Acanthopagrus oconnorae, a new species of seabream (Sparidae) from the Red Sea.

A new species of sparid fish, Acanthopagrus oconnorae, is described based on 11 specimens collected in the shallow (0-1 m depth) mangrove-adjacent sandflats of Thuwal, Saudi Arabia. The new species is distinguished from its congeners by the following combination of characters: second anal-fin spine 12.8%-16.6% of standard length (SL); 3½ scale rows between the fifth dorsal-fin spine and lateral line; suborbital width 5.7%-6.7% of SL; eyes positioned at the anterior edge of the head, often forming a weakly convex break in an otherwise gently curved head profile, when viewed laterally; caudal fin light yellow with black posterior margin (approximately half of fin); anal fin dusky grey, with posterior one-fifth of the fin light yellow; black streaks on inter-radial membranes of anal fin absent. The most similar species to A. oconnorae is Acanthopagrus vagus, which differs by the presence of a w-shaped anterior edge of the scaled predorsal area, a more acute snout and black streaks on the inter-radial membranes of the anal fin. Phylogenetic placement and species delimitation of A. oconnorae are discussed based on COI, CytB and 16S sequences. It is hypothesized that ecology and behaviour explain how this species avoided detection despite its likely occurrence in coastal areas of the Red Sea with historically high fishing pressure.

Pristipomoides amoenus (Snyder 1911), a valid species of jobfish (Pisces, Lutjanidae), with comparisons to P. argyrogrammicus (Valenciennes 1832).

Platyinius amoenus Snyder 1911 has long been considered a junior synonym of Pristipomoides argyrogrammicus (Valenciennes 1832), however, the two are discernible as distinct species from color patterns and counts of gill rakers based on examination of their type materials and non-type specimens. Furthermore, genetic differences based on molecular analysis among the two species (mtDNA, COI gene) strongly support the validity of both species. Pristipomoides amoenus can be readily distinguished from P. argyrogrammicus in having no white margin to the dorsal, anal, and caudal fins, silvery blue spots continuing inside dorso-lateral yellow blotches, and presence of modally10 (vs. modally 12) lower gill rakers. Both species were collected sympatrically around Ishigaki Island, Okinawa, Japan.

Acanthopagrus datnia (Hamilton, 1822), a senior synonym of Acanthopagrus longispinnis (Valenciennes, 1830) (Perciformes: Sparidae).

The taxonomic status of the Bay of Bengal nominal sparid species Coius datnia Hamilton, 1822 and Acanthopagrus longispinnis (Valenciennes, 1830) are reviewed and investigated both morphologically and genetically. Because of inadequate description and no type specimen, Coius datnia has recently been considered to belong to Sparidentex, a genus without molarifom teeth. Critical examination of the original description and examination of specimens from the type locality and adjacent areas reveal that Coius datnia belongs to Acanthopagrus, a genus with an inner series of molars. Furthermore, examination of specimens previously recognized as Acanthopagrus longispinnis (Valenciennes 1830), and recent collection of fresh specimens from lower Ganges estuary in Bangladesh, show that morphological differences between Acanthopagrus datnia and A. longispinnis are minor, and they are genetically identical. The longer second anal-fin spine in A. longispinnis (>21% SL) is, in fact, a feature of some younger A. datnia. Accordingly, A. datnia is regarded as a senior synonym of A. longispinnis, and is distinguished from its congeners by the presence of 12 dorsal-fin spines (rarely 11 or 13), 3½ scale rows between the fifth dorsal-fin spine base and lateral line, pelvic and anal-fins pale yellow to yellow with black streaks present in the interradial membranes of anal-fin rays, and caudal fin grey or yellowish grey. A neotype (and neogenotype) has been designated for Acanthopagrus datnia (Hamilton, 1822).

Morphological and genetic evaluation of the thumbprint emperor, Lethrinus harak (Forsskål, 1775) in the Pacific and Indian Oceans.

Background: The Lethrinidae (emperors) include many important food fish species. Accurate determination of species and stocks is important for fisheries management. The taxonomy of the genus Lethrinus is problematic, for example with regards to the identification of the thumbprint emperor Lethrinus harak. Little research has been done on L. harak diversity in the Pacific and Indian Oceans. This study aimed to evaluate the morphometric and genetic characters of the thumbprint emperor, L. harak (Forsskål, 1775) in the Pacific and Indian Oceans. Methods: This research was conducted in the Marine Biology Laboratory, Faculty of Marine Science and Fisheries, Hasanuddin University, and Division of Fisheries Science, University of Miyazaki. Morphometric character measurements were based on holotype character data, while genetic analysis was performed on cytochrome oxidase subunit I (COI) sequence data. Morphometric data were analysed using principal component analysis (PCA) statistical tests in MINITAB, and genetic data were analysed in MEGA 6. Results: Statistical test results based on morphometric characters revealed groupings largely representative of the Indian and Pacific Oceans. The Seychelles was separated from other Indian Ocean sites and Australian populations were closer to the Pacific than the Indian Ocean group. The genetic distance between the groups was in the low category (0.000 - 0.042). The phylogenetic topology reconstruction accorded well with the morphometric character analysis, with two main L. harak clades representing Indian and Pacific Ocean, and Australia in the Pacific Ocean clade. Conclusions: These results indicate that geographical and environmental factors can affect the morphometric and genetic characteristics of L. harak.

Taxonomic review of the genus Argyrops (Perciformes; Sparidae) with three new species from the Indo-West Pacific.

The Indo-West Pacific sparid genus Argyrops is reviewed, with four valid species and three new species: A. bleekeri Oshi-ma, 1927, A. filamentosus (Valenciennes, 1830), A. megalommatus (Klunzinger, 1870), A. spinifer (Forsskål, 1775), A. caeruleops n. sp., A. flavops n. sp. and A. notialis n. sp. The above seven species can be differentiated on meristic values, ontogenetic and morphological characters, and coloration. Argyrops bleekeri from the western Pacific and A. notialis n. sp. from Western Australia both have only one rudimentary dorsal-fin spine on the first dorsal pterygiophore (which defines the Argyrops bleekeri complex), while the five other congeners have two rudimentary dorsal-fin spines, both associated with the first dorsal pterygiophore. Argyrops filamentosus, A. megalommatus, and A. caeruleops n. sp. have the 3rd dorsal-fin spine filamentous and longest, the defining character of the A. filamentosus complex. Argyrops spinifer (from the Indian Ocean) and A. flavops n. sp. (from the Middle East to Pakistan, but not the Red Sea and probably rare in the Persian Gulf) differ from other complexes in having 4-6 elongated or filamentous dorsal-fin spines (usually 3rd-6th [four spines] or 3rd-8th [six spines]) in juveniles and subadults, with the first 2 dorsal-fin spines rudimentary, the characteristic of the A. spinifer complex. The above three complexes include the seven Argyrops species that are defined and supported by morphological and color differences, genetic distinctions (partial cytochrome b genes, 1,116 bp), and distribution. The nominal species are discussed, together with several geographic variations of A. spinifer from the Indian Ocean, and a key to the species is provided.

Validity of Psammoperca datnioides Richardson 1848 and redescriptions of P. waigiensis Cuvier in Cuvier Valenciennes 1828 and Hypopterus macropterus (Günther 1859) in the family Latidae (Perciformes) from the Indo-West Pacific.

Psammoperca datnioides Richardson 1848, long considered a synonym of P. waigiensis (Cuvier in Cuvier Valenciennes 1828), is redescribed as a valid species of Psammoperca Richardson 1848. The species is likely to be endemic to Australia, where it was formerly considered to be P. waigiensis, but differs from P. waigiensis in having the following characters: more slender body (mean depth 28.9% of SL vs. mean depth 36.7% of SL in P.  waigiensis), pored lateral-line scales 49-54 (vs. 46-48 in P. waigiensis), scale rows above and below lateral line 6½ / 10½-11½ (vs 4½ / 9½-10½ in P. waigiensis), and vertical at hind margin of maxilla posterior/behind center of eye (vs. vertical at hind margin of maxilla anterior to/in front of hind margin of eye in P. waigiensis). Live specimens of Psammoperca datnioides have a uniformly dense black or brownish body, with this dark colour on body scales and pored lateral-line scales persisting even in preserved specimens. Live specimens of Psammoperca waigiensis have a brownish body, often golden in colour, and pored lateral-line scales that are yellow-edged. The COI sequence (cytochrome c oxidase subunit I, 612 bp) of P. datnioides also is distinct from P. waigiensis, and the related and poorly known Hypopterus macropterus (Günther 1859). The latter species is redescribed and diagnosed with eight indistinct dark bands on the head and body, and dorsal-fin rays VII-I, 14-15 (vs. no dark bands and dorsal-fin rays VII-I, 12-13 in Psammoperca). Nominal species in the genus Psammoperca are discussed and Cnidon chinensis Müller Troschel 1849 (type locality: Manila, Philippines) is included as a junior synonym of P. waigiensis. Psammoperca vaigiensis Boulenger 1895 is an unneeded emendation and thus an invalid name. Psammoperca macroptera Günther 1859 is retained in the monotypic genus Hypopterus Gill 1861 in the family Latidae, although the species has been overlooked in most studies on the Latidae and/or Centropomidae. A key to the Latidae is provided.

Validity of a blue stripe snapper, Lutjanus octolineatus (Cuvier 1828) and a related species, L. bengalensis (Bloch 1790) with a new species (Pisces; Lutjanidae) from the Arabian Sea.

Lutjanus octolineatus (Cuvier 1828), previously considered a junior synonym of Lutjanus bengalensis (Bloch 1790), is shown to be a valid species and lectotypes are designated. Both species are redescribed. The two species have overlapping distributions in the Indian Ocean, but are clearly separable by different dorsal-fin spine counts, blue-striped pattern on the body and the presence or absence of a subocular extension of cheek scales. Lutjanus octovittata (Valenciennes 1830), formerly assigned to synonymy of L. bengalensis, is considered a junior synonym of L. octolineatus based on examination of the holotype. Lutjanus sapphirolineatus n. sp., a species formerly misidentified as L. bengalensis, is described based on 10 specimens from Oman and Somalia. The new species differs from the three species above by a combination of different characters. Analysis of the mitochondrial cytochrome c oxidase subunit 1 (CO1, 603 bp) genetic marker, also strongly supports the validity of each species of the blue-striped snapper complex as distinct.

Amamiichthys, a new genus for the sparid fish Cheimerius matsubarai Akazaki 1962, and redescription of the species, with designation of a neotype.

A new genus, Amamiichthys, is proposed for the sparid fish Cheimerius matsubarai Akazaki 1962. This genus differs from all other genera in the family Sparidae by the following combination of characters: both jaws with an outer row of small molariform teeth and an inner row of similar, even smaller teeth; frontal bone flat, coarse and porous; strongly bifurcate protuberance of upper ethmoid just beneath mid-region of anteriormost portion of frontal bone; head and body pinkish, gradually becoming silvery toward abdomen, with many small blue spots, some pairs overlapping. The type species, Amamiichthys matsubarai, is redescribed and a neotype designated.

Redescriptions of Polysteganus coeruleopunctatus (Klunzinger 1870) and P. lineopunctatus (Boulenger 1903), with two new species from Western Indian Ocean.

Five valid species in the genus Polysteganus (Pisces; Sparidae) from the Western Indian Ocean are currently known: P. baissaci Smith 1978, P. coeruleopunctatus (Klunzinger 1870), P. mascarenensis Iwatsuki & Heemstra, 2011, P. praeorbitalis (Günther 1859), and P. undulosus (Regan 1908). Although P. lineopunctatus (Boulenger 1903) has long been synonymized under P. coeruleopunctatus, both species are redescribed as valid. Two new species of Polysteganus were discovered in the course of this review. Polysteganus flavodorsalis n. sp. is described on the basis of six type specimens (143-265 mm SL) from Nazareth Bank, Mascarene Plateau, Indian Ocean, and P. cerasinus n. sp. is described based on the holotype (134 mm SL) from Saya de Malha Bank. Provisional distribution patterns of the eight valid species of Polysteganus in the Western Indian Ocean are discussed. A key to the species of Polysteganus is provided.

Dentex carpenteri, a new species of deepwater seabream from Western Australia (Pisces: Sparidae).

A new species of sparid fish, Dentex carpenteri, is described from nine type specimens collected off Ningaloo Reef near Exmouth, Western Australia. Four valid species of Dentex are currently known in the western Pacific, Dentex abei and D. hypselosomus in the Northern Hemisphere, and D. fourmanoiri and D. spariformis in the Southern Hemisphere. These four species comprise the "Dentex hypselosomus complex". Dentex carpenteri n. sp. is most similar to D. spariformis in overall body form, but differs from D. spariformis in having the posterior margin of the upper jaw not reaching or reaching slightly beyond a vertical at the anterior margin of eye; often with the greater part from the snout to the second infraorbital yellowish; deeper suborbital (9.7-10.9% SL); and a considerably deeper body (vs. posterior margin of upper jaw reaching clearly beyond anterior margin of eye; slight yellow region on snout; suborbital depth shallow (7.6-9.6% SL); and a less deep body in D. spariformis). The mitochondrial 16S ribosomal RNA genes (16S rRNA, 545 bp) of the above five species were analyzed using the Atlantic congener, Dentex macrophthalmus as an out-group, the results clearly indicating that D. carpenteri n. sp. is a valid and distinct species. A key to the "Dentex hypselosomus complex" is provided. The distributional information available for the five species from the western Pacific, including western Australia and the nearby eastern Indian Ocean, are discussed, with the species considered to be allopatric.

Limited geographic distribution of certain strains of the bioluminescent symbiont Photobacterium leiognathi.

Photobacterium leiognathi is a facultative bioluminescent symbiont of marine animals. Strains of P. leiognathi that are merodiploid for the luminescence genes (lux-rib operon) have been previously obtained only from Japan. In contrast, strains bearing a single lux-rib operon have been obtained from all the areas sampled in Japan and the western Pacific. In this study, we tested whether distribution of merodiploid P. leiognathi is limited by physical barriers in the environment, or because fish in the western Pacific preferentially form symbiosis with bacteria bearing a single lux-rib operon. We collected light organ symbionts from Secutor indicius, a fish species that is typically found in the western Pacific and has only recently expanded its geographic range to Japan. We found that all S. indicius specimens collected from Japan formed symbiosis only with single lux-rib operon-bearing strains, although fish from other species collected from the same geographic area frequently contained merodiploid strains. This result shows that S. indicius were preferentially colonized by bacteria bearing a single lux-rib operon and suggests that the limited geographic distribution of merodiploid P. leiognathi can be attributed to preferential colonization of fish species found in the western Pacific by strains bearing only a single lux-rib operon.

Comprehensive phylogeny of the family Sparidae (Perciformes: Teleostei) inferred from mitochondrial gene analyses.

Sparid fishes consist of approximately 115 species in 33 genera that are broadly distributed in tropical and temperate coastal waters. Although several phylogenetic analyses were conducted based on specific molecular markers, their classification remains unresolved. Here, we present the most comprehensive molecular phylogeny of the family Sparidae to date, based on cytochrome b (cyt-b) genes. We determined 18 sequences of sparids and conducted phylogenetic analyses among 72 individuals representing 66 sparids with 23 outgroup species. Phylogenetic trees were constructed according to partitioned Maximum Likelihood (ML) and Bayesian methods. The phylogenetic analyses were conducted on two different data sets (including all positions; RY-coding). The phylogenetic trees showed monophyly of the family Sparidae with a different taxon, centracanthid Spicara. The subfamilies in the Sparidae in all trees are non-monophyletic and do not agree with current classification of the subfamilies. The genera Acanthopagrus, Cheimerius, Dentex, Diplodus, Pagellus, Pagrus, and Spicara are also non-monophyletic and their classifications should be revised based on the phylogenetic relationships and reinvestigation of morphological characters. The sparids are divided into three major clades, A, B and C, respectively in the ML tree based on all codon positions, whereas clade C was paraphyletic in the other trees. The species in clade C are known to be present in the eastern Pacific to western Atlantic, whereas those in clades A and B are distributed in various oceanic regions. Some sub-clades in clades A and B consist of species that are distributed in defined local regions. We further investigated evolutionary patterns of 87 morphological characters by ancestral character-state reconstruction according to the parsimony criteria. The results suggested high evolutionary plasticity of the characters in sparids, indicating that it causes species-diversity and taxonomic confusion at various taxonomic levels, and that such convergent evolution may occur more frequently also in other coastal fishes.

Molecular identification of hairtail species (Pisces: Trichiuridae) based on PCR-RFLP analysis of the mitochondrial 16S rRNA gene.

A rapid PCR-RFLP analysis was designed to identify 3 closely related species of hairtails: Trichiurus lepturus, T. japonicus, and Trichiurus sp. 2, basing on partial sequence data (600 bp) of the mitochondrial DNA encoding the 16S ribosomal RNA (16S rRNA) gene. Restriction digestion analysis of the unpurified PCR products of these 3 species, using EcoRI and VspI endonucleases, generated reproducible species-specific restriction patterns showing 2 fragments (250 bp and 350 bp) for T. lepturus in EcoRI digestion and 2 fragments (196 bp and 404 bp) for T. japonicus in VspI digestion, whereas no cleavage was observed for Trichiurus sp. 2 in both EcoRI and VspI digestions. The PCR-RFLP technique developed in this study proved to be a rapid, reliable and simple method that enables easy and accurate identification of these 3 closely related species of the genus Trichiurus.