DNA barcoding of coral reef fishes from Chuuk State, Micronesia.

The fish diversity of Chuuk Micronesia is currently under threat due to rapid changes in the coral reef ecosystem. Thus, accurate fish identification using DNA barcodes is fundamental for exploring species biodiversity and resource protection. In this study, we analyzed 162 fish mitochondrial DNA cytochrome c oxidase I (COI) barcodes from Chuuk Micronesia. Consequently, we identified 95 species from 53 genera in 26 families and seven orders. The average Kimura 2-parameter genetic distances within species, genera, families, and orders were calculated as 0.17%, 11.78%, 15.63%, and 21.90%, respectively. Also, we have utilized DNA barcodes to perform genetic divergence and phylogenetic analysis of families recognized as dominant groups in Chuuk State. Our findings confirm that DNA barcodes using COI are an effective approach in identifying coral reef fish species. We anticipate that the results of this study will provide baseline data for the protection of coral reef fish biodiversity at Chuuk Micronesia.

Complete mitochondrial genome of the mottled skate: Raja pulchra (Rajiformes, Rajidae).

The complete sequence of mitochondrial DNA of a mottled skate, Raja pulchra was sequenced as being circular molecules of 16,907 bp including 2 rRNA, 22 tRNA, 13 protein-coding genes (PCGs), and an AT-rich control region. The organization of the PCGs is the same as those found in other Rajidae species. The nucleotide of L-strand is composed of 29.8% A, 28.0% C, 27.9% T, and 14.3% G with a bias toward A + T slightly. Twelve of 13 PCGs are initiated by the ATG codon while COX1 starts with GTG. Only ND4 harbors the incomplete termination codon, TA. All tRNA genes have a typical clover-leaf structure of mitochondrial tRNA with the exception of [Formula: see text] which has a reduced DHU arm. This mitogenome will provide essential information for better phylogenetic resolution and precision of the family Rajidae and the genus Raja as well as for establishment of a fish stock recovery plan of the species.

Complete mitochondrial genome of Sebastes vulpes (Scorpaenidae, Scorpaeniformes) from the East Sea, Korea.

Sebastes vulpes is considered a valid species despite the presence of extensive hybrids. To obtain the basic genetic intraspecific structure, we analyzed the complete mitogenome of S. vulpes using next-generation sequencing. The complete mitogenome was 16,462 bp in length containing 13 protein-coding genes (PCGs), 2 rRNAs, 22 tRNAs and 1 control region. The complete mitogenome comprised 27.7% A, 26.5% T, 17.1% G and 28.6% C, showing a minor AT bias (54.3%). The initial codon in all PCGs was ATG, excluding COX1 (GTG). The majority of stop codons in the PCGs were TAA, excluding ND1 and ND3 (TAG), ND4 (AGA) and Cytb (incomplete termination codon, T). All tRNAs had a typical cloverleaf structure, excluding tRNA(Ser (AGY)), which lacked the DHU arm. The complete mitogenome of S. vulpes can be used to study hybridisation and on-going speciation.

The complete mitochondrial genome of the dark-banded rockfish Sebastes inermis (Scorpaenidae, Scorpaeniformes).

The complete mitochondrial genome of the dark-banded rockfish Sebastes inermis was determined using next-generation sequencing, including Sanger sequencing. The full genome was 16,504 bp in length, including 2 rRNA, 22 tRNA and 13 protein-coding genes (PCGs), as well as the control region. The genome was 27.8% A, 26.8% T, 17.1% G and 28.3% C, showing a slight AT bias (54.6%). All PCGs started with an ATG initial codon, except for COX1, which started with a GTG. The stop codon of all PCGs was a TAR, except for Cytb, which contained an incomplete termination codon, T. All tRNAs had the typical clover-leaf structure except tRNA(Ser (AGY)), which lacked the DHU arm. The complete mitogenome of S. inermis will aid the identification and genetic population studies on the genus Sebastes.

A new species of parasitic copepod Nothobomolochus and redescription of Orbitacolax hapalogenyos (Yamaguti and Yamasu, 1959) (Cyclopoida: Bomolochidae) off Iraq.

A new species of bomolochid copepod Nothobomolochus ilhoikimi sp. n., (Cyclopoida), is described based on adult females collected from the gills of hilsa shad Tenualosa ilisha (Hamilton) (Actinopterygii, Clupeidae) captured in waters off Iraq. The new species differs from its congeners by having the following combination of characters in the adult female: 1) anal somite not spinulate; 2) paragnath blunt and robust; 3) maxilla with slender proximal segment and distal segment with 2 accessory processes terminally; 4) the distal exopodal segment of leg 1 with 3 small spines; and 5) the terminal endopodal segment of leg 4 carrying one long and one short spine. It closely resembles N. triceros (Bassett-Smith, 1898) but prominently differs in above features and also in host specificity. In addition, another bomolochid Orbitacolax hapalogenyos (Yamaguti and Yamasu, 1959) is redescribed based on material collected from Japanese threadfin bream Nemipterus japonicus (Bloch) (Perciformes, Nemipteridae) captured in waters off Iraq. Two species clusters, the hapalogenyos and the analogus groups are recognized in this genus.

Monogeneans (Platyhelminthes) from marine fishes of Tongyeong, Korea.

Monogeneans (Platyhelminthes) mostly parasitize on fins, skin and gills of fishes. In Korea, the study on monogeneans is limited, although, fishes are frequently encountered with severe infection of monogeneans. Hence, some of ranched and wild fishes were collected from Tongyeong marine living resources research and conservation center, southern part of Korea to screen and understand the infection of monogeneans. All three fish hosts were found with the infection of monogeneans including five species from four different families. They are: (1) Anoplodiscus spari Yamaguti (Publ Seto Mar Biol Lab Kyoto Univ 7:53-88, 1958) (Anoplodiscidae) from the fins and body surface of blackhead seabream Acanthopagrus schlegelii schlegelii (Bleeker); (2) A. tai Ogawa (Fish Pathol 29:5-10, 1994) from the fins of red seabream Pagrus major (Temminck and Schlegel); (3) Benedenia sekii Yamaguti (Studies on the helminth fauna of Japan. Part 19. Fourteen new ectoparasitic trematodes of fishes. Published by the author, Kyoto, 1937), Meserve (Rep Allan Hancock Paci Exped (1932-1937) 2:31-89, 1938) (Capsalidae) from the body surface of P. major; (4) Choricotyle elongata Goto (J Coll Sci Imp Univ Tokyo 8:1-273, 1894) (Diclidophoridae) from the gills of P. major; (5) Udonella fugu Freeman and Ogawa (Int J Parasitol 40:255-264, 2010) (Udonellidae) hyperparasitized on the body of parasitic copepod Pseudocaligus fugu (Yamaguti 1936) (Caligidae) infecting the wild grass puffer Takifugu niphobles (Jordan and Snyder). Capsalids are commonly reported in Korea, except B. sekii, however, other reported genera are uncommon. Hence, all reported monogeneans are considered as a first record from Korea.

Three new records of copepods (Siphonostomatoida) parasitic on marine fishes of Iraq, including the relegation of two species of Lernanthropinus to Lernanthropinus temminckii (von Nordmann, 1864).

Three parasitic copepods (Siphonostomatoida) belonging to three different genera were recovered from marine fishes of Iraq, and are listed here as new records. The sea lice Caligus epinepheli Yamaguti, 1936 (Caligidae) was collected from the Japanese threadfin bream, Nemipterus japonicus (Bloch). It had been frequently reported from teleost fishes around the world. The second record, comprising male and female, was another caligid, rarely caught from fishes - Hermilius longicornis Bassett-Smith, 1898, collected from the giant catfish, Netuma thalassina (Rüppell). This paper features the first description of the male of the latter species. The third record was the lernanthropid, Lernanthropinus temminckii (von Nordmann, 1864) (Lernanthropidae), redescribed based on the specimens collected from the greater lizard fish, Saurida tumbil (Bloch) (Synodontidae). In order to clarify its taxonomic status, our specimen was compared with the holotype of L. gibbosus (Pillai, 1964) from the collections of Zoological Survey of India, Kolkata, and the syntypes of L. sauridae Do in Ho and Do, 1985 and L. temminckii from the collections of the Smithsonian Institution, Washington D.C. We found similarities in the morphology of the body, mouthparts, and legs 1-4 in three above-mentioned species. The prominent feature, the setation pattern of legs 1 and 2 was similar in all the female specimens examined. In the light of this, we formally relegate L. gibbosus and L. sauridae to synonymy with L. temminckii. Another important similarity is that Lernanthropinus gibbosus, L. sauridae, and L. temminckii have exclusively been parasitic on lizardfishes (Synodontidae). The attachment site of all three copepods reported form Iraq were the gill filaments.

Complete mitochondrial genome of sea urchin: Hemicentrotus pulcherrimus (Camarodonta, Strongylocentrotidae).

The complete mitochondrial genome of sea urchin Hemicentrotus pulcherrimus (A. Agassiz, 1863) is determined. The genome is a circular molecule of 15,705 bp in length and the gene content and order are identical to those of other strongylocentrotid species. Lengths of all protein coding genes (PCGs) are identical to those of M. nudus. S. droebachiensis and S. pallidus but ND6 has a deletion of 3 amino acids at the C-terminal. The nucleotide composition of the genome shows a bias toward A + T (59.8%) and the A + T bias in PCGs (59.4%) is slightly higher than the other strongylocentrotid species. The mitogenome of H. pulcherrimus provides genomic information of the single species genus, Hemicentrotus and helps understand the genetic relationship and the evolution of the genus in relation to the other genera of the family Strongylocentrotidae.

The caligid life cycle: new evidence from Lepeophtheirus elegans reconciles the cycles of Caligus and Lepeophtheirus (Copepoda: Caligidae).

The developmental stages of the sea louse Lepeophtheirus elegans (Copepoda: Caligidae) are described from material collected from marine ranched Korean rockfish, Sebastes schlegelii. In L. elegans, setal number on the proximal segment of the antennule increases from 3 in the copepodid to 27 in the adult. Using the number of setae as a stage marker supports the inference that the post-naupliar phase of the life cycle comprises six stages: copepodid, chalimus I, chalimus II, pre-adult I, pre-adult II, and the adult. We observed variation in body length in both of the chalimus stages which we consider represents an early expression of sexual size dimorphism. We interpret the larger specimens of chalimus I as putative females, and the smaller as putative males; similarly with chalimus II, larger specimens are putative females and the smaller are males. Two patterns of life cycle are currently recognized within the Caligidae but the evidence presented here reconciles the two. We conclude that the typical caligid life cycle comprises only eight stages: two naupliar, one copepodid, and four chalimus stages preceding the adult in Caligus, but with the four chalimus stages represented by two chalimus and two pre-adult stages in Lepeophtheirus. This is a profound change with significant implications for the aquaculture industry, given that lice monitoring protocols include counts of chalimus stages and use temperature to predict when they will moult into the more pathogenic, mobile pre-adults. Lice management strategies must be tailored to the precise life cycle of the parasite.

Induced Morphological Changes in Larval Rock Bream, Oplegnathus fasciatus, under Starvation.

Morphological changes in the reared rock bream, Oplegnathus fasciatus, from hatching to six days after hatching were examined during the early growth stage under starvation. All the larvae died within five days when feeding was delayed for three days after hatching. These results imply that initial larval food should be supplied within two days of hatching. Changes in the pectoral angle and the ratios of eye height to head height, gut height to standard length, and gut height to myotome height in the rock bream are alternative indicators for the identification of starving fish. These indicators might prove useful in evaluating the successful transition from endogenous to exogenous feeding in this species.

Caligus sclerotinosus (Copepoda: Caligidae), a serious pest of cultured red seabream Pagrus major (Sparidae) in Korea.

Caligid copepods (Crustacea) known as sea lice are pests of cultured fish, causing serious diseases and economic losses in fish aquaculture worldwide. One species, Caligus sclerotinosus Roubal, Armitage & Rohde, 1983 (Caligidae), is considered a serious pest of the highly prized red seabream Pagrus major (Temminck and Schlegel, 1843) (Sparidae) cultured in Japan. Recently, in neighboring Korea, red seabream culture has intensified and almost replaced yellow tail culture. However, until now, there have been no reports on infection of this sea louse from red seabream in Korea. We surveyed 120 (20 fish per month) P. major from a sea ranched Tongyeong Marine Research Center aquaculture facility, Gyeongsangnamdo, Korea for six months in 2011 (June to November). We recorded severe infection by the sea louse C. sclerotinosus on the skin of P. major. Prevalence was 100%, mean intensity 7.06, maximum intensity 49, and minimum intensity 2. Adult females (624), males (219) and few chalimi (5) were observed and identified by their morphology. As an average of all our collections, less than 0.6% of individuals were chalimi. We suggest, therefore, that adults of C. sclerotinosus undergo ontogenetic host switching after their final moult. No infection of C. sclerotinosus was found on wild P. major collected from Tongyeong and Yeosu fish markets on the southern coast of Korea. Severe infection by this sea louse may cause secondary infections of the host. This copepod is already reported from Australia and Japan and hence, this is the first report from Korea. We expect this pest to have an impact on Korean red seabream fisheries equally serious to that being experienced in Japan.

Redescription of two Pennellids (Copepoda, Siphonostomatoida) from Korea with a key to species of Peniculus von Nordmann, 1832.

Redescriptions of two pennellid copepods, Peniculus minuticaudae Shiino, 1956 and Peniculus truncatus Shiino, 1956, are provided, based on postmetamorphic adult females collected from marine ranched fishes captured at Tongyeong marine living resources research & conservation center, Korea. Peniculus minuticaudae was collected from the soft fin rays of black scraper Thamnaconus modestus. It can be distinguished from the other two closely related congeners Peniculus ostraciontis Yamaguti, 1939 and Peniculus truncatus by having a well developed triangular-shaped abdomen; the abdomen is rudimentary in other two species. This is thefirst report of the occurrence of Peniculus minuticaudae in Korea. Peniculus truncatus was collected from the dorsal fin of Korean rockfish Sebastes schlegelii. It can be distinguished from Peniculus minuticaudae by the combination of a rudimentary abdomen, long neck and setae on leg 1 and from Peniculus ostraciontis by the long neck, slender trunk, and setae on leg 1. It is also shown that Peniculus truncatus captured from the same host in Korea was misidentified as Peniculus ostraciontis and hence, this is thesecond record of the occurrence of Peniculus truncatus in Korea. A key is provided for the 14 nominal species of Peniculus.