Gadomus longifilis (Goode & Bean, 1885)

Bañón, Rafael, Arronte, Juan Carlos, Barros-García, David, Vázquez-Dorado, Sandra & Carlos, Alejandro De, 2013, Taxonomic study of Bathygadidae fishes (Gadiformes) from Atlantic Spanish waters combining morphological and molecular approaches, Zootaxa 3746 (4), pp. 552-566 : 558-560

Gadomus longifilis (Goode & Bean, 1885)

Fig. 3 .

Bathygadus longifilis Goode & Bean, 1885: 599 . Albatross station 2392, 28°47'30"N, 87°27'00"W, 1,324 m. depth. Syntypes:?SU 9546 (1), USNM 37338 (2). Type catalog: Böhlke 1953:56. Parr, 1946: 8–17 (description, key); Iwamoto, 1970: 327– 352 (description, key); Marshall & Iwamoto, 1973: 518–530 (description, key); Howes & Crimmen, 1990: 192–201 (description, key).

Material examined. MHNUSC 25005- 1, 278 mm TL, 6th August 2011, Galicia Bank; 42º 40.390’N— 11º 31.670’W; 1,450 m depth; MHNUSC 25005- 2, 291 mm TL, 6th August 2011, Galicia Bank; 42º 40.390’N— 11º 31.670’W; 1,450 m depth; MHNUSC 25005- 3, 295 mm TL, 7th August 2011, Galicia Bank; 42º 58.51’N— 11º 59.23’W; 1,683 m depth.

Description. Body elongated and attenuated to the caudal peduncle; head small, 6.7–7.7 times in total length; snout blunt, 3.7–4.4 times into head; interorbital width about equal to horizontal diameter of orbit; long chin barbel present, strongly developed and 1.9–2.4 in head length; dorsal, pectoral and ventral fins with a single elongated ray, elongated second dorsal ray 1.8–2.4, elongated second pectoral ray 2.0–2.3 and elongated first pelvic ray 2.0– 2.2 in the head length. The main morphometric and meristic characteristics are presented in Table 4 .

Habitat and distribution. Benthopelagic in tropical and subtropical North Atlantic between 520 and 2,165 m depth (Geistdoerfer, 1990). Amphi-Atlantic distribution; in western Atlantic it occurs in West Greenland (a single specimen), off east coast of Florida, Straits of Florida, Gulf of Mexico and Caribbean sea and in eastern Atlantic from the northwest of Spain (Galicia), Portugal, Azores, Canary Islands, Morocco, Mauritania and Gulf of Guinea ( Marshall & Iwamoto, 1973; Maul, 1976; Geistdoefer, 1990; Jørgensen, 1996; Bañón et al. 2010; Sobrino et al. 2012).

Gadomus arcuatus (Goode & Bean, 1886) Fig. 4 .

Bathygadus arcuatus Goode & Bean, 1886: 158 . Off Martinique Island, West Indies, Blake station 205, 611 m. depth. Holotype: MCZ 28007. Parr, 1946: 8–17 (description, key); Marshall & Iwamoto, 1973: 518–530 (description, key); Howes & Crimmen 1990: 192–201 (description, key).

Material examined. MHNUSC 25006- 1, 566 mm TL, 13th May 2011, Avilés Canyon; 43º 57.850’N— 6º 28.050’W; 1,450 m depth.

Description. Body elongated and attenuated to the caudal peduncle; upper profile to first dorsal fin strongly inclined, with a pronounced hump-backed appearance; head moderately large, 6.2 times in total length; snout 4.8 times into head; interorbital width about equal to horizontal eye diameter and 5.4 times into head length; chin barbel present and of moderate size, 0.7 in head length; mouth large and terminal jaws beyond the posterior margin of the orbit; only one pelvic ray elongated but broken is patent, all rest of elongated rays are presumably broken, elongated first pelvic rays 1.3 and elongated first pectoral rays 1.3 in the head length. The main morphometric and meristic characteristics are presented in Table 5 .

Habitat and Distribution. Benthopelagic in tropical and subtropical Atlantic at depths between 610 and 1,631 m (Iwamoto, 1990; Sobrino et al. 2012). Amphi-Atlantic distribution; in western Atlantic from Nova Scotia ( Canada), Gulf of Mexico, Caribbean, Surinam, French Guyana, north-eastern coast of South America and Brazil and in eastern Atlantic from Morocco, Azores, Canary Islands, Mauritania, Guinea-Bissau and Gabon ( Marshall & Iwamoto, 1973; Iwamoto, 1990; Geistdoerfer, 1990; Howes & Crimmen, 1990; Melo & Menezes, 2002; Melo et al. 2010; Halliday et al. 2012; Sobrino et al. 2012).

Figures

FIGURE 3. Gadomus longifilis from the north-east Atlantic Ocean, MHNUSC 25005 – 3, 295 mm total length.

FIGURE 4. Gadomus arcuatus from the north-east Atlantic Ocean, MHNUSC 25006 – 1, 566 mm total length.

Tables

TABLE 4. Comparison of morphometric, meristic data and respective body proportions for specimens of Gadomus longifilis.

Gadomus longifilis MHNUSC 25005 (1–3)	Parr (1946)	Iwamoto (1970) N=53	Marshall & Iwamoto Howes & Crimmen (1973) (1990) N=29 N=15
Total Length (mm) 278–296	—	117–290	— —
Head length (mm) 38–41	—	19–45	25–46 —
As % TL
Head length 13.1–14.9	15–18	—	~15 —
As % HL
Eye diameter 17.1–22.7	21–23	24–28	23.1–28.0 23.5–27.7
Preorbital length 22.7–26.8	28–30	26–31	26.3–28.9 —
Postorbital length 54.5–57.9	—	46–53	— —
Interorbital length 21.1–22.7	23–25	21–28	21.1–25.0 19.7–24.8
Upper jaw length 56.1–60.5	60	57–65	52.6–60.0 —
Barbel length 40.9–51.2	40–45	13–48	31.6–40.0 40.0–50.0
1st Predorsal length 112.2–113.6	—	—	105.3–116.0 —
2nd Predorsal length 152.6–156.8	—	—	135.1–146.1 —
1st Dorsal base length 34.2–39.0	30	—	— —
Preanal length 197.6–202.6	—	—	171.1–182.8 —
Length of longest ray of first 175.0–243.9 dorsal	200	190	— —
Pectoral length 204.5–234.1	180	200	— —
Ventral length 204.5–217.1	160–170	250	— —
Body depth 87.8–94.7	—	—	65.8–77.1 —
Meristic features
1st Dorsal fin rays II+9–10	—	II+8–10	9–11 II+9–10
Ventral fin rays 8	8	8	8 8
Pectoral fin rays 16–17	14–16	14–18	14–16 13–16
Gill rakers 7+29–31	—	7–8+26–31	5–7+1+27–29 6–8+27–29
Pyloric caeca 9–12	10–12	9–13	— 5–12

TABLE 5. Comparison of morphometric, meristic data and respective body proportions for specimens of Gadomus arcuatus.

Gadomus arcuatus Total Length (mm)	MHNUSC Parr, 1946 (25005-1) 566 —	Marshall & Iwamoto Howes & Crimmen (1973) N=15 (1990) N=10 — —
Head length (mm) As % TL Head length	91 — 16.1 19–22	43–101 — ~20 —
As % HL Eye diameter Preorbital length	18.7 17–20 20.9 25–30	17.8–26.7 20.6–27.0 28.0–30.3 —
Postorbital length Interorbital length Upper jaw length	60.4 — 18.7 15–16 52.7 55	— — 16.7–20.0 17.0–21.8 52.0–57.3 —
Barbel length 1st Predorsal length 2nd Predorsal length	72.5 60–65 118.7 — 160.4 —	65.6–87.3 67.1–94.8 117.4–125.4 — 150.0–160.4 —
1st Dorsal base length Preanal length	41.8 — 214.3 —	— — 172.7–192.0 —
Pectoral length Ventral length	128.6 80 128.6 125–130	— — — —
Body depth Meristic features 1st Dorsal fin rays Ventral fin rays Pectoral fin rays	113.2 — II+10 12 8 8 25 21–25	80–90 — 11–13 II+10–11 8 8 22–25 20–22
Gill rakers Pyloric caeca	5+21 [phone]	4–6+18–21 4–5+19–23 — 25–30