Revision of the snailfish genus Allocareproctus Pitruk & Fedorov (Teleostei: Liparidae), with descriptions of four new species from the Aleutian Islands
Author
Orr, James Wilder
Author
Busby, Morgan Scott
text
Zootaxa
2006
2006-04-13
1173
1
37
journal article
27066
10.5281/zenodo.2645716
6fdc6a27-0f98-454c-8f0a-4be3f202b312
1175-5326
2645716
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
).
FIGURE 9.
Distribution of
Allocareproctus kallaion
based on all known material, 48 specimens in 15 lots.
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.