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1.
Early life stages of Artedidraco skottsbergi and A. shackletoni were collected off Adélie Land. The morphology and pigmentation pattern of nine larvae and juveniles of A. skottsbergi between 17.2 and 21.4 mm in standard length (SL), and of two juveniles of A. shackletoni measuring 25.1 mm SL were described. A. skottsbergi was characterized by a heavily pigmented body, except for the caudal peduncle, with distinctively dense pigmentation on the ventrolateral half of the body and caudal section (17.2–17.9 mm SL). Furthermore, they had no pigmentation on the pectoral fin base until they attained 21.4 mm SL. Juvenile A. shackletoni had a heavily pigmented body except for the ventral side of the abdomen and the anal fin base. The proximal part of the dorsal fin and most of the anal fin were covered with melanophores. Although knowledge of larval and juvenile Artedidraco species is limited, the distribution of melanophores on the fins, pectoral fin base and caudal peduncle at each developmental stage may be useful for species identification.  相似文献   

2.
Johnius (Johnius) majan sp. nov. is described on the basis of 8 specimens (117–158 mm in standard length) from Oman, Indian Ocean. The new species is distinguished from its congeners by the following combination of characters: black axillary spot on upper pectoral fin base; dorsal soft rays 29–32; anal soft rays 8; scales above lateral line 6, below 11; eye diameter 22.9–28.9% HL; interorbital width 32.0–38.0% HL; gill rakers 5–6 + 15–18 = 21–24; no mental barbel; last well developed pleural rib on 7th vertebra; swim bladder appendages 11; vertebrae 10 + 14 = 24.  相似文献   

3.
 This study redescribes Bregmaceros mcclellandi Thompson, 1840, based on one specimen (74.4 mm SL) from the Bay of Bengal and 66 specimens (30.0–84.7 mm SL) from Mumbai (Bombay), India, because the type specimens have apparently been lost. The present specimens are characterized by having black dorsal, pectoral, and caudal fins and show the following morphology: caudal fin slightly forked; body chromatophores present mainly at the dorsal part; no scales on cheek; vertebrae 52–55 (13–15 + 38–41); dorsal rays 52–59; anal rays 54–60; pectoral rays 18–20; caudal rays 27–31 (principal rays 14); transverse scales 14–15. In the 66 Mumbai specimens, it was confirmed that the distinctive black fin pigmentation developed sequentially with growth, with complete pigmentation first on the anterior lobe of the dorsal fin, then simultaneously on the posterior lobe of the dorsal fin, the caudal fin, and the pectoral fin, and last, on the anal fin. This species is known only from the Arabian Sea, Bay of Bengal, and Gulf of Thailand. A review of 16 nominal Bregmaceros species indicates that, besides B. mcclellandi, the distinctive dark fin pigmentation is found in B. atripinnis (Tickell), B. atlanticus Goode and Bean, B. japonicus Tanaka, and B. lanceolatus Shen. B. atripinnis is considered a junior synonym of B. mcclellandi, and the others are clearly distinct from B. mcclellandi. Comments are made on some of the characters to more fully characterize the species and for reference in future revisionary and phylogenetic studies. Received: June 17, 2002 / Revised: December 2, 2002 / Accepted: December 24, 2002  相似文献   

4.
A new loach, Oreonectes elongatus sp. nov. is described based on collections from Mulun Township, Huanjiang County, Guangxi in China. It is distinguished from its congeners by the combination of the following characters: most elongate body (body depth/SL 8.62–10.68%), blind, a forked caudal fin, obvious adipose dorsal crest and ventral crest; entire body naked and de-pigmented. Although the new species has a similar distribution with O. macrolepis, it can be distinguished by scales (absent in O. elongatus vs. present in O. macrolepis), shape of snout (elongate vs. round), the opposite position of the dorsal and pelvic fins origins (behind vs. front). The new species shares the same possession of dorsal and ventral crests, a forked caudal fin, eyeless, naked body and incomplete lateral line with O. translucens, but can be distinguished from the latter by caudal fin crest (more developed and translucent in O. translucens), longer anterior nostril tube and barbel, extreme of pectoral fin reaching 2/3 of the distance between origin of pectoral and pelvic fins, more vertebrae (4 + 38–39 vs. 4 + 32).  相似文献   

5.
Based on our reexamination of the 9 specimens including the neotype, Bregmaceros lanceolatus is recharacterized and diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dorsal surface of snout unpigmented or with a few chromatophores; isthmus pigmented with punctate chromatophores; two parapophyses on abdominal vertebrae; dorsal rays (D) 65–74; anal rays (A) 67–74; vertebrae (V) 58–61; longitudinal scales (LS) ca. 82–88; principal caudal rays (PC) 16–18; head length (HL)/standard length (SL) 14.0–15.5%; caudal peduncle depth/SL 3.2–4.2%. Based on 27 specimens, B. pseudolanceolatus sp. nov. is described. This species is closely similar to B. lanceolatus, but is diagnosed by the following combination of features: caudal fin rounded; scales present on gill cover; dense concentration of chromatophores on dorsal surface of snout; isthmus colorless; one board-like parapophysis on the last three abdominal vertebrae; D 58–64; A 58–67; V 52–55; LS ca. 68–77; PC 14–16; HL 15.5–18.4% SL; caudal peduncle depth 4.1–5.2% SL. Bregmaceros pseudolanceolatus is known from around the Taiwan Strait, southern East China Sea, South China Sea, Gulf of Thailand, Timor Sea, Arafura Sea, and eastern Bay of Bengal.  相似文献   

6.
We investigated the size at maturation, breeding season, and morphological development of larvae and juveniles of a freshwater pipefish Microphis leiaspis, which belongs to Gastrophori, collected from three rivers on the northern part of Okinawa-jima Island, Japan. The minimum size of brooding males was 105–123 mm in standard length (SL). The smallest mature female was estimated to be ca. 130 mm SL from the analysis of gonadosomatic index (GSI) and histological observations of gonads. The breeding season was estimated to be from June to December according to monthly changes in female GSI, histological observations of gonads, and monthly changes in the occurrence of brooding males. The number of eggs in the male brood pouch ranged from 75 to 241 (mean ± SD: 152 ± 52, n = 22). The male releases newly hatched larvae in freshwater areas. After newborns grow in the sea, they return to freshwater areas of the rivers and attain maturity. Microphis leiaspis was conformed to have an amphidromous life history. Notochord length of the released larvae was 6.1 mm, with a well-developed finfold. Larvae attained 11.1 mm SL, formation of the caudal and dorsal fin rays was complete, and the caudal fin became lozenge shaped at 30 days after the release, and juveniles reached 36.0 mm SL at 63 days after release. In the period between 30 and 63 days after the release, formation of all fins except the pectoral fins was completed, and caudal fin rays were extended and sector shaped with deep slits between each fin ray. The morphology of the released larvae of M. leiaspis is similar to that of Gastrophori species, and the morphology of juveniles similar to other species of Microphis.  相似文献   

7.
A new species of bitterling, Acheilognathus striatus sp. nov., is described on the basis of 57 specimens collected from the lower Yangtze River in Jiangxi Province, China. It can be distinguished from all congeners by the following combined characters: a pair of relatively long barbels, slightly longer than half of eye diameter; dorsal fin with three simple and 8–9 branched fin rays, anal fin with three simple and 7–8 branched fin rays; a black longitudinal stripe on body from the base of caudal peduncle, distinctly reaching anteriorly to the vertical line from the origin of dorsal fin, broader in males than in females; a scale distance between the longitudinal stripe and lateral line below the origin of dorsal fin; dorsal and anal fin margined with black band in males.  相似文献   

8.
The caudal fin represents a fundamental design feature of fishes and plays an important role in locomotor dynamics in fishes. The shape of caudal is an important parameter in traditional systematics. However, little is known about genes involved in the development of different forms of caudal fins. This study was conducted to identify and map quantitative trait loci (QTL) affecting the length of caudal fin and the ratio between tail length and standard body length in Asian seabass (Lates calcarifer). One F1 family containing 380 offspring was generated by crossing two unrelated individuals. One hundred and seventeen microsatellites almost evenly distributed along the whole genome were genotyped. Length of caudal fin at 90 days post-hatch was measured. QTL analysis detected six significant (genome-wide significant) and two suggestive (linkage-group-wide significant) QTL on seven linkage groups. The six significant QTL explained 5.5–16.6% of the phenotypic variance, suggesting these traits were controlled by multiple genes. Comparative genomics analysis identified several potential candidate genes for the length of caudal fin. The QTL for the length of caudal fin detected for the first time in marine fish may provide a starting point for the future identification of genes involved in the development of different forms of caudal fins in fishes.  相似文献   

9.
A new species of the genus Paracobitis, Paracobitis nanpanjiangensis is described from tributaries of the Nanpanjiang River drainage in China. It is distinguished from its congeners, except P. oligolepis and P. wujiangensis, by body scaleless or with rudimentary scales (caudal peduncle with several deeply embedded scales). It can be differentiated from P. wujiangensis by the complete lateral line (vs. incomplete), lower dorsal crest reaching the vertical of origin of anal fin (vs. shorter and higher dorsal crest not reaching the base of anal fin). It is distinguished from P. oligolepis by the following characters: branched dorsal fin with 81/2 (a few 91/2) rays (vs. 91/2), interspaces between bars in front of dorsal fin conspicuously thinner than those behind (vs. vermiform markings), dorsal head without vermiform markings or obscure (vs. clearly vermiform markings on dorsal head), vertebrae 4 + 36–38 (vs. 4 + 39–41).  相似文献   

10.
A new snailfish, Careproctus notosaikaiensis, is described on the basis of 6 specimens collected from the central part of the Sea of Japan, off Saikai, western coast of the Noto Peninsula, Ishikawa, Japan. The new species is distinguished from other congeners by the following combination of the characters: vertebrae 57–58, 10–12 abdominal and 46–48 caudal; dorsal-fin rays 52; anal-fin rays 46–47; principal caudal-fin rays 10; pectoral-fin rays 35–37; pectoral fin with a deep notch; proximal pectoral radials 4 (3 + 1), round; gill slit extending to pectoral-fin ray 4–7; teeth strongly trilobed; pleural ribs 2 pairs; 2 suprabranchial pores; chin pores paired in the same pit; pyloric caeca 20–29; dorsal and anal fins with dark margins and stomach black in preserved specimens.  相似文献   

11.
 A taxonomic review of seven-spined Polynemus species recognizes two species as valid: P. hornadayi Myers, 1936, currently known only from western Sarawak, Kalimantan, Malaysia, and P. paradiseus Linnaeus, 1758, distributed from India to Thailand and regarded as a senior synonym of P. aureus Hamilton, 1822, P. longifilis Cuvier in Cuvier and Valenciennes, 1829, P. risua Hamilton, 1822, and P. toposui Hamilton, 1822. Polynemus hornadayi differs from P. paradiseus in having a strongly protruded occipital profile (vs. nearly straight in the latter), lower counts of anal fin soft rays (mode 11 vs. 12) and gill rakers (26 vs. 32 or 33), higher counts of pectoral fin rays (18 vs. 17), scales above and below the lateral line (11 and 18 vs. 7 and 11, respectively), and pored lateral line scales (94 vs. 70), the fifth pectoral filament longest (vs. sixth), the fourth pectoral filament longer (extending well beyond the posterior central margin of the caudal fin vs. not reaching posterior central margin), a longer pectoral fin ray (posterior tip of pectoral fin reaching to midpoint of anal fin base vs. not reaching), a deeper maxilla posterior margin (mean 5% of SL vs. 4% of SL), and a well-developed swimbladder (vs. absent).  相似文献   

12.
A new loach species, named Triplophysa jianchuanensis, has been recognized in collections from Jianchuan in Dali Prefecture, Yunnan, China. Triplophysa jianchuanensis can be distinguished from the other Triplophysa species by the following combination of characteristics: smooth skin, scaleless; lateral line complete; head long (26.7–29.8% of SL); eyes large (25.9–31.0% of dorsal head length); snout shorter than postorbital length (26.9–30.1% of HL); middle of lower lip interrupted and forming a pair of furrows; lower jaw spoon-like with obtuse edge; posterior chamber of air bladder completely degenerated; intestines short, bending in zigzag-shape behind stomach; pelvic-fin tip not reaching anus; caudal fin emarginate; branched rays of dorsal fin 7; branched rays of caudal fin 16. A key to the known species of Triplophysa from the Lancangjiang River is provided.  相似文献   

13.
Chelidoperca tosaensis is described as a new species based on 84 specimens from Japan and the Philippines taken from depths of 60–302 m. The species can be distinguished from all known congeners by having the following combination of characters: scale rows between lateral line and base of spinous dorsal fin 3; pored lateral-line scales 37–42 (modally 39); scale rows in longitudinal series 39–43 (modally 40); no longitudinal dark stripe or row of dark blotches on body side. The new species is additionally characterized by having a combination of numerous, scattered, yellow spots on dorsal and anal fins with red streak or cluster of reddish spots over bases of about 4–6th dorsal-fin spines; large ocellated red spot with pinkish white border present on membrane between opercular spines; pelvic fin with middle area yellow with whitish spine, and whitish first, second and fifth soft rays; caudal fin with about three transverse rows of yellow spots centrally and posteriorly, two fan-shaped rows of red blotches on basal third, and a pair of white blotches with a pair of yellow blotches between white blotches on the base. Diagnostic characters of Chelidoperca stella, previously known only from its type locality in the Andaman Sea, are updated based on 12 specimens from Taiwan, the Gulf of Tonkin, Vietnam and the Philippines. These specimens represent the first records of the species from the Pacific Ocean.  相似文献   

14.
A new dextral flounder, Samariscus multiradiatus, is described from six specimens (four males and two females) collected in deep waters (296–430 m) around New Caledonia. The species is easily distinguished from its 16 congeners in having a combination of 85–91 dorsal fin rays, 67–72 anal fin rays, 5 pectoral fin rays, and 9 abdominal and 34–35 caudal vertebrae.  相似文献   

15.
Parakysis notialis sp. nov. is described from the Barito River drainage in southern Borneo. It can be distinguished from congeners in having a unique combination of the following characters: head length 26.5–27.0% SL, conical head, presence of median concavity on margin of lower lip, presence of laterosensory canal pore between inner and outer mandibular barbels, branched outer mandibular barbels, branches of inner mandibular barbels separated, deeply forked caudal fin with pointed lobes, 5 pectoral fin rays, 10 branched principal caudal fin rays, sparsely pigmented caudal fin, and absence of light brown saddle from base of posteriormost dorsal fin ray to caudal peduncle. Received: February 11, 2002 / Revised: September 4, 2002 / Accepted: October 11, 2002 Acknowledgments We thank Takashige Idei for the gift of the specimens of the new species, and Darrell Siebert (BMNH), David Catania (CAS), Karsten Hartel (MCZ), Douglas Nelson (UMMZ), and Kelvin Lim (ZRC) for permission to examine material under their care. Funding from a Block Grant from the Department of Ecology and Evolutionary Biology, University of Michigan and the Rackham School of Graduate Studies, University of Michigan provided financial support for this project. Correspondence to:Heok Hee Ng  相似文献   

16.
Morphological development, including the body proportions, fins, pigmentation and labyrinth organ, in laboratory-hatched larval and juvenile three-spot gourami Trichogaster trichopterus was described. In addition, some wild larval and juvenile specimens were observed for comparison. Body lengths of larvae and juveniles were 2.5 ± 0.1 mm just after hatching (day 0) and 9.2 ± 1.4 mm on day 22, reaching 20.4 ± 5.0 mm on day 40. Aggregate fin ray numbers attained their full complements in juveniles >11.9 mm BL. Preflexion larvae started feeding on day 3 following upper and lower jaw formation, the yolk being completely absorbed by day 11. Subsequently, oblong conical teeth appeared in postflexion larvae >6.4 mm BL (day 13). Melanophores on the body increased with growth, and a large spot started forming at the caudal margin of the body in flexion postlarvae >6.7 mm BL, followed by a second large spot positioned posteriorly on the midline in postflexion larvae >8.6 mm BL. The labyrinth organ differentiated in postflexion larvae >7.9 mm BL (day 19). For eye diameter and the first soft fin ray of pelvic fin length, the proportions in laboratory-reared specimens were smaller than those in wild specimens in 18.5–24.5 mm BL. The pigmentation pattern of laboratory-reared fish did not distinctively differ from that in the wild ones. Comparisons with larval and juvenile morphology of a congener T. pectoralis revealed several distinct differences, particularly in the numbers of myomeres, pigmentations and the proportional length of the first soft fin ray of the pelvic fin.  相似文献   

17.
 A pelagic juvenile (43.0 mm standard length) of the deep-sea gadiform fish Halargyreus johnsonii was collected by a larva net towed at depths from 200 m to 90 m at Suruga Bay, Japan. The specimen had an elongate body, eyes located dorsally on the head, a depressed anal fin, small bony tubercles on the lower jaw symphysis, elongate pelvic fin rays, and a pointed caudal fin. The body was silver with numerous small black spots. The gut was filled with a copepod, Pareuchaeta russelli, that is characterized by a surface to mesopelagic distribution. Received: May 30, 2002 / Revised: December 16, 2002 / Accepted: December 24, 2002  相似文献   

18.
Sphaerellothecium stereocaulorum sp. nov., Stigmidium beringicum sp. nov., Stigmidium stereocaulorum sp. nov. and goniocysts are described on Stereocaulon species from the northern Holarctic. Endococcus nanellus is reported new to Alaska and Mongolia. Taxonomical novelties Sphaerellothecium stereocaulorum Zhurb. & Triebel, Stigmidium beringicum Zhurb. & Triebel, Stigmidium stereocaulorum Zhurb. & Triebel.  相似文献   

19.
A new freshwater goby, Rhinogobius wuyanlingensis, was collected from Wuyanling National Natural Conservation Area, Taishun, Zhejiang Province, China. The species can be distinguished from all congeneric species by the following unique combination of features: second dorsal fin rays modally I, 8; anal fin rays I, 8; pectoral fin rays modally 18; longitudinal scale series 30–32; predorsal scales 7–9; vertebral count 10 + 17 = 27; body always with six longitudinal pinkish orange to grayish brown lines from dorsal to ventral region in male; cheek spotless; branchiostegal membrane deep grayish with 6–7 long, transverse deep red stripes in male; chin always deep grayish; first dorsal fin with two long black blotches on membranes anterior to third spinous ray in male; second dorsal fin whitish with three to four horizontal rows of light spots in male; caudal fin base with a large blackish-brown spot; and pectoral fin with a horizontal, median blackish brown line. An artificial key to all five nominal species with a high vertebral count (27–29) from Zhejiang Province from China is also provided.  相似文献   

20.
Two new species of ricefishes or buntingi, Adrianichthys roseni and Oryzias nebulosus, are described from Lake Poso, Sulawesi Tengah, Indonesia, bringing to 12 the number of endemic ricefishes known from Sulawesi. Adrianichthys roseni and its sole congener, A. kruyti, are distinguished from other relatively large-bodied ricefishes, Xenopoecilus, in having orbits that project beyond the dorsal profile of the head; paired preethmoid cartilages (versus single or absent in Xenopoecilus); and 13–16 (versus 8–13) dorsal fin rays. Also, as in A. kruyti, the lower jaw of A. roseni is enclosed in the upper jaw when the mouth is closed; however, the upper jaw is not as large and broadly expanded as in A. kruyti. Adrianichthys roseni differs further from A. kruyti in having fewer scales in a lateral series (approximately 63–65 versus 70–75), attaining a smaller maximum recorded standard length (90mm versus 109mm), and having the lateral process of the pelvic bone in line with the fifth, rather than the eighth, pleural rib. Oryzias nebulosus shares with O. nigrimas, also from Lake Poso, a unique sexual dichromatism in preserved specimens: adult males are dark gray to black, whereas females are a lighter grayish-yellow to brown. Relative to O. nigrimas, O. nebulosus is a small species (maximum recorded SL 33mm versus 51mm), with pelvic fins relatively anterior (lateral process of pelvic bone is in line with the third, fourth, or fifth, modally fourth, rather than the fourth or fifth, modally fifth, pleural rib), dorsal fin relatively anterior (origin above the 12–14th anal fin ray as opposed to the 15–17th anal fin ray), precaudal vertebrae 11–13, modally 12 (versus 13–14, modally 13), and relatively straight, narrow and slender (as opposed to curved, broad, and robust) ossified and cartilaginous portions of the gill arches. Endemic buntingi are threatened by introduction of exotic species, overfishing, and pollution. A conservation plan includes rearing native fishes for local use as ornamental fishes and possible reintroduction.  相似文献   

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