A Syngnathus species widely distributed in Chinese seas was permanently identified as Syngnathus acus by native ichthyologists, but the taxonomic description about this species was inadequate and lacking conclusively molecular evidence. To identify this species, 357 individuals of this species from the coastal waters of Dandong, Yantai, Qingdao and Zhoushan were collected and measured. Morphological results showed that these slender specimens were mainly brownish, usually mottled with pale. Standard length ranged from 117 mm to 213 mm with an average length of 180.3 mm. The above characters were consistent with S. schlegeli distributed in Japan but colored differently from and much smaller than typical S. acus reported in Europe. Thus, morphological studies revealed that this species was previously misidentified as S. acus and might be S. schlegeli in reality. In addition, a fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was also sequenced for species identification, and 15 COl sequences belonging to different Syngnathus species were also used for the molecular identification. CO1 sequences of our specimens had the minimum genetic distance from recognized S. schlegeli from Japan and clustered with it firstly. The phylogenetic analysis similarly suggested that the species previously identified as S. acus in the coastal waters of China was S. schlegeli actually.
Black rockfish 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 filtered seawater （salinity 30） for 24 h. Fluorescent marks were detected in otoliths （sagittae, asteriscus）, scales, fin rays （dorsal, pectoral, ventral, anal, and caudal fin rays）, and fin spines （dorsal, ventral, and anal fin spines） after a 60-d growth experiment. With the exception of 50-100 rng/L CAL, acceptable marks were produced in the otoliths and fin spines by all concentrations of CAL and ARS. In particular, marks were clearly visible under normal light in the sagittae, asteriscus, and fin spines offish immersed in 200 500 mg/L, 300-500 rag/L, and 200-500 mg/LARS, respectively. Scales and fin 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 fin rays）. The mark quality was highest （i.e., acceptable marks were observed in all sampled structures after immersion marking） in fish immersed in 150-250 mg/L CAL or 300-500 mg/LARS. In addition, there was no significant difference in survival and growth of marked fish compared with controls 60 d post-marking （P〉0.05）.
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 fluorescent 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 of200~00 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 rag/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）.
A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics： light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded： dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research.
