Eustomias grandibulbus Gibbs, Clarke & Gomon 1983

See data on Catalog of Fishes here.

The following is a description of the holotype, the only known specimen, from Gibbs et al. (1983). Female, 161.0 mm SL. D 26. A 40. PI 3. P2 7. IP 7. PV 31. VAV 18. OV 32. VAL 20. AC 18. IA 56. IC 74. OA 52. OC 70. VAV photophores over anal–fin base 7. Branchiostegal photophores 11.

Premaxillary teeth 15 left and right: from anterior to posterior, a long fixed tooth followed by a wide space, a fixed fang followed by a wide space, a short-to-long series of 1 fixed and 2 depressible teeth (all depressible right), a short-to-long series of 1 fixed and 3 depressible teeth, a snort–to–long series of 3 depressible teeth, 3 short depressible teeth. Maxilla with about 3 short erect teeth and 19 slanted, serra-like teeth. Left mandible damaged. Right mandibular teeth 19: from anterior to posterior, broken symphysial tooth followed by a moderate space, a fixed fang followed by a wide space, a long depressible tooth, 2 short depressible teeth, a long depressible tooth, a short-to-long series of 2 fixed and 2 depressible teeth, a short-to-long series of 5 depressible teeth, 2 short to long series of 4 depressible teeth, 2 short depressible teeth. Vertebrae 67.

Axis of barbel stem densely peppered with melanophores up to proximal bulb; a few melanophores on axis between bulbs; axis of terminal filament moderately darkly pigmented until about base of 3rd branch, becoming lighter distally. External chevron–shaped or roundish striated areas of stem unpigmented. Proximal bulb spheroidal; distal bulb ovoid, somewhat smaller anteriorly. Distance between bulbs short, less than length of distal bulb. Terminal filament almost 20% SL, with 5 well-separated, long side branches, the 1st arising about 1 distal-bulb length from bulb, the 5th at about half filament length; each branch and main filament bearing 1 or more short side branches. Small bulblets present in all filament branches, most much smaller than filament diameter and none causing external swellings. No color observations recorded.

Two terminal bulbs separated by a short interspace (1.3% SL, shorter than length of distal bulb in only known specimen). Barbel 68% SL. Terminal filament long (20% SL), with a series of 5 long branches beginning a short distance (1 distal-bulb length) from bulb, all with small bulblets, none of which approaches the diameter of the filament. All long branches with 1 or more short branches. Stem axis uniformly peppered with melanophores; lightly pigmented on axis between bulbs and in proximal part of filament. Number of middorsal spots under skin uncertain (obscure and diffuse in holotype).

The only known specimen was taken in the southeastern Atlantic not far off South Africa.

Gibbs RH, Jr, Clarke TA, Gomon JR. 1983. Taxonomy and distribution of the stomioid fish genus Eustomias (Melanostomiidae), I: Subgenus Nominostomias. Smithsonian Contributions to Zoology 380:1–139.

The holotype is 161 mm SL.

Southeastern Atlantic, 34°25'S, 14°47'E, depth 0-112 meters.

Holotype: ISH 1272-1971.

Two terminal bulbs separated by a short interspace, shorter than length of distal bulb. Barbel 68% SL. Terminal filament long (20%), with a series of 5 long branches beginning a short distance (a distal bulb length) from bulb, all with small bulblets, none of which approaches the diameter of the filament. All branches with 1 or more short branches. Stem axis peppered with melanophores; lightly pigmented on axis between bulbs and in proximal part of filament. Number of middorsal paired spots under skin uncertain (obscure and diffuse in holotype) (Ref. 11333).

Dorsal spines (total): 0; Dorsal soft rays (total): 26; Analspines: 0; Analsoft rays: 40; Vertebrae: 67

Known based on a single specimen taken at a depth between 0-112 m.

Eustomias grandibulbus

DIAGNOSIS.—Two terminal bulbs separated by a short interspace (1.3% SL, shorter than length of distal bulb in only known specimen). Barbel 68% SL. Terminal filament long (20% SL), with a series of 5 long branches beginning a short distance (1 distal-bulb length) from bulb, all with small bulblets, none of which approaches the diameter of the filament. All long branches with 1 or more short branches. Stem axis uniformly peppered with melanophores; lightly pigmented on axis between bulbs and in proximal part of filament. Number of middorsal spots under skin uncertain (obscure and diffuse in holotype).

DESCRIPTION OF HOLOTYPE (only known specimen).—Female, 161.0 mm SL. D 26. A 40. P1 3. P2 7. IP 7. PV 31. VAV 18. OV 32. VAL 20. AC 18. IA 56. IC 74. OA 52. OC 70. VAV photophores over anal-fin base 7. Branchiostegal photophores 11. Premaxillary teeth 15 left and right: from anterior to posterior, a long fixed tooth followed by a wide space, a fixed fang followed by a wide space, a short-to-long series of 1 fixed and 2 depressible teeth (all depressible right), a short-to-long series of 1 fixed and 3 depressible teeth, a short-to-long series of 3 depressible teeth, 3 short depressible teeth. Maxilla with about 3 short erect teeth and 19 slanted, serra-like teeth. Left mandible damaged. Right mandibular teeth 19: from anterior to posterior, broken symphysial tooth followed by a moderate space, a fixed fang followed by a wide space, a long depressible tooth, 2 short depressible teeth, a long depressible tooth, a short-to-long series of 2 fixed and 2 depressible teeth, a short-to-long series of 5 depressible teeth, 2 short to long series of 4 depressible teeth, 2 short depressible teeth. Vertebrae 67.

Measurements (in mm): Predorsal length 136.5, preanal length 118.0, prepelvic length 88.7, head length 18.3, barbel length 109.3, proximal-bulb length 1.8, distal-bulb length 2.6, distance between bulbs 2.1, filament length 31.7, snout length 6.6, fleshy orbit length 4.7, postorbital-organ length 1.0, upper-jaw length 15.6, lower-jaw length 17.2, depth behind head (greatest depth) 11.7, caudal-peduncle least depth 2.2, pectoral-fin length 20.3, pelvic-fin length 22.2, dorsal-fin base 22.0, anal-fin base 42.8, longest premaxillary tooth 2.8, longest mandibular tooth 1.7.

Axis of barbel stem densely peppered with melanophores up to proximal bulb; a few melanophores on axis between bulbs; axis of terminal filament moderately darkly pigmented until about base of 3rd branch, becoming lighter distally. External chevron-shaped or roundish striated areas of stem unpigmented.

Proximal bulb spheroidal; distal bulb ovoid, somewhat smaller anteriorly. Distance between bulbs short, less than length of distal bulb. Terminal filament almost 20% SL, with 5 well-separated, long side branches, the 1st arising about 1 distal-bulb length from bulb, the 5th at about half filament length; each branch and main filament bearing 1 or more short side branches. Small bulblets present in all filament branches, most much smaller than filament diameter and none causing external swellings.

No color observations recorded.

SIMILAR SPECIES.—In E. crossotus, the long branches of the terminal filament all arise close together near the distal bulb, these branches lack any short side branches, and the distance between bulbs is shorter (0.4%–0.8% SL. in large specimens vs. 1.6% in grandibulbus). In the only other species with a similar filament, E. arborifer, the filament is shorter (9% SL or less) and has much larger bulblets, many of which approach the diameter of the filament and often cause external swellings. In the absence of small specimens of grandibulbus, possible resemblance to small bimargaritatus cannot be ascertained.

DISTRIBUTION.—The only known specimen was taken in the southeastern Atlantic not far off South Africa (Figure 44).

ETYMOLOGY.—A Latin noun in apposition, grandibulbus is a combination of grandis (large) plus bulbus (a swelling), referring to the large distal bulb of this species.

MATERIAL EXAMINED (1 female).—Holotype: ISH 1272/71 (, 161.0), 34°25′S, 14°47′E, 0–112 m, 2108–2155, 28 Mar 1971.