Description of a new deep-water species of Heteroclinus (Pisces: Teleostei: Clinidae), from southern Australia

Heteroclinus argyrospilos, n. sp. is described as a new species from specimens sampled by sled and dredge in 55–100 m off South Australia and Western Australia. The species has a strongly compressed body and spatulate orbital tentacle similar to some shallow water species, particularly those of the Heteroclinus heptaeolus complex, which is characterized by having three segmented dorsal-fin rays, with the last two rays widely separate from the first ray. It is distinct from other Australian clinids in having two segmented dorsal-fin rays, well separated from the last dorsal-fin spine and a reduced lateral line on the body. It is known from a greater depth than other members of the genus.

Mesophotic Gorgonian Corals Evolved Multiple Times and Faster Than Deep and Shallow Lineages

Mesophotic Coral Ecosystems (MCEs) develop on a unique environment, where abrupt environmental changes take place. Using a time-calibrated molecular phylogeny (mtDNA: mtMutS), we examined the lineage membership of mesophotic gorgonian corals (Octocorallia: Cnidaria) in comparison to shallow and deep-sea lineages of the wider Caribbean-Gulf of Mexico and the Tropical Eastern Pacific. Our results show mesophotic gorgonians originating multiple times from old deep-sea octocoral lineages, whereas shallow-water species comprise younger lineages. The mesophotic gorgonian fauna in the studied areas is related to their zooxanthellate shallow-water counterparts in only two clades (Gorgoniidae and Plexauridae), where the bathymetrical gradient could serve as a driver of diversification. Interestingly, mesophotic clades have diversified faster than either shallow or deep clades. One of this groups with fast diversification is the family Ellisellidae, a major component of the mesophotic gorgonian coral assemblage worldwide.

REPRESENTATIVES OF SOME DIAGNOSTIC AGGLUTINATED FORAMINIFERAL GENERA OF THE SUBCLASS MONOTHALAMANA (BATHYSIPHON, ORBULINELLOIDES, REPMANINA, MILIAMMINA, AGGLUTINELLA, DENTOSTOMENIA, AMMOMASSILINA, PSAMMOLINGULINA) IN THE TETHYS

The present study deals with the paleontology, stratigraphy, paleogeography and paleoenvironment of the sixteen representatives of the Paleogene agglutinated benthic foraminifer Monothalamana of eight genera: Bathysiphon Sars, Orbulinelloides Saidova, Repmanina Suleymanov, Miliammina Heron-Allen & Earland, Agglutinella El-Nakhal, Dentostomina Cushman, Ammomassilina Cushman, Psammolingulina Silvestri. One species Orbulinelloides kaminskii is believed here to be new. As a whole these faunae are rarely described in the micropaleontological literatures, that’s why this study is detected. The recorded species are distributed on both sides of the Northern Tethys (Hungary, France), Southern Tethys (Egypt, UAE, Pakistan), Pacific and Atlantic Ocean. It seems that the changes in paleoceanographic conditions should accentuate the benthic faunal changes. Some of the recorded species are mostly confined to that mention localities in the Atlantic and Pacific Ocean, Northern and Southern Tethys, and it was recorded by a few authors. The deeper water species have smooth tests, while the shallow water specimens are coarser grained. The number differences of the recorded species between the different localities in the Tethys may be due to one or more parameters: the deficiency of available literatures, differences in ecological or environmental conditions (depth, salinity, water temperature, dissolved oxygen, nutrient, land barrier) and not homogeneity in the generic or species concept according to different authors.

New shallow water species of Caribbean Ircinia Nardo, 1833 (Porifera: Irciniidae)

Seven Ircinia morphospecies were collected from three sites in the Caribbean (Bocas del Toro, Panama; the Mesoamerican Barrier Reef, Belize; and the Florida Keys, United States of America). Previous research used an integrative taxonomic framework (genome-wide SNP sampling and microbiome profiling) to delimit species boundaries among these Ircinia. Here, we present morphological descriptions for these species, six of which are new to science (Ircinia lowi sp. nov., Ircinia bocatorensis sp. nov., Ircinia radix sp. nov., Ircinia laeviconulosa sp. nov., Ircinia vansoesti sp. nov., Ircinia ruetzleri sp. nov.) in addition to one species conferre (Ircinia cf. reteplana Topsent, 1923).

Description of a new species of Nannopus Brady, 1880 (Copepoda: Harpacticoida: Nannopodidae) from Argentinean waters, including an updated key to species

Both sexes of a new brackish-water species, Nannopus sinusalbi sp. nov. (Nannopodidae) are described from the Bahía Blanca estuary (38°53’S, 62°07’W) in Buenos Aires Province, Argentina. The only previous record of the genus in the study area was identified as the type species, Nannopus palustris Brady, 1880, with no description or illustrations, hence its authenticity cannot be confirmed. Nannopus brasiliensis Jakobi, 1956 is relegated to species inquirenda in the genus rather than being considered a junior synonym of the type species. Nomenclatural issues related to the usage of the alternative spellings Iliophilus Lilljeborg, 1902 and Ilyophilus sensu Sars (1909) and the unavailability of Ilyophilus canui Kim, Choi & Yoon, 2017 are discussed. An updated key to the 18 identifiable species of Nannopus (excluding the type species N. palustris) is presented. The harpacticoid assemblage at the type locality showed a distinct seasonality with N. sinusalbi sp. nov. representing about 8% of the community. The new species showed densities below 5 ind.cm‑2 during most of the year, reaching an abrupt peak of 40.17 ind.cm‑2 towards the end of the summer, when the maximum proportion of ovigerous females was recorded.

Environmental matching reveals non-uniform range-shift patterns in benthic marine Crustacea

Empirical and theoretical studies suggest that marine species respond to ocean warming by shifting ranges poleward and/or into deeper depths. However, future distributional patterns of deep-sea organisms, which comprise the largest ecosystem of Earth, remain poorly known. We explore potential horizontal range shifts of benthic shallow-water and deep-sea Crustacea due to climatic changes within the remainder of the century, and discuss the results in light of species-specific traits related to invasiveness. Using a maximum entropy approach, we estimated the direction and magnitude of distributional shifts for 94 species belonging to 12 orders of benthic marine crustaceans, projected to the years 2050 and 2100. Distance, direction, and species richness shifts between climate zones were estimated conservatively, by considering only areas suitable, non-extrapolative, and adjacent to the currently known distributions. Our hypothesis is that species will present poleward range-shifts, based on results of previous studies. Results reveal idiosyncratic and species-specific responses, with prevailing poleward shifts and a decline of species richness at mid-latitudes, while more frequent shifts between temperate to polar regions were recovered. Shallow-water species are expected to shift longer distances than deep-sea species. Net gain of suitability is slightly higher than the net loss for shallow-water species, while for deep-sea species, the net loss is higher than the gain in all scenarios. Our estimates can be viewed as a set of hypotheses for future analytical and empirical studies, and will be useful in planning and executing strategic interventions and developing conservation strategies.

Oxythermal habitat as a primary driver of ecological niche and genetic diversity in cisco (Coregonus artedi)

Cisco (Coregonus artedi) are threatened by climate change and lake eutrophication, and their oxythermal habitat can be assessed with TDO3, the water temperature at which dissolved oxygen equals 3 mg L-1. We assessed the influence of TDO3 on cisco habitat use, genetic diversity, diets, and isotopic niche in 32 lakes ranging from oligotrophic to eutrophic. Results showed that as TDO3 increased cisco were captured higher in the water column, in a narrower band, with higher minimum temperatures and lower minimum dissolved oxygen. TDO3 was also negatively related to cisco allelic richness and expected heterozygosity, likely driven by summer kill events. Moreover, TDO3 influenced the isotopic niche of cisco, as fish captured deeper were more depleted in δ13C and more enriched in δ15N compared to epilimnetic baselines. Lastly, cisco in high TDO3 lakes consumed more Daphnia, had fewer empty stomachs, and achieved larger body size. Our work identifies specific characteristics of cisco populations that respond to climate change and eutrophication effects, and provides a framework for understanding responses of other cold-water species at the global scale.

Caller ID for Risso's and Pacific White-Sided Dolphins

Climate change affects the distributions of marine mammals1, and some temperate water species are spreading northward into the Arctic Ocean2, 3. Tracking expanding species is crucial to conservation efforts and using automatic detectors and classifiers to track the locations of their vocalizations could help. Risso’s (Gg) and Pacific white-sided (Lo) dolphins were documented spreading poleward2 and make very similar sounds, making it difficult for both human analysts and classification algorithms to tell them apart. Variational Mode Decomposition (VMD) has provided both an easier visualization tool4 for human analysts and offers promising capabilities in separating call types of similar spectral and temporal properties. Here we show a new visualization tool and feature extraction technique using VMD that achieves 81.3% accuracy, even when using audio files with faint signals and high background noise levels and without context clues. Because not all dolphins whistle5–7, being able to distinguish between just their pulsed signals is important for tracking them using as many files as possible from under-sampled areas of the ocean. Automating the VMD method and expanding it to other dolphin species that have very similar pulsive signals will lead to a faster understanding of ecosystem dynamics under a changing climate than can currently be achieved.