore 1 (2–6); present on preoperculomandibular pores 5–7, often present also on pore 4 (5–7); present on suprabranchial pores 1–2 (Fig. 4D). Papillae with slight pigment or unpigmented. Interorbital papilla absent. Cephalic free neuromasts large and profuse to nearly indiscernible over the interorbit and nape.

Gill opening small, 4.6–6.7 (5.6)%, entirely above pectoral fin. Gill rakers on anterior arch 14–18 (16), stout with strong spines at tip. Orobuccal valve with 4–6 (4) finger­like lobes, central lobe largest, other lobes successively smaller ( Fig. 12B ).

Dorsal­fin rays 42–45 (44), 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 caudal­fin ray for 2.0–4.4 (2.7)%. Anal fin with 33–37 (36) rays, posteriormost ray membranously attached to ventralmost caudal­fin ray for 2.6–5.1 (3.4)%. One to three (2) anal­fin pterygiophores and associated rays anterior to first haemal spine.

Pectoral­fin rays 36–40 (37) in two lobes separated by shallow notch, 9–12 (10) rays in lower lobe. Dorsalmost ray at level just below ventral rim of orbit. Upper lobe rounded, extending to anal­fin origin, length 15.8–20.1 (17.6)%, with rays 6–7 (6) longest; length of shortest notch ray 4.3–9.5 (6.7)%; length of lower lobe 13.3–20.2 (15.0)%, extending between posterior margin of pelvic disk and anus, with ray 3 longest, rays 9–12 shortening ventrally.

Pelvic disk large, length 8.0–9.7 (8.5)%, width 7.1–8.8 (7.8)%. Distance from disk to anus 2.7–9.4 (6.2)%, about 28–105 (73.7)% DL, distance from anus to anal­fin origin 11.6–18.9 (16.6)%, about 125–225 (196)% DL. Urogenital papilla conical, short, about 10–25 (11.2)% DL when protruded, unpigmented. Pyloric caeca about 22–27 (22), on right side of body, finger­like, long, 25–50 (48.4)% HL.

Caudal fin slightly rounded, 12.8–17.1 (14.3)%, depth at hypural plate 2.7–4.6 (2.9)%, with principal rays 11–14 (12), dorsal principal rays 5–7 (5), ventral principal rays 6–7 (7). Dorsal procurrent rays 2–3 (2), borne on epural and posteriormost neural spine; ventral procurrent ray 1–2 (1), borne on expanded posteriormost haemal spine. Vertebrae 45–49 (49), abdominal vertebrae 12, caudal vertebrae 33–37 (37).

Color in life light red, with darker red blotches scattered over body, dark speckling at origin of dorsal fin, anterior part of body blue­gray, posterior part of body blotchy red; iris silver gray. Color in alcohol dark gray anteriorly, becoming pale posteriorly, with pigment on cephalic papillae and at origin of dorsal fin. Peritoneum black; orobranchial cavity dark.

Largest specimen examined a 195 mm male (CAS 223482). Smallest female with yolked eggs 162 mm; smallest male with enlarged, swollen testes 124 mm.

Range Allocareproctus kallaion has been collected only in the east­central Aleutian Islands, from Seguam Pass to Yunaska Island at depths of 278–458 m ( Fig. 9 ).

Etymology

The specific epithet is derived from the Greek “ ” for “comb”, an allusion to the multiple projections on the orobuccal valve and the single row of teeth on the posterior part of the dentary.

Remarks

Unlike other species of Allocareproctus , larger specimens of A. kallaion were often collected with greatly distended stomachs filled with water. This mechanism of inflation in A. kallaion is similar to that of puffer fishes (Tetraodontiformes; Brainerd 1994, Wainwright & Turingan 1997) and frogfishes ( Antennariidae ; Pietsch & Grobecker 1987). Members of the putative sister family of the Liparidae , the Cyclopteridae , are well known for their ability to expand when disturbed, although the mechanism of inflation has not been examined ( Mecklenburg et al. 2002).

Comparisons

Allocareproctus kallaion is easily distinguished from all other species of Allocareproctus by the following characters. Its body in life is a blotchy red unlike the uniform red to peach coloration of other species. Both in life and when preserved, the anterior part of the body and orobuccal cavity are darker, unlike the pale color of other species. It differs from all other species in having multiple lobes on the orobuccal valve ( Fig. 12B ), high numbers (14–18 vs. 7–12 in all other species) of larger gill rakers with stronger spines on the tips, invariably 12 abdominal vertebrae, and a comb­like uniserial row of teeth on the dentary. Its simple teeth further distinguish it from A. tanix , A. unangas , and A. ungak , which all possess moderately to strongly trilobed teeth ( Fig. 2 ).

Several morphometric characters differ significantly between A. kallaion and all other species of Allocareproctus . Head length, body depth, snout length, suborbital depths to oral cleft and mandible, predorsal length, snout to anus length, pelvic­disk length and width, and lengths of dorsal­ and anal­fin connections to the caudal fin are less, while pelvic disk to anus length is greater than in all other species.

Figures

FIGURE 1. Species of Allocareproctus: A) A. jordani, UW 112283, 74.8 mm, male; B) A. tanix, UW 112294, holotype, 65.6 mm, male; C) A. kallaion, UW 112244, holotype, 157.0 mm, female; D) A. unangas, UW 112308, holotype, 82.5 mm, female; E) A. ungak, UW 111933, holotype, 91.0 mm, female. Scale bar = 10 mm.

FIGURE 2. Teeth of species of Allocareproctus: A) A. jordani, UW 112283, 17 mm HL; B) A. tanix, UW 113166, paratype, 17.8 mm HL; C) A. kallaion, UW 112236, paratype, 31.4 mm HL; D) A. unangas, UW 112088, paratype, 22 mm HL; E) A. ungak, UW 45239, paratype, 22 mm HL. Scale bar = 0.25 mm.

FIGURE 3. Allocareproctus kallaion, UW 112244, holotype, 157 mm, female. Head and anterior portion of body showing papillae associated with cephalic pores and exserted tips of anterior dorsal­fin rays. Illustration by B.M. Vinter.

FIGURE 6. Pectoral girdles of species of Allocareproctus: A) A. jordani, UW 112283, 74.2 mm; B) A. tanix, UW 113166, paratype, 63.8 mm; C) A. kallaion, UW 112236, paratype, 129.0 mm; D) A. unangas, UW 112088, paratype, 84.2 mm; E) A. ungak, UW 45239, paratype, 84.5 mm. Scale bar = 5 mm. c = coracoid, f = interradial fenestra, r = radial, s = scapula. Illustrations by B.M. Vinter.

FIGURE 9. Distribution of Allocareproctus kallaion based on all known material, 48 specimens in 15 lots.

FIGURE 12. Orobuccal valve of A) Allocareproctus jordani and B) Allocareproctus kallaion. Anterior to left, operculum lifted out and dorsally. Illustrations by B.M. Vinter.

FIGURE 13. Plots of principal component scores for meristic characters of species of Allocareproctus: Allocareproctus jordani (×), A. tanix (), A. kallaion(), A. unangas (), A. ungak (♢).