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Cephalopod International Advisory Council Conference (CIAC 2018) : Cephalopod Research Across Scales: From Molecules to Ecosystems, 12-16 November 2018, St. Petersburg, Florida, USA.-- 1 page, Histioteuthid squids are an important part of marine food webs, being abundant in the diets of many predators. Although they represent a substantial biomass in the deep sea, their systematics are not fully understood; damaged (especially ex-gut-content) and paralarval specimens are difficult to identify morphologically, since most morphological characters presently used to distinguish species involve external photophore patterns. The purpose of this study was to test a morphological hypothesis for the division of the family Histioteuthidae into species groups using two mitochondrial genes (cytochrome c oxidase subunit I [COI] and 16S rRNA). Both the Bayesian and maximum-likelihood analyses supported the division of this family into six genera (formalising previously hypothesised species groups): Calliteuthis, Fragariateuthisgen. nov. Histioteuthis, Histiothauma, Naviagen. nov., andStigmatoteuthis. Barcode Index Numbers based on COI and 16S rRNA were used to distinguish 17 currently accepted species, and revealed up to nine additional species, including potentially new, unnamed species. A DNA barcode reference library of sequences generated in this study is available on the Barcode of Life Data Systems (BOLD), which can be used to confirm identifications or identify damaged specimens, such as those from gut contents. This study is the largest, most complete phylogenetic analysis of this family to date

10 pages, 3 figures, 2 tables, The oegopsid squid family Onychoteuthidae was recently revised based on morphology, but sufficient material for a complementary molecular analysis has not been available until now. In the present study, over 250 sequences of cytochrome c oxidase subunit I (COI) and 16S rRNA for 222 individuals were analysed to create a combined phylogeny for the family. Results support monophyly for the family and all seven onychoteuthid genera (including Moroteuthopsis, established herein as the senior genus name for species formerly attributed to Kondakovia); 29 genetically distinct species were recovered, with the BIN (Barcode Index Number) analysis for COI showing good congruence overall with morphological species groupings. No sequences were available for five additional known species, making the total family diversity likely to exceed 34 species. Seven of the BINs formed in this study appear to represent undescribed taxa, suggesting that even in this relatively well-studied family, much additional work remains before a comprehensive understanding of the diversity and evolutionary relationships for the Onychoteuthidae can be achieved, This work was supported by the New Zealand government under “Coasts & Oceans” core funding from the Ministry of Business, Innovation and Employment (project: Food-web dynamics of New Zealand marine ecosystems)

A comprehensive collection of mainly early life cephalopods that were sampled during two research cruises to the Sargasso Sea with the FRV Walther Herwig III in April 2014, and the RV Maria S Merian in April 2015, is analysed in this work. In 2014, 714 specimens were collected by a pelagic midwater trawl, and further 1,349 specimens by an Isaacs-Kidd Midwater Trawl (IKMT). A total of 2,487 cephalopods were caught during the cruise in 2015. They belonged to 36 species (20 families). The most abundant family was represented by the Flying squids (Ommastrephidae). Identification of cephalopods was supported by DNA barcoding based on partial COI sequences. The subtropical convergence zone (STCZ) was found at approximately 27°N. This frontal system is characterised by a sharp near-surface temperature gradient and divides the Sargasso Sea into a northern and a southern area. This distinction was also reflected in the cephalopod community composition. For example, the cranchiid Leachia lemur prevailed in the northern part, while the cirrate octopod, Japetella diaphana was mainly distributed in the southern part of the study area. PCA and RDA analyses detected a significant correlation between species occurrence and sea surface temperature. Ordination analysis (MDS) showed significant differences in the cephalopod assemblages between day and night with midwater species (Enoploteuthidae, Pyroteuthidae) dominating the night catches, probably due to their upward migration into the top 200 m during the night.