See data on Catalog of Fishes here.
View data on Catalog of Fishes here.
The following is as description of the holotype and only known specimen from Gibbs et al. (1983).
Sex not determined, 87.0 mm SL. D 23. A 36. PI 3. P2 7. IP 7. PV 34. VAV 18. OV 34. VAL 20. AC 18. IA 59. IC 77. OA 54. OC 72. VAV photophores over anal–fin base 7. Branchiostegal photophores damaged. Premaxillary teeth 10 left, 9 right: from anterior to posterior, a long fixed tooth followed by a long space, a fixed fang followed by a moderate space, a short-to-long series of 1 fixed and 2 depressible teeth (middle, depressible tooth not present right) followed by a moderate space, a short fixed tooth followed by a moderate space, 2 intermediate–sized depressible teeth followed by a moderate space, and 2 short depressible teeth. Maxilla with about 10 short, slanted serra-like teeth. Mandibular teeth 15 on both sides: from anterior to posterior, a short, fixed symphysial tooth followed by a moderate space, a fixed fang followed by a long space, a long depressible tooth, a short-to-long series of 1 fixed and 3 depressible teeth (1 and 4 on right), a short-to-long series of 5 depressible teeth (1 fixed, 3 depressible right), and a short-to-long series of 3 depressible teeth. Vertebrae approximately 67 (not X-ray dense).
Measurements (in mm): Predorsal length 73.8, preanal length 64.0, prepelvic length 52.1, head length 10.9, barbel length 48.1, proximal-bulb length 1.0, distal-bulb length 1.6, distance between bulbs 1.6, fleshy orbit length ~1.8, postorbital–organ length 0.4, upper–jaw length 8.4, depth behind head 3.8, greatest depth 4.5, caudalpeduncle depth 1.5, pectoral fin damaged, pelvicfin length ~11.5, dorsal–base length 10.6, analbase length 21.6, longest premaxillary tooth 1.1, longest mandibular tooth 1.0.
Barbel stem with axis moderately darkly pigmented proximally, becoming light distally. External chevron-shaped or roundish striated areas darkly pigmented, large and closely spaced proximally, smaller and more widely spaced before bulb. Axis between bulbs unpigmented proximally, moderately dark distally. No visible pigment in filament. Proximal bulb spheroidal; distal bulb more or less ovoid, narrower distally, about 1.5 times as wide as proximal bulb.
The following is a brief desritption of the holotype from Gibbs et al. (1983).
In percent of SL: barbel length 27–81, filament length 3.9–9.4, proximal bulb 0.9–0.5, distal bulb 0.9–1.2, distance between bulbs 2.8–3.4. In percent of proximal bulb: distal bulb 140–211, distance between bulbs 420–589. In percent of distal bulb: distance between bulbs 300–279. The postorbital organ of the 1 large male is 1.7% SL, 57% of fleshy orbit. No color observations have been recorded.
Two terminal bulbs separated by a long interspace (2.8%–3.4% SL, 2.8–3.0 times distal-bulb length). Barbel long (81% SL) in the large specimen, short (27% SL) in the small specimen. Terminal filament short, 3.9%–9.4% SL, with 2 short branches together about 2 distal bulb lengths from the bulb. Distal bulb 1.4–2.1 times length of proximal bulb. Axis of stem pigmented, lightly in the small specimen, moderately darkly in the large specimen. External chevron–shaped or roundish striated areas on stem pigmented. Middorsal paired spots between occiput and dorsal-fin origin 8 (small specimen only).
Two terminal bulbs separated by a distance equal to the distal-bulb length, 1.8% SL). Barbel 55% SL. Terminal filament longer than 9.4% SL, the tip broken. Distal bulb large, 1.8% SL, 1.6 times length of proximal bulb. Axis of stem pigmented, dark proximally, light distally. External chevron-shaped or roundish striated areas on stem well pigmented. Middorsal paired spots between occiput and dorsal-fin origin 8.
Known only from the holotype, taken in the Tasman Sea off southeastern Australia.
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.
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.
Eustomias austratlanticus is a member of the subgenus Nominostomias Reagan and Trewavas (1930). The following description applies to all member of Nominostomias.
Three well-developed, free pectoral rays. Seven pelvic rays. Barbel with slender stem having little or no external pigment (axis often pigmented), no row of dark spots, and no branches proximal to the terminal bulbs (E. multifilis may have a few short filaments on the stem near the bulb). One or 2 relatively small terminal bulbs, the distalmost with a projection or filament of variable complexity (the projection almost indiscernible in a few species). No wide ventral body groove posterior to pectoral–fin base (a narrow, shallow groove observed in some specimens). Photophore and vertebral counts high. Photophores in ventral series (IC) 69–80 (seldom fewer than 72, species modes mostly 75–78), in lateral series (OC) 63–73 (seldom fewer than 66, species modes mostly 69–72), VAV and VAL 15–21 (seldom fewer than 16, species modes 17–18 and 18–19, respectively). Vertebrae in continuous series 64–71 (seldom fewer than 65, species modes mostly 67–69). No paired photophores in lateral series. Number of teeth high: premaxillary 11–20, mandibular 14–29 in large specimens (fewer in many specimens less than 100 mm SL).
Counts of fin-rays, photophores, vertebrae, and teeth are of little use in distinguishing most species of Nominostomias, for even those species that show modal differences overlap the ranges of most other species.
None of the body proportions examined by Gibbs et al. (1983) showed convincing differences among species of Nominostomias. Differences in size or relative–growth patterns appeared to characterize a number of species for which few specimens were measured, but these are believed to be artifacts of sampling. The cloud of points of species with abundant measurements usually encompassed those of species with few measurements, and in those abundant species, isometric growth is indicated for almost every body part once metamorphosis is complete. The only body measurement to indicate allometric growth is the least caudal-peduncle depth, which decreases relative to SL.
Eustomias australensis is a member of the subgenus Nominostomias Reagan and Trewavas (1930). The following description applies to all member of Nominostomias.
Three well-developed, free pectoral rays. Seven pelvic rays. Barbel with slender stem having little or no external pigment (axis often pigmented), no row of dark spots, and no branches proximal to the terminal bulbs (E. multifilis may have a few short filaments on the stem near the bulb). One or 2 relatively small terminal bulbs, the distalmost with a projection or filament of variable complexity (the projection almost indiscernible in a few species). No wide ventral body groove posterior to pectoral–fin base (a narrow, shallow groove observed in some specimens). Photophore and vertebral counts high. Photophores in ventral series (IC) 69–80 (seldom fewer than 72, species modes mostly 75–78), in lateral series (OC) 63–73 (seldom fewer than 66, species modes mostly 69–72), VAV and VAL 15–21 (seldom fewer than 16, species modes 17–18 and 18–19, respectively). Vertebrae in continuous series 64–71 (seldom fewer than 65, species modes mostly 67–69). No paired photophores in lateral series. Number of teeth high: premaxillary 11–20, mandibular 14–29 in large specimens (fewer in many specimens less than 100 mm SL).
Counts of fin-rays, photophores, vertebrae, and teeth are of little use in distinguishing most species of Nominostomias, for even those species that show modal differences overlap the ranges of most other species.
None of the body proportions examined by Gibbs et al. (1983) showed convincing differences among species of Nominostomias. Differences in size or relative–growth patterns appeared to characterize a number of species for which few specimens were measured, but these are believed to be artifacts of sampling. The cloud of points of species with abundant measurements usually encompassed those of species with few measurements, and in those abundant species, isometric growth is indicated for almost every body part once metamorphosis is complete. The only body measurement to indicate allometric growth is the least caudal-peduncle depth, which decreases relative to SL.
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.
Regan CT, Trewavas E. 1930. The fishes of the families Stomiatidae and Malacosteidae. Danish Dana Expedition 1920−22 6:1−143.
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.
Regan CT, Trewavas E. 1930. The fishes of the families Stomiatidae and Malacosteidae. Danish Dana Expedition 1920−22 6:1−143.
The only known specimen, the holotype, is 88 mm SL.
Tasman Sea, off southeastern Australia, 36°37'S, 152°10'E, depth 0-500 meters.
Southeastern Atlantic, 27°14'S, 2°56'E, depth 0-2000 meters.
Holotype: AMS I.20901-001.
Holotype: ISH 1554-1971.
