Daniel Sellos’s research while affiliated with Muséum National d'Histoire Naturelle and other places

Gobius xoriguer sp. nov., a new offshore species of goby (Teleostei: Gobiidae: Gobiinae) is described based on three specimens collected in 2010, 2012 and 2018 in the western Mediterranean, off Menorca (Spain), in the Gulf of Lion and off Corsica (France), at 51–104 m depth on coralline algae sea bed. It is easily distinguishable from its Atlantic-Mediterranean congeners by the combination of the following characters: large eyes, ~27-28% of head length; anterior nostril with a small triangular process; 14 soft rays on D2, 13 soft rays on A; enlarged first dorsal fin rays (adult males), with third D1 spine the longest, 23-27 % SL; uppermost P fin rays not free from membrane; long V-shape pelvic fins with vestigial frenum; 50-51 scales on LL; head oculoscapular canal with pores σ, λ, κ, ω, α, β, ρ, ρ1, ρ2, and preopercular canal with pores γ, δ, ε present; row x1 ending anteriorly behind pore β; a groove section between pore ρ and ρ1; suborbital row d discontinuous with large gap below suborbital rows 3 and 4; rows o separated; seven enlarged orange blotches on body side; white dotes on cheek and opercle on an orange background.With a known maximum size of 64 mm TL, it is among the smaller species of Gobius. Bayesian inference and Maximum likelihood phylogenetic tree topologies based on mitochondrial DNA COI sequences (barcoding region), including most Atlantic-Mediterranean Gobius species, support Gobius gasteveni Miller 1974 as the closest relative to Gobius xoriguer sp. nov. These sister species exhibit a high genetic divergence of 9.5% (uncorrected p-distance).

The Cornish sucker, Lepadogaster purpurea (Bonnaterre, 1788), a clingfish species thus far known from the north-eastern Atlantic south to western Africa, the Canary Islands and Madeira, and the western Mediterranean basin, was recently collected in Sicily (Italy), Croatia and Greece. Species identification was based on morphological and/or molecular data. These new Mediterranean records of L. purpurea are the first evidence of the species’ occurrence in the eastern Mediterranean basin and significantly extend its known distribution range, which likely mirrors that of its sister species Lepadogaster lepadogaster (Bonnaterre, 1788).

Gaidropsarus Rafinesque, 1810 is a genus of marine fishes, commonly known as rocklings, comprising 14 living species and showing a high ecological diversity from the intertidal zone to the deep sea. The systematics of this group has been controversial due to a general lack of representative specimens and the conservative morphology exhibited. A multidisciplinary approach combining the analysis of meristic data and the DNA barcode standard was applied in a species delimitation approach. Individuals representing eight valid and three unnamed species were collected, morphologically identified and archived in several museum collections. Comparison of DNA sequences shows complex results, furthering the idea of the difficult identification of specimens based on traditional taxonomy. DNA barcoding supports synonymies, like G. biscayensis-G. macrophthalmus and G. guttatus-G. mediterraneus, agreeing with the extensive overlaps observed in the meristic variables analysed and suggesting a reduction in the number of species. Genetic distances showed pairs of closely related species like G. granti-G. vulgaris and G. argentatus-G. ensis, the latter being only distinguished by one main distinctive character. Four deep-water specimens, morphologically classified only to the genus level, constituted three independent taxa apart from the ones present in this study and with no barcode matches in the repository databases. They could represent new records for the North Atlantic or unknown species of this genus. The results obtained show that more studies will be necessary to solve the systematics of this branch of the Gadiformes. ARTICLE HISTORY

The present study aimed to identify the Aetobatus species present in French Polynesia using DNA barcoding. Our study contributesto a better understanding of the distribution of species in the Aetobatus complex, which is necessary for a correct evaluation of the conservation status of the different species.

Gobius salamansa sp. nov., a new species of tropical eastern Atlantic goby (Teleostei: Gobiidae: Gobiinae) is described from the island of São Vicente in the Republic of Cabo Verde. With adults measuring less than 35 mm TL (total length) it is the smallest species among Gobius. It is easily distinguishable from its Atlantico-Mediterranean congeners thanks to a unique character: an additional posterior ocular head pore, newly named α’, part of the anterior oculoscapular canal and connected to pore α by a suborbital branch. The new species also possesses a rare character among gobiids: a continuous oculoscapular canal, undivided into anterior and posterior parts. The species is distinguishable from its relatives thanks to its distinctive multi-colored (white, red, black, yellow and brown) eyespot, located on the first dorsal fin; by a low number of soft rays on the second dorsal fin (11) and anal fin (9); by row r not divided into two sections; by a divided row d. The two type of specimens were collected at 0.2–0.6 m depth, at the entrance of cracks in compact volcanic boulders forming a rocky islet submerged at high tide. DNA barcoding based on COI of the species compared with sympatric gobiids and species of Atlantico-Mediterranean Gobius reveals a high nucleotide sequence divergence [Kimura’s (1980) two parameter distances of 16.5 %)], with Gobius ateriformis identified as its closest species. A dichotomous key for Gobius–Mauligobius from tropical eastern Atlantic is provided. It is the eleventh gobiid species, and the fourth endemic species, to be described in Cape Verde.

Splendid alfonsino Beryx splendens is a commercial species in several countries, but is not currently exploited in New Caledonia. Information on species biology and genetics can influence the development of fisheries and assist in their management, but the genetic structuring and diversity of B. splendens populations remain largely unknown. To improve knowledge of genetic parameters, we used mitochondrial DNA sequences to conduct a comparative study of populations from throughout the world. Fragments of 815 bp of cytochrome b gene were sequenced and used to interpret the species history. We analyzed 204 individuals representing 14 geographical populations worldwide. A special focus was put on populations from New Caledonia. Analysis of variation between sequences, based on pairwise F statistics and AMOVA, demonstrated a population subdivision between the Atlantic and Indo-Pacific Oceans (Fst = 0.11–0.32; P < 0.05). Minimum-spanning network analysis revealed a mainly star-shaped pattern, with two lineages that may represent population expansion following a bottleneck/founder event and/or suggest colonization by migratory events over large distances. Our observations demonstrated that the species seems to follow the oceanic currents. Analysis of the nucleotide sequences revealed 122 variable sites, which defined numerous haplotypes, some associated with particular geographical regions. These data suggest an extremely high intra-specific genetic diversity, even at small scales. Focusing on the New Caledonia area, statistical analysis did not reveal sub-structuring among samples, suggesting again that at least a fraction of individuals migrate. No significant isolation by distance pattern was observed in this species (R = −0.22; P = 0.79) among seamount populations in the EEZ.

A new species of chimaeroid, Chimaera opalescens n. sp., was described from 31 type specimens caught in the north-eastern Atlantic Ocean at 950-1400 m depth. This species differed from all its congeners by the combination of the following characters: body uniformly pale brown to bronze, iridescent on fresh specimens; unpaired fins brown to purple, uniformly coloured or with pale or whitish edges; iris black; claspers tripartite and divided for a third of their length, not extending beyond the pelvic fins in adults; dorsal spine equal to or shorter than first dorsal fin; ventral caudal lobe equal to or deeper than dorsal caudal lobe. Comparison of DNA sequences of the CO1 gene with those of related species supported C. opalescens n. sp. as a distinct species. Specimens of C. opalescens n. sp. were previously misidentified as Chimaera monstrosa, a species sharing a similar geographical distribution. Chimaera opalescens n. sp. lives in deeper water and is a larger-bodied species than C. monstrosa. The two species were newly exploited by deep-sea fisheries and confused under a single landing name.

The iconic European common skate ( Dipturus batis ) has been described as the first clear case of a fish species brought to the brink of extinction by commercial fishing. Its listing was upgraded to Critically Endangered on the 2006 IUCN Red List of Threatened Species. According to FAO fishery statistics, France is responsible for 60.2% of the 502 tonnes reported as ‘ D. batis ’ in the 2005 world landings. Noticeable phenotypic differences within the species and inconsistencies in published data on its sexual maturation required careful re‐examination of its taxonomy. Morphology, genetics, and life history reveal that two distinct species have been erroneously confused since the 1920s under the single scientific name D. batis . Here it is argued that they should be resurrected as two valid species. The common skate D. batis species‐complex is split into two nominal species, the blue skate (provisionally called D. cf. flossada ) and the flapper skate ( D. cf. intermedia ) with maximum lengths of 143.2 cm and 228.8 cm respectively. This taxonomic confusion puts into question all previously accumulated data based on D. batis . Its endangered status highlights the need for an extensive reassessment of population collapses with accurately identified species. In 2006/2007 an extensive survey (4110 skates, 14.081 tonnes by weight) was conducted in the main French ports of the D. batis species‐complex and relatives ( D. oxyrinchus , D. nidarosiensis and Rostroraja alba ) that are mixed together in landings under the names ‘ D. batis ’ and ‘ D. oxyrinchus ’. The survey reveals that official fishery statistics mask species‐specific declines, due to the mislabelling of five species under only two landing names. Trends in landings since the 1960s and the life history of these species suggest a dramatic decline and collapse of the spawning stock, preventing the recovery of relict populations. The risk of extinction of these depleted species may be higher than previously assessed and might be unavoidable without immediate and incisive conservation action. Copyright © 2009 John Wiley & Sons, Ltd.