A new, dwarf species of Grammonus (Teleostei: Bythitidae) found off Vietnam

A new species of the viviparous fish genus Grammonus (Ophidiiformes: Bythitidae) is described, based on two ripe males, 32–55 mm SL. They were caught over a muddy bottom in a shrimp trawl at 70–119 m off Central Vietnam. A comparison with the nine hitherto described Grammonus species shows them to be clearly distinct from other species. Except for G. ater, G. minutus differs from all other species by having either more or fewer dorsal (75–76) and anal (54–55) fin rays. It differs from G. ater i.a. by having more pectoral fin rays (22–23 vs. 18–19).     

Ecomorphological dimorphism of juvenile <Emphasis Type="Italic">Trachurus japonicus</Emphasis> in Wakasa Bay,Japan

Morphometric analyses of marine pelagic fishes have generally been conducted for stock identification rather than for ecomorphological understanding. Many papers on stock identification of Trachurus japonicus reported polymorphisms in the Japanese Islands waters. However, none of them has found polymorphism in fish less than 100 mm standard length (SL), despite the environmental differences experienced by juvenile cohorts. The objective of this study was to detect ecomorphological polymorphism of juvenile T. japonicus (<100 mm SL) in Wakasa Bay, Japan, where multiple juvenile cohorts appear. From analyses of size frequency distributions and otolith microstructure, five cohorts were recognized in the bay from September 2003 to August 2004. We then compared 17 morphometric characters on body, fin, and otolith morphology, and found cohort-specific and roughly dimorphic pattern (a streamlined morph and a compressed morph). The dimorphism was markedly observed in 50–70 mm SL, and was regarded as specific to the juvenile stage by comparison with the senior dimorphisms (≥100 mm SL). Referring to the literatures on functional morphology, the streamlined morph and the compressed morph were considered to be suitable to body and caudal fin (BCF) periodic propulsion and BCF transient propulsion, respectively. The juvenile dimorphism was interpreted as adaptive in its developmental environments (i.e., ecomorphological dimorphism) by relating the functional differences to the inferred ecological differences: the streamlined morph is adaptive to feed on larval Engraulis japonicus in coastal waters, whereas the compressed morph is adaptive to associate with jellyfishes in offshore waters.     

Larval and juvenile development of <Emphasis Type="Italic">Lestidiops sphyraenopsis</Emphasis> Hubbs, 1916 (Aulopiformes: Paralepididae) in the western North Pacific,with a reexamination of the holotype of <Emphasis Type="Italic">Stemonosudis molesta</Emphasis> (Marshall, 1955)

The early life stages of Lestidiops sphyraenopsis (Paralepididae) are described on the basis of 14 specimens [7.8 mm in notochord length (NL)–88.6 mm in standard length (SL)] collected from the western North Pacific, and the holotype of Stemonosudis molesta is reexamined. Larval L. sphyraenopsis occurred in the Kuroshio waters, and juveniles were taken in the Kuroshio–Oyashio transition waters. Diagnostic characters of larval and juvenile L. sphyraenopsis are 96–101 myomeres; 27–31 anal fin rays; 4–9 peritoneal pigment sections in larvae (7.8 mm NL–27.3 mm SL); dorsal and anal pigment patches present; and anus located anterior to a vertical through dorsal fin origin. Stemonosudis molesta, known only from the holotype from the South Pacific, is similar to immature specimens of L. sphyraenopsis, but can be clearly distinguished from the latter by having higher vertebral counts (105 vs. 96–101) and by morphometric and pigment differences. Consequently, S. molesta is a valid species, and the distribution of L. sphyraenopsis is restricted to the North Pacific.     

Liopropoma dorsoluteum sp. nov., a new serranid fish from Okinawa, Japan

A new serranid fish,Liopropoma dorsoluteum sp. nov., is described on the basis of two specimens from Yaeyama Is., Okinawa, Japan. The new species is most similar toL. erythaeum Randall & Taylor, 1988, in having the following characters: Dorsal fin rays VIII, 12; anal fin rays III, 9; pored lateral line scales 52–53; anterior nostril situated midway between posterior nostril and anterior tip of snout; slightly forked caudal fin with both lobes rounded. It differs from the latter species in having a shorter pectoral fin (23.4–23.8% SL vs. 26.9–29.0% SL), greater preanus length (65.6–68.0% SL vs. 63.3–65.1% SL), fewer gill rakers (6+12 vs. 6–7+14–15) and yellow coloration on the back (vs. light red on head and body) in fresh specimens.     

A new species of deepwater cardinalfish, <Emphasis Type="Italic">Epigonus mayeri</Emphasis>, from the eastern Central Atlantic,and redescription of <Emphasis Type="Italic">Epigonus heracleus</Emphasis> Parin and Abramov 1986 (Perciformes: Epigonidae)

A new epigonid fish, Epigonus mayeri, is described on the basis of two specimens (109.7–113.8 mm in standard length: SL) from off Angola, and Epigonus heracleus Parin and Abramov 1986 is redescribed on the basis of 12 additional specimens with type specimens from off eastern New Zealand. These species belong to a subgroup of Epigonus, known as the “Epigonus robustus group,” which have a pungent opercular spine and VII-I, 9 dorsal-fin rays. The new species differs from other species of the group by having a sharp-pointed mustache-like process, presence of a rib on the last abdominal vertebra, vertebrae 10 + 15, tongue toothless, pyloric caeca 5, pectoral fin reaching to vertical line from anus (length 22.2–23.6% SL), orbital diameter 16.4–17.0% SL, head length 37.8–38.0% SL, and lower jaw length 16.7–17.0% SL.     

Juvenile morphology and occurrence patterns of three Butis species (Gobioidei: Eleotridae) in a mangrove estuary, southern Thailand

Juveniles of three eleotrid Butis species (B. butis, B. humeralis, and B. koilomatodon) are described; their occurrence patterns were examined in Sikao Creek, a mangrove estuary located in southern Thailand. Juveniles of each species were distinguished by the following characters: B. butis with no bands on body and pale pelvic fins; B. humeralis with no bands on body and densely pigmented pelvic fins; and B. koilomatodon with 5–6 regular bands on body and a fleshy process (preorbital knob) on the snout. Although B. butis shared the aforementioned characters with B. amboinensis found in the same estuary, the former was distinguished from the latter by having a greater number of pectoral fin rays (18–21 vs. 17) and a deeper caudal peduncle. Distribution patterns of the three Butis species in Sikao Creek were distinguishable from each other. Smaller B. butis [mean ± SD = 22.7 ± 16.9 mm in standard length (SL), n = 32] occurred in the upper reach of the estuary, while larger specimens (52.4 ± 26.2 mm SL, n = 18 and 51.5 ± 29.7 mm SL, n = 10, respectively) were found in the middle and lower reaches and none in the marine area. In B. humeralis and B. koilomatodon, only juveniles were caught except for one adult specimen each. Juveniles (8.9–16.5 mm SL, n = 79) of B. humeralis occurred in the upper and middle reaches and the marine area. B. koilomatodon juveniles (9.9–13.7 mm SL, n = 30) were distributed in all areas from the lower to upper reaches.     

Notes on the morphology of the early stage of the rare bramid genus Eumegistus

The morphology of the early stage of Eumegistus was described from three specimens [E. brevorti: 23.0 mm in standard length (SL) juvenile; E. illustris: 5.8 mm SL postflexion larva, and 40.0 mm SL juvenile] recently rediscovered in museum collections. Larval and juvenile pigmentation patterns were reported for the first time for this genus. The 5.8 mm SL postflexion larva of E. illustris had pigmentation on the head and anterior half of the body, through to the middle of the dorsal fin base. In larvae and juveniles of both species, the outer side of the pelvic fin was pigmented. The two juveniles possessed several spines on the lachrymal and protruding rays in the middle of the caudal fin. Although it is known previously that the notochord flexion occurs at 5.0–6.0 mm SL in E. brevorti, the reexamined 5.0 mm SL specimen had the notochord completely flexed. Furthermore, we could not confirm whether the previously studied 4.0 mm SL specimen was E. brevorti because it was badly damaged.     

Current status and ecological characteristics of the Chinese temperate bass Lateolabrax sp., an alien species in the western coastal waters of Japan

A total of 263 adult and preadult Chinese temperate bass Lateolabrax sp. caught at 20 locations in the coastal waters of western Japan from October 1999 to September 2008 were used for age, growth and maturity examinations. Examination of marginal increments of transverse sections of otoliths showed that rings (opaque zones) were formed once a year from spring to summer. According to the number of rings and the sampling month, ages were assigned to individuals. For males, we obtained the following von Bertalanffy growth equation: L(t) = 618{1 − e^{−0.420 (t + 0.273)}}. Females attain sizes over 600 mm SL mainly after 5 years of age and attain sizes of 850–1,000 mm SL at 8–10 years and over 1,100 mm SL about 15 years. Based on histological examinations of gonads and seasonal changes in gonadosomatic indices, potential spawning period was confirmed during mid-October to late January. In males, the minimum size and age at first maturity were estimated as 380 mm SL and 2 years old, respectively, though most males reach sexual maturity at 3–4 years old. Furthermore, female specimens at the mature or developing stages were over 470 mm SL and 4 years old.     

A new righteye flounder, Poecilopsetta multiradiata (Teleostei: Pleuronectiformes: Poecilopsettidae), from New Zealand and New Caledonia (South-West Pacific)

A new righteye flounder, Poecilopsetta multiradiata, is described from eight specimens (two males and six females) collected from deep waters (336–408 m) around New Zealand and New Caledonia (South-West Pacific). This new species is distinguished from its 14 congeners by the following combination of characters: high numbers of dorsal (70–73) and anal (58–62) fin rays, ca. 85–99 lateral-line scales, 31–32 caudal vertebrae, and a relatively shallow body depth of 36.9–41.9% SL.     

Leptocephalus larvae of Pterothrissus gissu collected from the Kuroshio–Oyashio transition region of the western North Pacific, with comments on its metamorphosis

 Pterothrissus gissu is a rare albulid fish that is distributed in deep water off Japan. This fish is known to pass through a leptocephalus larval stage, but only metamorphosed (after reaching the fully grown stage) specimens have been available. In this study, the premetamorphosis (before fully grown stage) leptocephalus larva of P. gissu is first described from 45 specimens (117.2–194.5 mm SL) collected by a pelagic otter trawl in the Kuroshio–Oyashio transition region of the western North Pacific in May 1995. Premetamorphosis leptocephalus larvae are characterized by having poorly developed fin rays except for the caudal fin, a translucent body, branched melanophores beneath the eye, and punctuate melanophores on the dorsal edge of the gut from the throat to the anus. Previously fully grown leptocephali were estimated to reach about 130 mm SL based on the size distributions of metamorphosing specimens. However, the present specimens show that fully grown leptocephali of P. gissu exceed 180 mm SL. Received: March 21, 2001 / Revised: March 19, 2002 / Accepted: April 15, 2002     

<Emphasis Type="Italic">Careproctus kidoi</Emphasis>, a new Arctic species of snailfish (Teleostei: Liparidae) from Baffin Bay

Careproctus kidoi sp. nov. is described from the Baffin Bay between Greenland and Canada, in the northern most part of the western North Atlantic. During a series of bottom trawl surveys conducted in 1988–2004, 22 specimens of an undescribed species of Careproctus were caught at depths between 952 and 1,487 m. It differs from Arctic and North Atlantic congeners in the combination of the characters: pectoral fin rays 21–26, dorsal fin rays 54–60, anal fin rays 50–54, vertebrae 61–64; sucking disc oval, 4.2–6.6% SL; teeth simple; pyloric coeca 3–12; head pore formula (2-6-7-1); color light to dark brown, stomach dusky to dark brown, peritoneum black. It is generally found in deeper waters than the sympatric C. reinhardti.     

<Emphasis Type="Italic">Glyptothorax dikrongensis</Emphasis>, a new species of catfish (Teleostei: Sisoridae) from Arunachal Pradesh,northeastern India

Glyptothorax dikrongensis, a new species of sisorid catfish from the Dikrong River in northeastern India, is described. Glyptothorax dikrongensis can be differentiated from all congeners, except G. indicus, G. rugimentum and G. obliquimaculatus, by the presence of an unculiferous patch on the posterior region of the lower lip, in between the inner mandibular-barbel bases, and unculiferous striae of the thoracic adhesive apparatus extending anteriorly onto the gular region. Glyptothorax dikrongensis is distinguished from G. indicus by the following combination of characters: equal distance between the posterior end of the pectoral-fin base and the pelvic-fin origin and between the pelvic-fin and the anal-fin origin (vs. distance between posterior end of pectoral-fin base and pelvic-fin origin greater than between pelvic-fin origin and anal-fin origin), and the pelvic-fin origin anterior to or almost at a vertical through the posterior end of the dorsal-fin base (vs. posterior to the dorsal-fin base). Glyptothorax dikrongensis is distinguished from G. rugimentum in lacking vertical bars on the body and caudal peduncle, and having a deeper caudal peduncle (8.4–9.2 vs. 6.1–7.6% SL) and a shorter dorsal-fin spine (10.1–11.1 vs. 15.2–18.6% SL). It is distinguished from G. obliquimaculatus in lacking dark, oblique blotches on the body, and in having a shorter dorsal-fin spine (10.1–11.1 vs. 13.4–16.4% SL).     

A new silverside, <Emphasis Type="Italic">Atherinomorus aetholepis</Emphasis> sp. nov., from the West Pacific (Atheriniformes: Atherinidae)

Atherinomorus aetholepis sp. nov. is described from the holotype and 51 paratypes, 44–72 mm in standard length, collected from Indonesian and Philippine waters. The species is similar to other congeners in general body appearance, especially A. duodecimalis and A. regina, in having a slender body, a tubercle on the posterior end of the dentary, and a narrow midlateral band, but clearly differing from them in having a long spatular outgrowth on the posterior margins of most of the predorsal and interdorsal scales. Additionally, the species differs from A. duodecimalis in having a more slender body [body depth 17–22 (mean 19) % SL vs. 19–25 (mean 22) % SL], more midlateral scales [37–40 (mean 38.4) vs. 35–38 (mean 36.6)], more total vertebrae [38–42 (mean 39.9) vs. 36–40 (mean 38.0)], and fewer lower gill rakers [18–22 (mean 20.2) vs. 20–25 (mean 22.3)], and from A. regina in having more anal fin soft rays (12–14 vs. 9–10). Electronic supplementary material to this article is available at and accessible to authorized users. Received: October 22, 2001 / Revised: March 14, 2002 / Accepted: March 26, 2002 An erratum to this article is available at .     

Channa nox, a new channid fish lacking a pelvic fin from Guangxi, China

 A new species of channid fish, genus Channa, is described from 7 specimens collected from the vicinity of Hepu, Guangxi Province, southern China. The new species, Channa nox, is distinguished from all other channid species by the following combination of characters: absence of pelvic fins, small rounded head (22.1%–26.8% SL), narrow interorbital width (19.6%–26.7% HL), short snout length (3.6%–5.1% SL), predorsal and prepectoral lengths (26.9%–28.4% SL and 24.8%–28.3% SL, respectively), 47–51 dorsal fin rays, 31–33 anal fin rays, 55–63 lateral line scales, 5.5–6.5 scales above lateral line, 9–13 cheek scales, 53–55 total vertebrae, 1 or 2 scale(s) on each side of lower jaw undersurface, the black upper half of body with 8–11 irregular (often anteriorly pointed V-shaped) bands or blotches, a large white-rimmed black ocellus on caudal peduncle and sparse white spots on the dark brown body and dorsal and caudal fins, as well as the shape of the hyomandibular process of the suprabranchial organs. Channa nox is sympatrically distributed with its morphologically most similar congener, C. asiatica. Received: January 18, 2001 / Revised: November 2, 2001 / Accepted: December 12, 2001     

Thysanophrys papillaris, a new species of flathead from the Andaman Sea and Northern Australia (Scorpaeniformes: Platycephalidae)

A new platycephalid,Thysanophrys papillaris, is described on the basis of six specimens (78–121 mm SL) collected from the Andaman Sea and off northern Australia (Timor and Arafura Seas). This new species can be distinguished from other congeners by the following combination of characters: presence of a single short papilla on upper surface of eye, longer snout, smaller body scales. 11 second dorsal-fin rays and 12 anal-fin rays, presence of four or more suborbital spines usually, branched short iris lappet, ctenoid lateral-line scales and interopercle not extended posteroventrally.     

Small-scale patterns in distribution and feeding of Atlantic mackerel (Scomber scombrus L.) larvae in the Celtic Sea with special regard to intra-cohort cannibalism

Short-term variability in vertical distribution and feeding of Atlantic mackerel (Scomber scombrus L.) larvae was investigated while tracking a larval patch over a 48-h period. The patch was repeatedly sampled and a total of 12,462 mackerel larvae were caught within the upper 100 m of the water column. Physical parameters were monitored at the same time. Larval length distribution showed a mode in the 3.0 mm standard length (SL) class (mean abundance of 3.0 mm larvae =75.34 per 100 m³, s=34.37). Highest densities occurred at 20–40 m depth. Larvae <5.0 mm SL were highly aggregated above the thermocline, while larvae ≥5.0 mm SL were more dispersed and tended to migrate below the thermocline. Gut contents of 1,177 mackerel larvae (2.9–9.7 mm SL) were analyzed. Feeding incidence, mean number (numerical intensity) and mean dry weight (weight-based intensity) of prey items per larval gut were significantly dependent on larval size. However, while weight-based feeding intensities continued to increase with larval length, numerical intensity peaked at 4–4.9 mm SL, indicating a shift in the larval diet. While first-feeding larvae relied most heavily on copepod nauplii and eggs, larvae ≥5.0 mm SL initiated piscivorous feeding. All identifiable fish larvae were Atlantic mackerel. Thus, the piscivory was cannibalism. Larval feeding incidence and numerical feeding intensities peaked during daytime and were reduced at night. Daily ration estimates for first-feeding mackerel larvae <4.0 mm SL were extremely low = 1.43% body dry weight, but increased dramatically at 5.0 mm SL, i.e., at the onset of cannibalism, reaching >50% body dry weight in larva ≥8.0 mm SL. Received in revised form: 31 October 2000 Electronic Publication     

Larval development of bigmouth manefish Caristius macropus (Perciformes: Caristiidae) from the western North Pacific

Larvae of bigmouth manefish Caristius macropus are described and illustrated on the basis of seven specimens (4.2–10.5 mm in body length) from the Kuroshio waters (0–60 m depth) and the transition waters (surface) between the Kuroshio and Oyashio fronts of the western North Pacific. The present larvae of C. macropus are distinguished from those of Paracaristius maderensis that inhabit the North Pacific by having 39–40 myomeres, 34 dorsal-fin rays, and 22 anal-fin rays. The present study, along with previous studies of the early life stages of caristiids, shows that larvae of the family may be defined by the following characters: body elongate in preflexion stage but becoming deep bodied and hatchet shaped after notochord flexion; anus located near vertical through base of pectoral fin; head large, without spination or serration; a distinct vertical band on the posterior tail throughout the larval stages, and two bands gradually appearing on the tail and trunk during the flexion and postflexion stages; and melanophores present around the notochord tip by the flexion stage. Adult C. macropus are found in the subarctic and temperate waters of the North Pacific; however, the present study and other occurrences of early life stages of the species probably indicate that C. macropus may spawn over a wide area in the North Pacific.     

<Emphasis Type="Italic">Epigonus cavaticus</Emphasis> (Teleostei: Perciformes), a new epigonid fish from Palau,western Central Pacific

A new epigonid fish, Epigonus cavaticus, is described on the basis of eight specimens (59.2–69.5 in standard length: SL) collected from a cave at depth 20 m, southern fringing reef of Ngemelis Island, Palau. The species differs from other congeners by having minute teeth on both jaws, no opercular spine, pyloric caeca 7–8, gill rakers 25–27, total pored lateral line scales 48–50, dorsal fin rays VII-I, 10–11 (mode VII-I, 10), pectoral fin rays 16, vertebrae 10 + 15, body depth 21.4–25.0% SL, pectoral fin length 22.7–24.6% SL, eye diameter 44.4–47.5% head length: HL, upper jaw length 40.2–42.5% HL. Four paratypes (63.7–66.8 mm SL) of the new species are female with mature gonads, it is the smallest in size at sexual maturity among the congeners.     

Developmental morphology of the cyprinid fish Tanichthys albonubes

Embryonic, larval, and juvenile development of a small cyprinid species, Tanichthys albonubes, is described from laboratory-reared specimens. The eggs, measuring 1.0–1.2 mm in diameter, were demersal, almost spherical in shape, transparent and unpigmented, with a pale yolk without oil globules. Hatching occurred 45–53 h after fertilization at 25.5°–26.9°C. The newly hatched larvae, measuring 2.2–2.6 mm in body length (BL), had melanophores on the head and body. In particular, a dark vertical streak occurring posterior to the otic capsule and melanophores above the eyes were distinctive. The yolk was completely absorbed at 3.4 mm BL. Notochord flexion was initiated at 5.0 mm BL and finished at 6.0 mm BL. Aggregate numbers of all fin rays were completed at 11 mm BL. Squamation was initiated at 8.4 mm BL and completed at 13 mm BL. Although the eggs of T. albonubes resembled those of other small danionin species, including Aphyocypris chinensis, Chela dadiburjori, Danio rerio, Devario malabaricus, Gobiocypris rarus, Hemigrammocypris rasborella, and Horadandia atukorali, they differed from those of A. chinensis, C. dadiburjori, G. rarus, and Horadandia atukorali in having a wider perivitelline space. The larvae and juveniles of T. albonubes were similar to those of the aforementioned seven species plus Danio albolineatus, Danio kerri, and Devario sp. (cf. D. aequipinnatus) in general morphology. However, the early life stage morphology of T. albonubes differed from them in having a dark vertical streak posterior to the otic capsule and melanophores above the eyes in the yolk sac larval stage, and a dark lateral streak with an unpigmented area just above the former on the body, a dark blotch on the caudal fin, and reddish dorsal, anal, and caudal fins during the postflexion larval and juvenile stages.