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1.
【目的】记述中国南海海域棘鲬属的一新纪录种,以厘定中国南海海域棘鲬属的分类。【方法】2019年4月于中国南海北部海域海南岛东南渔场采集棘鲬属样品,采用形态学鉴定方法研究其形态特征,描述其生态习性,编制中国棘鲬属分种检索表。【结果与结论】样品中有6尾为中国新纪录种——丝鳍棘鲬Hoplichthys filamentosus Matsubara&Ochiai,1950。主要特征:体延长,平扁,向后渐狭小,背缘低平,腹缘平直;背鳍VI,14~15;臀鳍17;胸鳍13+ⅲ;腹鳍Ⅰ-5;尾鳍17;侧线骨板27;鳃耙2+11~12;体具几条不明显深色横带;胸鳍具黑色斑点;第1背鳍分布黄色斑点,具黑色小点和黑边;第2背鳍中部分布黄色圆斑,每1鳍条根部具黄色圆斑;腹鳍白色,无斑纹;臀鳍无明显斑纹;尾鳍后缘具黑边,中部较随机分布黄色圆斑,下叶颜色较深。该种雌雄异形:1)雄性下颌骨腹外侧具棘,雌性则隐没皮下;2)雄性第2背鳍鳍条均显著延长呈丝状,雌性则无显著延长。  相似文献   

2.
Broodstock of Verasper moseri (Jordan and Gilbert) aged 3–4 years old were selected, and reinforced cultivation was conducted to promote maturation under controlled water temperature and photoperiod conditions. Fertilized eggs were obtained by artificial fertilization, and the development of embryos, larvae and juveniles was observed continuously. The results showed that the fertilized eggs of V. moseri were spherical, with transparent yolk and homogeneous bioplasm, and had no oil globule inside. The average diameter of the eggs was 1.77±0.02 mm. The eggs of V. moseri were buoyant in water with salinity above 35. The cleavage type was typical discoidal. Young pigment cells appeared when olfactory plates began to form. Hatching occurred at 187 h after fertilization at a water temperature of 8.5°C. The newly hatched larvae, floating on the water surface, were transparent with an average total length of 4.69±0.15 mm. During the cultivation period, when the water temperature was raised from 9 to 14.5°C, 4-day old larvae showed more melanophores on the body surface, making the larvae gray in color. The pectoral fins began to develop, which enabled the larvae to swim horizontally and in a lively manner. On days 7–8, the digestive duct formed. The yolk sac was small and black. The yolk sac was absorbed on day 11. Larvae took food actively, and body length and body height clearly increased. The rudiments of dorsal and anal fin pterygiophores were discernible and caudal fin ray elements formed on day 19. On day 24, the larval notochord flexed upwards, and the rays of unpaired fins began to differentiate. Pigment cells converged on the dorsal and anal fin rays, and the mastoid teeth on the mandible appeared. On day 29, the left eyes of juveniles began to move upwards. Depigmentation began in some juveniles and they became sandy brown in color on day 37. Most juveniles began to settle on the bottom of the tank. The left eyes of juveniles migrated completely to the right side on day 50, when the average body length attained 2.5±0.18 cm, and juveniles accomplished metamorphosis to young. The embryonic and larval characters of several flounder species are compared.  相似文献   

3.
Two new species of the genus Cobitis from southern China, C. hereromacula from the Luohe River in Guangdong Province and C. baishagensis from the Nandujiang River in Hainan Province, are described and illustrated here. C. hereromacula can be distinguished from its congeners by possessing the following combination of characteristics: absence of the second and third pigmentary zones of Gambetta; 13–16 oval blotches on the dorsum and 10–13 vertical, elongated triangular blotches below the midlateral line with more than 20 vertical dark brown bars between them; 6–7 narrow rows of dark spots on the caudal fin; a vertical oval spot smaller than the eye diameter on the upper part of the caudal peduncle; pointed mental lobes of the lower lip pointed with a slightly filiform tip; one slender and long needle-shaped lamina circularis at the base of the first branched ray of the male pectoral fins. C. baishagensis can be distinguished from its congeners by the fourth Gambetta zone being covered by 10–12 transverse elongated blotches; 4–5 narrow rows of dark spots on the caudal fin; a vertical blotch smaller than the eye diameter on the upper part of the caudal peduncle; males with a slender and long needle-shaped lamina circularis at the second branched pectoral fin ray in males; large scales with a slightly large focal zone; undeveloped mental lobes with a lower lip that does not end posteriorly in a filiform tip.  相似文献   

4.
5.
We collected leiognathid fishes from the Hainan Island and Beibu Gulf between November 2007 and December 2008. Ten of these specimens were identified as Nuchequula blochii (Valenciennes 1835), which is the first record of this species in China’s waters. These specimens are distinguished by the combination of these characteristics: breast fully scaled, cheek naked, anteroventral profile of the lower jaw almost straight, a conspicuous dark blotch distally on the anterior part of spinous portion of dorsal fin, a yellow blotch distally on posterior part of spinous portion of dorsal fin, and a dark blotch on nape. This paper reviews the genus Nuchequula and describes three species that occur in China’s waters.  相似文献   

6.
This study investigated the embryonic development of Maldives clownfish Amphiprion nigripes under natural conditions (28 - 30℃) at a lagoon of Agatti Island, Lakshadweep, India. The newly deposited fish egg was capsule-shaped and orange-red, with a (0.73 ± 0.04) mm3 yolk containing 5 - 10 fat globules. The embryonic development of fertilized eggs was divided into 26 stages and the time elapsing for each stage was recorded. Results showed that the cleavage was rapid, with the first division observed 1 h 20 min after fertilization. Blastulation occurred 4 h later, followed by gastrulation 12 h after fertilization, with a yolk volume of (0.61 ± 0.06) mm3. The organogenesis process started 22 h after fertilization when the blastopores closed and notochord formation began. The embryonic stage was recorded 24 h later, with the appearance of forebrain, midbrain, hindbrain, melanophores on yolk-sac and 22 somites, and a decreased yolk volume of (0.54 ± 0.08) mm3. Other organs developed well 31 h after fertilization, whereas the heart started beating and blood circulation began 78 h later. Red pigmentation (erytrophores) appeared 96 h after fertilization, with a small yolk volume of (0.22 ± 0.02) mm3. Mouth developed well and eyes were noticeable 120 h later, with head, pectoral fin and tail frequently moving 144 h after fertilization. The embryo reached the pre-hatching stage 168 h later and started to hatch after 170 - 180 h incubation. This study first detailed the embryonic development and yolk absorption of A. nigripes under natural conditions.  相似文献   

7.
Black rockfi sh Sebastes schlegelii juveniles(30–40 mm total length) were immersed in a range of calcein(CAL) solutions at concentrations ranging from 50 to 250 mg/L and alizarin red S(ARS) solutions at concentrations ranging from 100 to 500 mg/L in fi ltered seawater(salinity 30) for 24 h. Fluorescent marks were detected in otoliths(sagittae, asteriscus), scales, fi n rays(dorsal, pectoral, ventral, anal, and caudal fi n rays), and fi n spines(dorsal, ventral, and anal fi n spines) after a 60-d growth experiment. With the exception of 50–100 mg/L CAL, acceptable marks were produced in the otoliths and fi n spines by all concentrations of CAL and ARS. In particular, marks were clearly visible under normal light in the sagittae, asteriscus, and fi n spines of fi sh immersed in 200–500 mg/L, 300–500 mg/L, and 200–500 mg/L ARS, respectively. Scales and fi n rays had acceptable marks at much higher concentrations(≥50 mg/L CAL, ≥300 mg/L ARS for scales and ≥50 mg/L CAL, ≥200 mg/L ARS for fi n rays). The mark quality was highest(i.e., acceptable marks were observed in all sampled structures after immersion marking) in fi sh immersed in 150–250 mg/L CAL or 300–500 mg/L ARS. In addition, there was no signifi cant difference in survival and growth of marked fi sh compared with controls 60 d post-marking( P 0.05).  相似文献   

8.
We tested the utility of chemical marking techniques in the juvenile black rockfish Sebastes schlegelii. Juveniles(30–40 mm total length) were immersed in a range of tetracycline hydrochloride(TC) solutions at concentrations ranging from 300 to 500 mg/L, and alizarin complexone(ALC) solutions at concentrations ranging from 200 to 400 mg/L in filtered sea water(salinity of 30) for 24 h, respectively. Otoliths(sagittae, asteriscus), scales, fin rays(dorsal, pectoral, ventral, anal, and caudal fin rays), and fin spines(dorsal, ventral, and anal fin spines) were sampled and used to detect fl uorescent marks after a 60-day growth experiment. With the exception of 300 mg/L TC, acceptable marks were produced in the otoliths and fin spines by all concentrations of TC and ALC. In particular, we observed clearly visible marks in the sagittae, asteriscus, and fin spines under normal light at concentrations of 200–400 mg/L, 250–400 mg/L, and 250–400 mg/L ALC, respectively. Scales and fin rays had acceptable marks at much higher concentrations(≥350 mg/L TC, ≥250 mg/L ALC for scales and ≥350 mg/L TC, ≥300 mg/L ALC for fin rays). The best mark quality(i.e., acceptable marks were observed in all sampled structures after immersion marking) were obtained following immersion in TC at between 350–500 mg/L, and ALC between 300–400 mg/L. In addition, there was no significant difference in survival and growth of TC and ALC marked fish compared to their controls up to 60 days post-marking( P 0.05).  相似文献   

9.
Loach (Misgurnus anguillicaudatus) is a commercially important fish in China and an ideal aquaculture species. However, culturists experience high larval and juvenile mortality during mass production. To provide insight into ways to improve larviculture techniques, we describe the morphological characteristics and behavior of loach during the larval and early juvenile stages. Yolksae larvae ranged from 2.8 to 4.0 mm body length (BL) between days 0 to 4; preflexion larvae ranged from 3.6 to 5.5 mm BL between days 4 to 6; flexion larvae ranged from 4.8 to 8.1 mm BL between days 5 and 14; and post-flexion larvae ranged from 7. l to 15.7 mm BL between days 11 to 27; the minimum length and age of juveniles was 14.1 mm BL and 23 d, respectively. Loach are demersal from hatch through to the early juvenile stages. A suite of morphological characteristics (e.g., external gill filament and ventral mouth opening) and behavioral traits have developed to adapt to demersal living. We observed positive allometric growth in eye diameter, head length, head height, and pectoral fin length during the early larval stages, reflecting the priorities in the development of the organs essential for survival. Our results provide a basis for developing techniques to improve the survival of larval and juvenile loach during mass production.  相似文献   

10.
2012年12月3日,在渤海海峡的蓬莱近海浅水海域捕获雄性成体鱼1尾,该鱼体长34 cm,体高18cm,体长为体高的1.9倍,体宽4.5 cm,头长12.5 cm,体长为头长的2.7倍,尾柄长4.5 cm,体光滑无鳞。管状侧线前半部弧形,后半部平直,行于体中央。棘状骨板沿背鳍基底两侧各12块,臀鳍基底两侧各8块,每一骨板中央具1棘,向后;胸部6块,自第3骨板开始分左右两行;腹部7块,自第2骨板开始分左右两行,胸腹部骨板棘小,形成锯齿缘。背鳍1个,鳍棘部与鳍条部之间有一深缺刻;鳍棘细长,棘间鳍膜延长成丝状,最长超过尾鳍末端。据其形态特征和测量值,鉴定为云纹亚海鲂(Zenopsis nebulosa Temminck et Schlegel,1847),为该海域首次记录。  相似文献   

11.
The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus (Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power model was estimated for the length-weight relationship during the early life stages. Positive allometric growth for the head segment, trunk length, tail length and eye diameter was also found in the early life stages, while body depth, tail depth, tail fin length, pectoral fin length and barbel length displayed a negative coefficient. During the subsequent early developmental stage, the growth coefficients showed a clear and common tendency towards isometry for all measured body ratios. The allometric growth changes in Chinese loach during the early stage are possibly the result of selective organogenesis directed towards survival priorities.  相似文献   

12.
This paper deals with population identification ofParargyrops edita Tanaka. Samples of spawning stocks were collected from Niushan-Penghu, Minnan-Taiwan shoal (Southern Fujian-Taiwan shoal) and Beibu Gulf during the spawning period 1981–1982. Morphological characters, both meristic and morphometric, are counted and measured respectively. The stock concept and intraspecific categories have been discussed. Some meristic characters as the number of left or right ventral fin spine, right ventral fin rays and abdominal vertebrae of this fish may be constant, others as the numbers of left or right pectoral fin rays and gill-rakers may have obvious geographical variation. Morphological characters have not attained the level of subspecific distinctness, no sub-species could be found among these stocks by means of coefficient of difference (C.D.). Basing upon the comparative analysis ofM diff, the authors consider that stocks of Minnan-Taiwan shoal and Niushan-Penghu belong to the same local population, Taiwan Strait local population. By means of the discriminant function analysis and linear relationship analysis, statistical differences will be found to exist in meristic characters between the stock of Minnan-Taiwan shoal and that of Niushan-Penghu, so that the two are virtually different stocks or subpopulations. The stock of Beibu Gulf belongs to another called the Beibu Gulf local population. These two local populations are of allopatric distribution and show statistically significant difference between themselves. Among these stocks, the Minnan-Taiwan shoal stock is strongly influenced by the much more complicated environmental conditions of the mixed boundary region of the subtropical Sino-Japanese Subregion in the north and the tropical Indo-Malayan Subregion in the south. Thus its coefficient of variability (C.V.) is greater than those of the other two in the mean values of various meristic characters. This paper was published in Chinese inOceanologia et Limnologia Sinica 14 (6): 511–520.  相似文献   

13.
Requirement for dietary n−3 HUFA (n−3 highly unsaturated fatty acid) for growth and survival of black sea bream (Sparus macrocephalus) larvae was studied using rotifers andArtemia at various levels of n−3 HUFA. Five treatments with rotifers andArtemia differing in n−3 HUFA were prepared by enriching them with various oil emulsions. Results indicated that dietary n−3 HUFA significantly influence fish n−3 HUFA levels and are essential for growth and survival of black sea bream larvae. The results also indicated that the incorporation of n−3HUFA TG (triacylglycerols) into tissues of larval black sea bream was more effective from natural fish oil in comparison with n−3 HUFA fatty acid ethyl esters from ethyl-esterified oil. Project No. 39770588 supported by the NSFC.  相似文献   

14.
Jiao  Shuang  Tan  Xungang  You  Feng  Zhang  Shujing  Pang  Qiuxiang 《中国海洋湖沼学报》2023,41(1):280-289

Insulin-like growth factors (IGFs) are key regulators of development and growth. Here, we characterized the igf2 gene from olive flounder (Paralichthys olivaceus) and determined its temporal and spatial expression. We set up an in-vitro protein expression system in eukaryotic human embryonic kidney (HEK293T) cells and explored its effects on cell proliferation. The flounder igf2 cDNA contained a 648-bp open reading frame (ORF) encoding a protein of 215 amino acids (aa), which spanned the complete signal peptide (47 aa), mature peptide (70 aa), and E domain (98 aa). In adult flounder, igf2 mRNA was detected in all selected tissues. In early development, igf2 mRNA was detected throughout development from unfertilized eggs to hatching-stage embryos. In-situ hybridization analysis indicated that igf2 mRNA was specially expressed in the brain region, floor plate, hypochord, otic vesicle, and pectoral fin during embryogenesis. Western blotting analysis indicated that the soluble recombinant flounder IGF2 protein was successfully produced through eukaryotic expression in HEK293T cells. In addition, the recombinant IGF2 protein significantly promoted the proliferation of human cervical carcinoma (HeLa) and HEK293T cells. These results provide new information about the structural and functional conservation, expression patterns, and biological activity of the igf2 in teleosts.

  相似文献   

15.
描记采于贵州茂兰自然保护区一洞穴的盲副鳅一新种,命名为茂兰盲副鳅Paracobitis maolanensisLi,RanetChen sp nov。该种与产于该县的长须盲副鳅Paracobitis longibarbatusChen,YangetSket(1998)的区别为:①口须纤弱而不是发达;②鼻瓣不成须状;而不是鼻瓣发育成鼻须。③胸鳍较长,后伸接近腹鳍起点且形态特殊;④尾鳍深叉;⑤臀鳍条ii,5;而不是ii,6。新种与分布于广西的后鳍盲副鳅Paracobitis posterodarsalusLi,RaoetChen的区别为:①背鳍起点与腹鳍起点相对;而不是在整个腹鳍之后;②口须纤弱鼻瓣不呈鼻须;而不是口须发达,鼻瓣发育成鼻须;③背鳍条iii,8;而不是iii,6;④臀鳍条ii,5;而不是ii,4;⑤胸鳍长而形态特殊。  相似文献   

16.
描记采于贵州省茂兰自然保护区境内一洞穴的中国野鲮亚科(Labeoninae)一新属长臀鲮属Longanalus,spnov和一个新种大鳍长臀鲮Longanalus macrochiroussp nov。新属以臀鳍分枝鳍条为7根等特征,区别于该亚科所有属;新种以偶鳍发达,胸鳍后伸达到腹鳍基,腹鳍后伸超过臀鳍起点等显著特征命名大鳍长臀鲮。  相似文献   

17.
The trophic ecology of the small yellow croaker (Larimichthys polyactis) was studied using stable isotope analyses. Samples were collected from July to September 2009 and 34 individuals from eight sites were examined for stable carbon and nitrogen isotopes. Stable carbon isotope ratios (δ13C) ranged from -20.67 to -15.43, while stable nitrogen isotope ratios (δ15N) ranged 9.18-12.23. The relationship between δ13C and δ15N suggested high resource partitioning in the sampling area. Significant differences in stable isotope values among the eight sampling sites may be linked to environmental diversities involving various physical processes (such as ocean current, wind and tide) and different carbon sources. Furthermore, the stable isotope ratios may also explain the ontogenetic variability in diet and feeding, because δ13C and δ15N varied significantly with increasing body size. The findings are consistent with other studies on diet analyses in small yellow croaker. It was also demonstrated that stable isotope analysis could be used to estimate the trophic characters of small yellow croaker in feeding patterns and migrating habits.  相似文献   

18.
张多文 《山东国土资源》2004,20(2):29-33,40
汶东凹陷古近系分为古新世固城组和始新世大汶口组。大汶口组又分上、中、下3段,相应有3个化石组合带。从地震反射看,该凹陷内自下而上呈5组反射波特征。以古近纪地层特征为基础,结合构造演化分析认为:固城组为干旱气候条件下的山麓洪积相沉积,大汶口组下段为干旱条件下浅湖相沉积,大汶口组中段为逐渐湿润条件下的氧化一还原湖相沉积,大汶口组上段为潮湿气候条件下的还原湖相沉积。  相似文献   

19.
20.
Dietary leucine requirement for juvenile large yellow croaker, Pseudosciaena crocea Richardson 1846 (initial body weight 6.0 g ± 0.1 g) was determined using dose-response method. Six isonitogenous (crude protein 43%) and isoenergetic (19 kJ g−1) practical diets containing six levels of leucine (Diets 1–6) ranging from 1.23% to 4.80% (dry matter) were made at about 0.7% increment of leucine. Equal amino acid nitrogen was maintained by replacing leucine with glutamic acid. Triplicate groups of 60 individuals were fed to apparent satiation by hand twice daily (05:00 and 17:30). The water temperature was 26–32°C, salinity 26–30 and dissolved oxygen approximately 7 mg L−1 during the experimental period. Final weight (FW) of large yellow croaker initially increased with increasing level of dietary leucine but then decreased at further higher level of leucine. The highest FW was obtained in fish fed diet with 3.30% Leucine (Diet 4). FW of fish fed the diet with 4.80% Leucine (Diet 6) was significantly lower than those fed Diet 4. However, no significant differences were observed between the other dietary treatments. Feed efficiency (FE) and whole body composition were independent of dietary leucine contents (P > 0.05). The results indicated that leucine was essential for growth of juvenile large yellow croaker. On the basis of FW, the optimum dietary leucine requirement for juvenile large yellow croaker was estimated to be 2.92% of dry matter (6.79% of dietary protein).  相似文献   

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