Description
(
англиски
)
добавил Deep sea Fishes of the World LifeDesk
Barbel length apparently increases from 31%–32% SL at 66–79 mm to 52%–63% in specimens 82 mm and larger. There is no barbel pigment in the smallest specimen; all others have the stem axis well pigmented, either peppered with melanophores or having streaky and diffuse pigment or both. On the axis between bulbs and in the filament, pigmentation is lighter or absent, without apparent relation to SL. The external chevron–shaped or roundish striated areas are unpigmented.
The proximal bulb varies from almost spherical to an elongate ovoid about twice as long as wide. In specimens 66–82 mm SL this bulb is 0.8%–1.0% SL, increasing relatively to 1.0%–1.3% at 123–154 mm.
The distal bulb is variously an oblate spheroid, pear–shaped with a narrow distal end, ovoid, or an elongate ovoid about twice as long as wide. In the smallest specimen (66 mm) it is 0.9% SL; in the others, 79–154 mm, it is 1.3%–1.7% SL. The distal bulb is longer than the proximal in all specimens and increases from 1.1 times proximalbulb length in the smallest specimen to 1.8 times its length in the largest.
The distance between bulbs apparently does not change with growth, decreasing relative to SL from 0.6%–1.4% at 66–82 mm to 0.4%–0.8% at 123–154 mm. Only in the smallest specimen is the distance longer (1.5:1) than the distal bulb; in the largest it is less than one-third the length of the distal bulb.
The single terminal filament has 2–4 long side branches arising a short distance (slightly less to slightly more than 1 distal-bulb length) from the bulb. Neither the main filament nor its long branches have any more side branches. Many very small bulblets, mostly along the axis, are present in the specimens 82–154 mm; bulblets were not discerned in the 66 and 79 mm ones. The bulblets are much smaller than the filament diameter.
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- Kenaley, Christopher
- автор
- Kenaley, Christopher
Comprehensive Description
(
англиски
)
добавил Smithsonian Contributions to Zoology
Eustomias crossotus
Eustomias bibulbosus.—Parin and Pokhilskaya, 1974:353–355 [part; Vityaz stas 6064, 6493; fig. 19a; specimens examined by us].—Parin et al., 1977:101, 102 [part; Vityaz stas 7187, 7192; specimens examined by us].
DIAGNOSIS.—Two terminal bulbs separated by a short interspace (0.4%–1.5% SL, 0.3–1.5 times length of distal bulb). Barbel 52%–63% SL in specimens larger than 80 mm. Terminal filament long (11%–22% SL, except in smallest specimen), with 2–4 long branches arising closely together a short distance (less than 0.5 to about 1.3 distal-bulb lengths) from distal bulb. All branches with very small bulblets and without sub-branches. Stem axis well pigmented except in smallest specimen (66 mm); stem between bulbs and proximal part of filament usually lightly pigmented. Middorsal paired spots under skin between occiput and dorsal-fin origin usually 8, sometimes 7.
DESCRIPTION.—Barbel length apparently increases from 31%–32% SL at 66–79 mm to 52%–63% in specimens 82 mm and larger. There is no barbel pigment in the smallest specimen; all others have the stem axis well pigmented, either peppered with melanophores or having streaky and diffuse pigment or both. On the axis between bulbs and in the filament, pigmentation is lighter or absent, without apparent relation to SL. The external chevron-shaped or roundish striated areas are unpigmented.
The proximal bulb varies from almost spherical to an elongate ovoid about twice as long as wide. In specimens 66–82 mm SL this bulb is 0.8%–1.0% SL, increasing relatively to 1.0%–1.3% at 123–154 mm.
The distal bulb is variously an oblate spheroid, pear-shaped with a narrow distal end, ovoid, or an elongate ovoid about twice as long as wide. In the smallest specimen (66 mm) it is 0.9% SL; in the others, 79–154 mm, it is 1.3%–1.7% SL. The distal bulb is longer than the proximal in all specimens and increases from 1.1 times proximal-bulb length in the smallest specimen to 1.8 times its length in the largest.
The distance between bulbs apparently does not change with growth, decreasing relative to SL from 0.6%–1.4% at 66–82 mm to 0.4%–0.8% at 123–154 mm. Only in the smallest specimen is the distance longer (1.5:1) than the distal bulb; in the largest it is less than one-third the length of the distal bulb.
The single terminal filament has 2–4 long side branches arising a short distance (slightly less to slightly more than 1 distal-bulb length) from the bulb. Neither the main filament nor its long branches have any more side branches. Many very small bulblets, mostly along the axis, are present in the specimens 82–154 mm; bulblets were not discerned in the 66 and 79 mm ones. The bulblets are much smaller than the filament diameter.
The filament is only 3% SL in the smallest (66 mm) specimen. Rapid growth occurs after this, and the filament is 11%–22% after 82 mm; the relatively shortest filament is that of the largest specimen, suggesting a decrease in relative length with growth in SL. In the smallest specimen, the filament is 3.3 times as long as the distal bulb; in the others it is 8.5–14.0 times the bulb length.
The postorbital organ of the only large male (128 mm) is 1.6% SL, 49% of fleshy orbit length.
No observations of barbel colors have been recorded.
DESCRIPTION OF HOLOTYPE.—Male, 128.1 mm SL. D 25. A 38. P1 3. P2 7. IP 8. PV 30. VAV 20. OV 31. VAL 21. AC 18. IA 58. IC 78. OA 52. OC 72. VAV photophores over anal-fin base 8. Branchiostegal photophores 11. Premaxillae missing. Maxilla with a short erect tooth and about 20 very short, slanted, closely-spaced serra-like teeth. Mandibular teeth 16 left, 15 right: from anterior to posterior, a short fixed symphysial tooth followed by a long space, a fixed fang (a replacement fang inside and posterior) followed by a long space, 2 short fixed teeth (the 1st shorter than the 2nd, missing on right), a long and a short depressible tooth, 3 increasingly longer depressible teeth, another short-to-long series of 4 depressible teeth (smaller than those of the preceding series), and 3 short depressible teeth. Vertebrae 68 (the first only partially ossified).
Measurements (in mm): Predorsal length 105.0, preanal length 88.0, prepelvic length 68.0, head length 15.0, barbel length 68.6, proximal-bulb length 1.4, distal-bulb length 2.0, distance between bulbs 1.0, filament length 22.1, fleshy orbit length 4.1, postorbital-organ length 2.0, upper jaw lacking premaxillae, lower-jaw length 14.0, depth behind head (greatest depth) 8.5, caudal-peduncle least depth 1.9, pectoral-fin length 14.5, pelvic-fin length 17.0, dorsal-base length 15.8, anal-base length 31.7, premaxillary teeth missing, longest mandibular tooth 1.5.
Barbel with longish oblate-spheroidal proximal bulb with almost flat ends, oblate-spheroidal distal bulb with asymmetrically narrowed anterior end. Terminal filament with 4 long branches, the 1st arising about length of distal bulb beyond bulb.
SIMILAR SPECIES.—In the only specimen of grandibulbus (161 mm), which is larger than the largest crossotus (154 mm), the long branches of the filament arise farther apart from one another than in crossotus, some up to halfway along the filament, and have short side branches, which crossotus lacks; the distance between the bulbs is 1.6% SL (0.4%–0.8% in the largest crossotus). Eustomias arborifer has a shorter terminal filament with much larger bulblets (often forming swellings) and lacks dark pigment in the barbel of specimens up to 150 mm SL; its males have a smaller postorbital organ (maximum 1.1% SL, 38.1% of fleshy orbit vs. 1.6% and 48.8% in crossotus). Small bimargaritatus with only 2 filament branches and these branches very close to the distal bulb have no obvious barbel characters that differentiate them from small crossotus, but the 2 species are widely separated geographically.
DISTRIBUTION.—Eastern Indian Ocean off Sumatra; South China Sea and northwestern Pacific between 10° and 20°N and 120° and 140°E; southwestern Pacific off the Solomon Islands (Figure 41).
ETYMOLOGY.—An adjective derived from the Greek krossotos (fringed), referring to the branched filament of this species.
MATERIAL EXAMINED (1 male, 3 females, 2 unsexed).—Holotype: ZMUC P202846 (, 128.1), 16°55′N, 120°03′E, 0–∼300 m (600 mw), 2245, 15 Jun 1929.
Paratypes: ZMUC P202850 (?, 65.5), 03°36′S, 97°37′E, 0–∼150 m (300 mw), 2210, 10 Sep 1929. IOAN uncat. (?, 79 mm), 13°31′N, 139°58′E, 0–330 m, 5 Jul 1971. IOAN uncat. (, 82.3), 09°45′S, 164°09′E, 0–70 m, 7 Feb 1969. IOAN uncat. (, 153.7), 17°53′N, 127°56′E, 0–200 m, 11 Feb 1975. USNM 223965 (, 122.9), 15°21′N, 126°54′E, 0–200 m, 13 Feb 1975.
Eustomias bimargaritatus Regan and Trewavas, 1930
Eustomias bimargaritatus Regan and Trewavas, 1930:84, 85 [7 syntypes; barbels fig. 63].
Eustomias bibulbosus.—Beebe and Crane, 1939:211 [no additional specimens; bimargaritatus in synonymy].—Morrow and Gibbs, 1964:396 [Beebe and Crane's decision accepted; 149.6 mm specimen may be bimargaritatus, see “Remarks” below].—Blache et al., 1970:171 [part; fig. 459c,d only].—Bekker et al., 1975 [part; stas 1253, 1255; examined by us].
DIAGNOSIS.—Two terminal bulbs separated by a short interspace (0.6%–1.6% SL, 0.6–1.7 times length of distal bulb). Barbel length 58%–70% SL in specimens larger than 90 mm. Terminal filament 10%–23% SL, except in some small specimens, with 2–3 (usually 2) prominent branches arising closely together at 1–5 distal-bulb lengths from the distal bulb in specimens to 114 mm SL (at 10 bulb lengths in a 200 mm specimen). Stem of filament proximal to major branches with widely-spaced tiny bulblets and without short basal branches; all long branches with very small, well-spaced bulblets (bulblets larger and more conspicuous in a 200 mm specimen). Barbel without melanophores (rarely very sparse pigment on axis of stem or filament). Paired middorsal spots between occiput and dorsal-fin origin probably 8, often diffuse or obscure.
DESCRIPTION.—Rapid increase in barbel length is indicated by specimens 71–74 mm SL with barbels 34%–60% SL. All specimens 89 mm or larger have barbels 58%–70% SL. The barbel is entirely without black pigment in all except 2 specimens, and in those the pigment is difficult to discern. In 1, there are 2 short areas of stem where melanophores form a row along the axis, and there is a row of very tiny flecks along the axis of the filament stem. The other has only a short pigment streak at the base of the filament. External chevron-shaped or roundish striated areas are unpigmented.
The proximal bulb may be spherical or an oblate spheroid. It is 0.7%–1.3% SL at all sizes.
The distal bulb is variously an oblate spheroid or short oval to an elongate, straight-sided oval; 2 specimens have a small, distinct proximal projection directed proximad. The bulb is 1.0%–1.8% SL and 1.0–1.8 times the length of the proximal bulb at all sizes.
The distance between bulbs is 0.6%–1.6% SL, not changing obviously with growth in SL, and is 0.4–1.3 times the length of the distal bulb.
The terminal filament has 2 branches arising together a moderate distance (1–5 distal-bulb lengths) from the distal bulb (10 bulb lengths in the 200 mm specimen). Regan and Trewavas (1930) record 2–4 branches (including the main filament); we observed no variants from 3 (2 branches). Small side branches on the filament proximal to the main branches are absent, except in a 117 mm specimen, which has 1. The main filament is thicker than the 2 long branches and has more secondary branches and more and larger bulblets. Except in the 200 mm specimen, bulblets are tiny and quite widely spaced in the branches, and proximal to the branches they are so tiny and widely spaced that they are difficult to discern. In the 200 mm specimen bulblets in the branches are prominent and closely spaced, causing swellings in the smallest secondary branches.
Rapid filament growth is indicated by specimens 71–74 mm SL with filaments 5%–17% SL. Between 85 and 117 mm, filaments are 10%–16% SL, with no apparent change relative to SL, but the 200 mm specimen has a filament 23% SL. The filament is 5.4–11.2 times the distal-bulb length in specimens up to 117 mm SL, 16.9 times the bulb length in the 200 mm specimen.
The only large male (143 mm) has a postorbital organ 1.3% SL, 49% of fleshy orbit length (barbel observed at sea, but lost prior to measurement). The next largest male, 114 mm, has a small organ, 0.6% SL.
Bulbs of 10 freshly caught specimens 68.0–142.8 mm all were pale green, with variation subjectively noted as yellow-green, lime-green, or grass-green. No other barbel pigments were noted. Postorbital organs were white in most, but red in 1 female and reddish on 1 side, white on the other of 1 male.
SIMILAR SPECIES.—In bimargaritoides, the most similar species, the 3 branches of the filament arise much farther distad, 6–11 distal-bulb lengths from the distal bulb (branching occurs at 10 bulb lengths in the 200 mm specimen of bimargaritatus, the only one in which it occurs at more than 5 bulb lengths), bulblets in the branches are closer together and somewhat larger, there are no bulblets in the filament proximal to the branches, and there are 1–6 small side branches in the proximal half of the filament (1 bimargaritatus has a single such branch). Also in bimargaritoides, the filament is longer (21%–28% SL vs. 17% or less except in the 200 mm specimen), the barbel length tends to be shorter in specimens larger than 80 mm (44%–59% vs. 51%–67%). Eustomias arborifer has a shorter terminal filament (9% SL or less) with its first branching always close to the distal bulb and with much larger bulblets; large males (126–150 mm) have a smaller postorbital organ (0.7%–1.0% SL) than does the only large male (143 mm) bimargaritatus (1.3% SL). Small crossotus, perhaps also grandibulbus, before stem pigment has developed, would be virtually impossible to differentiate from small bimargaritatus in which the branches of the filament arise close to the distal bulb; fortunately, these species are well separated geographically.
DISTRIBUTION.—Across the North Atlantic between 18° and 28°N from the Florida Current to north of the Cape Verde Islands (Figure 41).
- библиографски навод
- Gibbs, Robert H., Jr., Clarke, Thomas A., and Gomon, Janet R. 1983. "Taxonomy and distribution of the stomioid fish genus Eustomias (Melanostomiidae), I: subgenus Nominostomias." Smithsonian Contributions to Zoology. 1-139. https://doi.org/10.5479/si.00810282.380
