Luteirhabdus pelagi gen. nov., sp. nov., a novel member of the family Flavobacteriaceae, isolated from the West Pacific Ocean

A Gram-stain-negative, aerobic, and yellow-pigmented bacterium, designated A3-108T, was isolated from seawater of the West Pacific Ocean. Cells were non-motile and rod-shaped, with carotenoid-type pigments. Strain A3-108T grew at pH 6.0–8.5 (optimum 6.5) and 15–40 °C (optimum 28 °C), in the presence of 0.5–10% (w/v) NaCl (optimum 1.0%). It possessed the ability to produce H2S. Based on the 16S rRNA gene analysis, strain A3-108T exhibited highest similarity with Aureisphaera salina A6D-50T (90.6%). Phylogenetic analysis shown that strain A3-108T affiliated with members of the family Flavobacteriaceae and represented an independent lineage. The principal fatty acids were iso-C15:0, iso-C17:0 3-OH, iso-C15:1 G, and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The sole isoprenoid quinone was MK-6. The major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified aminolipid and one unidentified lipid. The ANIb, in silico DDH and AAI values among the genomes of strain A3-108T and three reference strains were 67.3–71.1%, 18.7–22.1%, and 58.8–71.4%, respectively. The G + C content was 41.0%. Distinctness of the phylogenetic position as well as differentiating chemotaxonomic and other phenotypic traits revealed that strain A3-108T represented a novel genus and species of the family Flavobacteriaceae, for which the name Luteirhabdus pelagi gen. nov., sp. nov. is proposed (type strain, A3-108T = CGMCC 1.18821T = KCTC 82563T).

Tabwecala robinsoni gen. nov., sp. nov., from Vanuatu and its systematic position in the ‘Ophiusini-Poaphilini’ clade (Lepidoptera, Erebidae)

A new erebid, Tabwecala robinsonigen. nov., sp. nov., from the Vanuatu Islands (Espiritu Santo) (West Pacific Ocean) is described. The new species, superficially resembling species of the genera Artena, Achaea or Leistera, shows a peculiar combination of characters which suggested its placement in a new genus. This is provisionally placed in tribe Poaphilini but following a review of the features purporting to show the separation of Ophiusini and Poaphilini, it is shown that morphological rationale supporting the current arrangement of these tribes is still lacking. Noteworthy modifications affect the hindleg of male Tabwecala robinsoni, with greatly shortened and swollen metatibia bearing a dorsal hair-pencil.

Unraveling cryptic diversity among shallow-water tonguefishes (Pleuronectiformes: Cynoglossidae: Symphurus) from the Indo-West Pacific region, with descriptions of five new species

Species of Symphurus (Pleuronectiformes: Cynoglossidae) are relatively small-sized tonguefishes occurring worldwide in tropical, subtropical, and warm-temperate seas. In the Indo-West Pacific Ocean, species of Symphurus inhabiting waters shallower than 200 m are rarely reported; only five have been described, S. microrhynchus (Weber, 1913), S. holothuriae Chabanaud, 1948, S. monostigmus Munroe, 2006, S. leucochilus Lee et al. 2014, and S. longirostris Lee et al. 2016. Examination of museum and recently collected specimens yielded over 100+ Symphurus captured in relatively shallow waters off Japan, Papua New Guinea, the Philippines, Taiwan, and Vietnam. All of these specimens, except S. monostigmus (with 14 caudal-fin rays), were originally tentatively identified as S. microrhynchus because of shared similarities (small size, low meristic values, 12 caudal-fin rays, shared pigmentation traits). Detailed comparisons revealed that, although similar, specimens from allopatric locations have small differences in meristic, morphometric and pigmentation features. In previous literature, these small differences were thought to represent intraspecific variation among populations of a widespread species, S. microrhynchus. However, further study, including molecular data, has revealed that such minor differences among specimens from allopatric locations actually represent interspecific, and not population-level, variations. Where available, molecular differences among these allopatric populations, in contrast to the morphological features, were significantly different (9.0 to 26.3%), providing additional strong support for the hypothesis that more than one species is represented among fishes examined. Combined data from morphological and molecular characters, and species delimitation analysis, reveal that five, undescribed, cryptic species should be recognized: S. brachycephalus n. sp. from Vietnam, S. hongae n. sp. from Taiwan, S. leptosomus n. sp. from the Philippines, S. polylepis n. sp. from Papua New Guinea, and S. robustus n. sp. from Japan. Also, based on new information, the previous decision to place S. holothuriae Chabanaud in the synonymy of S. microrhynchus was determined to be premature. This species should be recognized as valid until additional specimens are captured and the taxonomic status of this nominal species re-evaluated. At least 10 species of Indo-West Pacific shallow-water Symphurus are now known. Eight are members of the Symphurus microrhynchus species complex with hypothesized closer relationship to each other than to the other two species of shallow-water tonguefishes. Included in this study are redescriptions of S. microrhynchus and S. holothuriae based on their holotypes, including an expanded number of morphological characters not previously used to diagnose these species; redescriptions are also provided for comparative purposes of three other shallow-water species; five new cryptic species are described; and lastly, detailed comparisons and an identification key to all 10 species of shallow-water Symphurus occurring in the Indo-West Pacific Ocean are provided. Two additional populations are also identified that likely represent other undescribed taxa belonging to the S. microrhynchus species complex. Adequate specimens are not available at this time to formally describe these nominal species. This study contributes further understanding about species diversity within Symphurus inhabiting shallow waters of the Indo-West Pacific Ocean. Several other nominal species of small-sized cynoglossid and soleid flatfishes are currently considered to have widespread distributions in the Indo-West Pacific. Many of these species also have junior synonyms available based on nominal species described from allopatric sites within their geographic ranges. How many of these presumed populations of widespread species will be resurrected from synonymy once additional specimens and their genetic information becomes available remains an interesting question for future study.

Gold in Ferromanganese Deposits from the NW Pacific

Ferromanganese crusts from four different areas of the North-West Pacific Ocean—the Detroit (northern part of the Imperial Ridge) guyot, the Zubov (Marshall Islands) guyot, the “Gummi Bear” seamount (an intraplate volcano near the Krusenstern FZ), and Belyaevsky volcano (the Sea of Japan)—were studied. Samples from the Detroit and Zubov guyots and the “Gummi Bear” seamount have similar chemical and mineral compositions of hydrogenetic cobalt-rich ferromanganese crusts. Crust from the Sea of Japan seems to reflect a hydrothermal influence. The gold content in most samples from the Detroit guyot was 68 ppb and from the Zubov guyot varied from 180 to 1390 ppb, which is higher than the average for the Pacific crusts (55 ppb). Gold content in two other samples was less than 10 ppb. Based on the electron microscopic studies, aggregation of gold particles with a size of 680 μm were identified in the Detroit guyot crust. The sizes of the Au particles are up to 10–15 μm, which has not been previously noted. Gold particles similar in morphology and size were also found in the Zubov guyot crust, which is located far from the Detroit guyot. The largest particle of gold (≈60 μm), represented by electrum, was found in the clay substrate from the “Gummi Bear” seamount. The lamellar, rudaceous morphology of the gold particles from the Detroit and Zubov guyots reflects their in situ formation, in contrast to the agglutinated, rounded with traces of dragging gold grain found in the substrate of the sample from the “Gummi Bear” seamount. Three-component (Ag-Au-Cu) gold particles were found in the hydrothermal crust from the Belyaevsky underwater volcano. Grains similar in composition were also found in Co-rich crust. The research results show that the gold was probably added to by hydrothermal fluid in the already-formed hydrogenetic ferromanganese crusts during rejuvenated volcanic stages. Biogeochemical processes may have played a major role in the formation of submicron solid-phase gold particles.

A functional analysis reveals extremely low redundancy in global mangrove invertebrate fauna

Deforestation results in habitat fragmentation, decreasing diversity, and functional degradation. For mangroves, no data are available on the impact of deforestation on the diversity and functionality of the specialized invertebrate fauna, critical for their functioning. We compiled a global dataset of mangrove invertebrate fauna comprising 364 species from 16 locations, classified into 64 functional entities (FEs). For each location, we calculated taxonomic distinctness (Δ+), functional richness (FRi), functional redundancy (FRe), and functional vulnerability (FVu) to assess functional integrity. Δ+ and FRi were significantly related to air temperature but not to geomorphic characteristics, mirroring the global biodiversity anomaly of mangrove trees. Neither of those two indices was linked to forest area, but both sharply decreased in human-impacted mangroves. About 60% of the locations showed an average FRe < 2, indicating that most of the FEs comprised one species only. Notable exceptions were the Eastern Indian Ocean and west Pacific Ocean locations, but also in this region, 57% of the FEs had no redundancy, placing mangroves among the most vulnerable ecosystems on the planet. Our study shows that despite low redundancy, even small mangrove patches host truly multifunctional faunal assemblages, ultimately underpinning their services. However, our analyses also suggest that even a modest local loss of invertebrate diversity could have significant negative consequences for many mangroves and cascading effects for adjacent ecosystems. This pattern of faunal-mediated ecosystem functionality is crucial for assessing the vulnerability of mangrove forests to anthropogenic impact and provides an approach to planning their effective conservation and restoration.

Luteorhabdos pelagi gen. nov., sp. nov., a novel member of the family Flavobacteriaceae, isolated from the West Pacific Ocean

Gram-stain-negative, aerobic and yellow-pigmented bacterium, designated A3-108T, was isolated from seawater of the West Pacific Ocean. Cells were non-motile and rod-shaped, with carotenoid-type pigments. The strain A3-108T grew at pH 6.0-8.5 (optimum 6.5) and 15–40℃ (optimum 28℃), in the presence of 0.5–10% (w/v) NaCl (optimum 1.0%). It possessed the ability to produce H2S. Based on the 16S rRNA gene analysis, strain A3-108T exhibited highest similarity with Aureisphaera salina A6D-50T (90.6%). Phylogenetic analysis shown that strain A3-108T affiliated with the family Flavobacteriaceae and represented an independent lineage. The principal fatty acids were iso-C15:0, iso-C17:0 3-OH, iso-C15:1 G and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The sole isoprenoid quinone was MK-6. The major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified aminolipid and one unidentified lipid. The ANIb, in silico DDH and AAI values among the genomes of strain A3-108T and the reference strains were 67.3–71.1%, 18.7–22.1% and 58.8–71.4%, respectively. The G + C content was 41.0%. Differential phylogenetic distinctiveness, chemotaxonomic differences as well as phenotypic properties revealed that strain A3-108T represented a novel genus and species of the family Flavobacteriaceae, for which the name Luteorhabdos pelagi gen. nov., sp. nov. is proposed (type strain, A3-108T = CGMCC 1.18821T = KCTC 82563T).