Flying fishes (Beloniformes: Exocoetidae) of the Socotra Archipelago with comments on status of Exocoetus socotranus Steindachner.

A checklist of the flying fishes found in the waters off Socotra Archipelago, northwestern part of the Indian Ocean, is provided based on published and original data. Thirteen species from five genera occur in the study area, and four more species found nearby. Keys for the species identification are provided. The type specimen of Exocoetus socotranus Steindachner, 1902 was examined and is determined to be a junior synonym of Cypselurus naresii (Günther, 1889).

The complete mitochondrial genome of the Pacific needlefish Strongylura anastomella (Belonidae, Beloniformes) from Korea.

Belonidae is a good model for investigating speciation and biogeography. To obtain basic information on the phylogeny of Belonidae, we determined the complete mitogenome of Strongylura anastomella using next-generation sequencing. The complete mitogenome is 16,534 bp in length and consists of 2 rRNAs, 22 tRNAs, 13 protein-coding genes and a control region. The nucleotide composition is 31.1% A, 29.8% T, 14.5% G and 24.6% C, with an AT bias (60.9%). The gene direction and position were similar to those of other Beloniformes. Belonidae and Scomberesocidae were separated in the phylogenetic tree based on complete mitogenomes. Further study is required to clarify the phylogenetic relationships among Belonidae and families within Beloniformes.

Flyingfish feeding ecology in the eastern Pacific: prey partitioning within a speciose epipelagic community.

To test the hypothesis that prey partitioning contributes to community stability in flyingfish, the gut contents of 359 flyingfish specimens (representing five genera and eight species within Exocoetidae and Hemiramphidae) were collected at 50 dip-net stations during hour-long night-time fishing in oceanic waters of the eastern tropical Pacific Ocean between August and November 2007. Analyses using multidimensional scaling, and analysis of similarity revealed significant dietary differences among species, and similarity percentages tests helped identify the specific prey taxa responsible for these differences. Six species specialized on copepods (58·3-96·9% by number), but targeted different families. Specifically, the barbel flyingfish Exocoetus monocirrhus (n = 205) focused on euchaetids (51·6%), the banded flyingfish Hirundichthys marginatus (n = 24) fed on pontellids (21·8%), while the tropical two-wing flyingfish Exocoetus volitans (n = 11) and the bigwing halfbeak Oxyporhamphus micropterus (n = 34) ingested calanoids (54·6 and 17·0%). In contrast, the whitetip flyingfish Cheilopogon xenopterus (n = 73) and the mirrorwing flyingfish Hirundichthys speculiger (n = 4) had generalized diets comprising similar proportions of amphipod, copepod, mollusc and larval fish prey. Distinct differences in mean fullness, highly digested material, per cent empty guts and mean numbers of prey per gut were also synthesized, and uncovered a pattern of asynchronous feeding. Altogether, these findings provide valuable descriptive data on the diets of an understudied group of epipelagic teleosts, and, by extension, suggest that prey partitioning (taxa and feeding times) may influence flyingfish feeding ecology by reducing interspecific competition.

Paleo-drainage basin connectivity predicts evolutionary relationships across three Southeast Asian biodiversity hotspots.

Understanding factors driving diversity across biodiversity hotspots is critical for formulating conservation priorities in the face of ongoing and escalating environmental deterioration. While biodiversity hotspots encompass a small fraction of Earth's land surface, more than half the world's plants and two-thirds of terrestrial vertebrate species are endemic to these hotspots. Tropical Southeast (SE) Asia displays extraordinary species richness, encompassing four biodiversity hotspots, though disentangling multiple potential drivers of species richness is confounded by the region's dynamic geological and climatic history. Here, we use multilocus molecular genetic data from dense multispecies sampling of freshwater fishes across three biodiversity hotspots, to test the effect of Quaternary climate change and resulting drainage rearrangements on aquatic faunal diversification. While Cenozoic geological processes have clearly shaped evolutionary history in SE Asian halfbeak fishes, we show that paleo-drainage re-arrangements resulting from Quaternary climate change played a significant role in the spatiotemporal evolution of lowland aquatic taxa, and provide priorities for conservation efforts.

Molecular phylogeny of the medaka fishes genus Oryzias (Beloniformes: Adrianichthyidae) based on nuclear and mitochondrial DNA sequences.

The phylogenetic relationships among medaka fishes of 2 genera, Oryzias and Xenopoecilus, were studied using the nuclear tyrosinase and mitochondrial 12S and 16S rRNA genes. Of the 23 species currently described for these genera, 13 species of Oryzias and 2 species of Xenopoecilus were examined. The tree topologies obtained from the nuclear and mitochondrial data were consistent, indicating that Xenopoecilus is a polyphyletic genus nested within Oryzias. This result suggested the necessity for a systematic study and taxonomic revision of Xenopoecilus. The combined data analysis of all data partitions resulted in a well-resolved tree, with most internal branches supported by high statistical values. Based on our combined data phylogeny, we divided the Oryzias species into three major species groups, namely the latipes, javanicus, and celebensis groups. These three groups corresponded to the three chromosomal groups (biarmed, monoarmed, and fused chromosome groups) previously proposed from karyological analyses. The phylogeographic pattern suggests historical vicariance between Sulawesi Island and the continental shelf.

A new species of halfbeak, Hyporhamphus naos (Beloniformes: Hemiramphidae), from the tropical eastern Pacific

The tropical eastern Pacific halfbeak previously considered conspecific with the western Atlantic Hyporhamphus unifasciatus (Ranzani 1842) is described as a new species, H. naos. It resembles H. meeki from the Atlantic and Gulf coasts of the United States in number of gill rakers on the first arch (usually 32-36, mean 33.6), more than in H. unifasciatus (usually 29-32, mean 30.6), but fewer than in other sympatric species of eastern Pacific Hyporhamphus. Results of a three-treatment ANCOVA (H. naos, H. meeki, and H. unifasciatus) show significant differences in slopes and means for all 14 morphometric characters examined, 9 of 14 characters comparing H. naos with H. unifasciatus, and 7 of 14 comparing H. naos with H. meeki. Protein electrophoretic patterns clearly distinguish all three species with a number of fixed allelic differences.

Status of the eastern Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876) (Beloniformes: Belonidae)

Tylosurus pacificus (Steindachner, 1876) is confirmed to have full species rank based on: 1) sympatry with T. acus melanotus at Isla Gorgona and in Panamá; 2) level of morphological differentiation in numbers of vertebrae, dorsal and anal fin rays; and 3) level of mtDNA differentiation. The eastern Pacific agujon needlefish is found from the Gulf of California, Mexico, to Peru, including the Galápagos Islands.

A new species of halfbeak, Hyporhamphus naos (Beloniformes: Hemiramphidae), from the tropical eastern Pacific.

The tropical eastern Pacific halfbeak previously considered conspecific with the western Atlantic Hyporhamphus unifasciatus (Ranzani 1842) is described as a new species, H. naos. It resembles H. meeki from the Atlantic and Gulf coasts of the United States in number of gill rakers on the first arch (usually 32-36, mean 33.6), more than in H. unifasciatus (usually 29-32, mean 30.6), but fewer than in other sympatric species of eastern Pacific Hyporhamphus. Results of a three-treatment ANCOVA (H. naos, H. meeki, and H. unifasciatus) show significant differences in slopes and means for all 14 morphometric characters examined, 9 of 14 characters comparing H. naos with H. unifasciatus, and 7 of 14 comparing H. naos with H. meeki. Protein electrophoretic patterns clearly distinguish all three species with a number of fixed allelic differences.

Status of the eastern Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876) (Beloniformes: Belonidae).

Tylosurus pacificus (Steindachner, 1876) is confirmed to have full species rank based on: 1) sympatry with T. acus melanotus at Isla Gorgona and in Panamá; 2) level of morphological differentiation in numbers of vertebrae, dorsal and anal fin rays; and 3) level of mtDNA differentiation. The eastern Pacific agujon needlefish is found from the Gulf of California, Mexico, to Peru, including the Galápagos Islands.