New sublittoral species of Laonice (Annelida: Spionidae) from southern Asian coasts.

Four new species of Laonice (Annelida: Spionidae) are described from the southern and southeastern coasts of Asia: L. (Laonice) persica sp. nov., L. (Laonice) siamica sp. nov., L. (Sarsiana) apicelamella sp. nov. and L. (Sarsiana) andamanica sp. nov. Materials were collected within the scope of different environmental surveys performed by the consulting company Créocéan, ranging from the Persian Gulf (Indian Ocean) on the west, to the Gulf of Siam (Pacific Ocean) on the east. In addition, specimens found in the Gulf of Siam are tentatively attributed to L. (Sarsiana) sinica, and an English translation of the species description is provided for the first time. Different species subgroups within L. (Sarsiana) are also recognized based on key morphologic characters, though their phylogenetic relevance requires further confirmation. The scientific value of biological material collected during environmental surveys is emphasized, and contractors are encouraged to deposit reference collections in public natural history collections.

Revision of the Laonice bahusiensis complex (Annelida: Spionidae) with a description of three new species.

The morphological reexamination of specimens previously identified as Laonice bahusiensis Sderstrm, 1920 from North European and Mediterranean collections, supported by the molecular analysis of freshly collected material, enabled the recognition of four different species in the region: the genuine L. bahusiensis, L. irinae n. sp. from North European waters, and L. grimaldii n. sp. and L. mediterranea n. sp. from the Mediterranean Sea. The morphology of these species is described and illustrated, and their distributions are clarified based on old and new materials. A key for their identification is also provided. The Bayesian analysis of the COI sequences (483 bp) showed that these four species form a clade, namely the L. bahusiensis species complex, morphologically characterized by the continuous dorsal crests on postbranchiate chaetigers in the adults. The genetic p-distances between the species of the complex ranged from 13.27% to 17.99%, while the intraspecific variability ranged from 0.6% to 1.57%. Together with the sister species Laonice cirrata (Sars, 1851), the L. bahusiensis complex formed the Laonice (Laonice) clade, which is morphologically characterized by the prostomium fused with the anterior peristomial margin. However, the monophyly of the L. bahusiensis complex, as well as that of the clade Laonice (Laonice), needs to be further supported through the analysis of a greater set of genes from a larger number of species.

Two new deep-sea species of Laonice (Annelida: Spionidae) from the Mediterranean Sea.

Two new deep-sea species of the genus Laonice belonging to the subgenera Sarsiana and Appelloefia respectively, are described from the Mediterranean Sea. Complete specimens of the subgenus Appelloefia were studied for the first time, and the new information collected raised questions on the boundaries between the subgenera Appelloefia and Norgensia. The presence of characters in L. barcinensis sp. nov. previously considered to be exclusive to each these two subgenera suggests that they should be regarded as synonymous. The name Appelloefia being given precedence here, according to the Principle of the First Reviser. A correction is made regarding the depth range of Laonice rasmusseni Sikorski Pavlova, 2018.

Mesoparasitic copepods (Copepoda: Cyclopoida) associated with polychaete worms in European seas.

A large collection of mesoparasitic copepods from polychaete hosts collected in northern European waters was examined. The term mesoparasitic refers to highly transformed copepods where the adult female attaches by embedding part of its body in the host. Representatives of five known familes were found and a new family is established. A single new species, Bradophila minuta sp. nov., was described in the family Bradophilidae. It occurred exclusively on the flabelligerid Diplocirus glaucus (Malmgren, 1867). Two genera of the family Herpyllobiidae were represented: Herpyllobius Steenstrup Lütken, 1861 and Eurysilenium M. Sars, 1870. Herpyllobius arcticus Steenstrup Lütken, 1861 was found on at least five different polynoid hosts, two of which, Harmothoe fragilis Moore, 1910 and Antinoe sp., were new host records. A new species, H. cluthensis sp. nov. was described from Malmgrenia species in Scottish waters. The large species, Herpyllobius cordiformis Lützen, 1964, was collected in Arctic waters from Eunoe cf. oerstedi. It is the first report of this parasite in Europe. The common parasite H. polynoes (Krøyer, 1864) was found on six different polynoid hosts, three of which, Harmothoe bifera, Malmgreniella mcintoshi Tebble Chambers, 1982 and Eunoe ?barbata are new host records. Eurysilenium truncatum M. Sars, 1870 was collected from Eucranta villosa Malmgren, 1866, Eunone sp., and Gattyana cirrhosa (Pallas, 1766). The material from Eucranta villosa caught at 72.6ºN comprises both a new host record and is the most northerly report of this parasite. Specimens of Eurysilenium which differed from E. truncatum in a number of features were found on Harmothoe fragilis and H. impar (Johnston, 1839). A new family, the Pholoicolidae, is established to accommodate Pholicola chambersae gen. et sp. nov., parasitic on Pholoe pallida Chambers, 1985. The family Phyllodicolidae was represented by all three of its known species: Phyllodicola petiti (Delamare Deboutteville Laubier, 1960), Cyclorhiza eteonicola Heegaard, 1942 and C. megalova Gotto Leahy, 1988. The former was found on Eumida ockelmanni Eibye-Jacobsen, 1987, a new host record. A single ovigerous female of C. eteonicola was collected from a new host, Eteone spetsbergensis Malmgren, 1865. Cyclorhiza megalova was common on Eteone longa (Fabricius, 1780) and E. longa/flava complex. A rich diversity of members of the family Saccopsidae was found, including three known species of Melinnacheres M. Sars, 1870 plus nine new species placed in four new genera. Melinnacheres was represented by M. ergasiloides M. Sars, 1870, M. steenstrupi Bresciani Lützen, 1961 and M. terebellidis Levinsen, 1878. Melinnacheres ergasiloides was found on Melinna elizabethae McIntosh, 1914, M. steenstrupi on members of the Terebellides stroemi-complex and T. atlantis Williams, 1984, while M. terebellidis was found on the T. stroemi-complex and on T. shetlandica Parapar, Moreira O'Reilly, 2016. A new genus, Trichobranchicola gen. nov., was established to accommodate T. antennatus gen. et sp. nov., a parasite of Trichobranchus sikorskii Leontovich Jirkov in Jirkov, 2001, T. glacialis Malmgren, 1866 and Trichobranchus sp. The second new genus, Lanassicola gen. nov., was established to accommodate the type species, Lanassicola arcticus gen. et sp. nov. parasitic on Lanassa venusta (Malm, 1874), plus two additional species, L. bilobatus gen. et sp. nov. on Lanassa nordenskjoeldi Malmgren, 1866, and L. dorsilobatus gen. et sp. nov. on Proclea graffii (Langerhans, 1884). A new subfamily, Euchonicolinae, was established within the Saccopsidae to accommodate two new genera, Euchonicola gen. nov. and Euchonicoloides gen. nov. The type species of Euchonicola gen. nov. is E. caudatus gen. et sp. nov., a parasite of Euchone sp., and it includes two other species, E. linearis gen. et sp. nov. on Chone sp., and E. parvus gen. et sp. nov. on Euchone sp. The type species of Euchonicoloides gen. nov. is E. elongatus gen. et sp. nov. found on a host belonging to the genus Euchone, and it also includes Euchonicoloides halli gen. et sp. nov. from Jasmineira caudata Langerhans, 1880. Four species of the family Xenocoelomidae were found: Xenocoeloma alleni (Brumpt, 1897), X. brumpti Caullery Mesnil, 1915, X. orbicularis sp. nov. and Aphanodomus terebellae (Levinsen, 1878). Xenocoeloma alleni was found on four different species of Polycirrus and on Amaeana trilobata (M. Sars, 1863) and X. brumpti was found on Polycirrus norvegicus Wollebaek, 1912. Xenocoeloma orbicularis sp. nov. occurred only on Paramphitrite birulai (Ssolowiew, 1899). Aphanodomus terebellae was found on three hosts, only one of which, Leaena abranchiata was new.

Two new species of Laonice (Norgensia) (Spionidae, Polychaeta) from subtropical Atlantic and subequatorial Pacific coasts of North America.

Two new species, Laonice costaricensis sp. nov. and L. rasmusseni sp. nov., belonging to the subgenus Norgensia Sikorski et al., 2017 were found in material from the Pacific collected from Coco Island off the coast of Costa Rica and from the Atlantic collected from Sapelo Island off the coast of Georgia (USA), respectively. Laonice cosaricensis is very close morphologically to L. lemniscata but without transdorsal membranes and having as usual capillaries in several anterior parapodia arranged in three vertical rows. Laonice rasmunsseni has genital pouches starting much anteriorly than in all known species from this subgenus. An identification key for the species belonging to this subgenus is given.

A mega-cryptic species complex hidden among one of the most common annelids in the North East Atlantic.

We investigate mitochondrial (COI, 16S rDNA) and nuclear (ITS2, 28S rDNA) genetic structure of North East Atlantic lineages of Terebellides, a genus of sedentary annelids mainly inhabiting continental shelf and slope sediments. We demonstrate the presence of more than 25 species of which only seven are formally described. Species boundaries are determined with molecular data using a broad range of analytical methods. Many of the new species are common and wide spread, and the majority of the species are found in sympatry with several other species in the complex. Being one of the most regularly encountered annelid taxa in the North East Atlantic, it is more likely to find an undescribed species of Terebellides than a described one.

Three new species of Laonice (Polychaete: Spionidae) from West and Southwest Africa.

Three new species of Laonice (Polychaete: Spionidae): L. galatheae, L. cricketae, L. olgae-are described from South and West Africa (along the coast from 31°14.1'S to 04°44'N) based on Danish and South African zoological collections. Arguments relative to the morphological heterogeneity of the genus Laonice are advanced. The arguments are based on the following characters: degree of fusion of prostomium with peristomium at the anterior margin, degree of variability of all numerical characters, arrangement of anterior capillaries in two or more vertical rows, presence or absence of transversal dorsal membranous crests in the "post nuchal organ" and presence of genital pouches only on very limited number of segments or other pattern. Authors think it is obvious today an existence of at least four morphologically separate groups of species inside the Laonice-genus: "L. cirrata", "L. sarsi", "L. appelloefi" and "L. norgensis" groups. Eight species names from 34 valid names in the genus are still with unclear affiliation. L. quadridentata is treated now as a junior synonym of L. brevicornis. An opinion is expressed about L. insolita not belonging to the genus Laonice because of discrepancy the generic diagnosis.

A new genus and family of copepods (Crustacea: Copepoda) parasitic on polychaetes of the genus Jasmineira Langerhans, 1880 (family Sabellidae) in the northeastern Atlantic.

A new genus and species of copepod, Jasmineiricola mackiei n. gen. et n. sp., parasitic on at least three species of the sabellid polychaete genus Jasmineira Langerhans, 1880 is described. The adult female is mesoparasitic, living with part of its body (the endosoma) embedded within the host and part (the ectosoma) protruding through the host's body wall. The endosoma consists of a well defined head region carried anteriorly on the trunk which has paired lateral lobes housing the ovaries. The head bears a rosette-like array of eight slender lobes, which are probably derived from the mouthparts. The only limbs present on the trunk are the subchelate maxillipeds positioned immediately posterior to the head. The ectosoma consists of a posterior genito-abdominal lobe bearing paired genital apertures. The male is unknown. The new genus cannot be placed in any of the five existing families of mesoparasitic copepods on polychaete hosts and is treated as the type of a new monotypic family, the Jasmineiricolidae. The new species occurs over a depth range from 19 to 279 m, and is widely distributed from UK coastal waters to Norwegian waters inside the Arctic Circle.

Copepods associated with polychaete worms in European seas.

Descriptions are given of 18 species of copepods that live in symbiotic association with polychaete worms in European Seas. Three new genera and six new species of the family Clausiidae Giesbrecht, 1895 are described: Boreoclausia rectan. gen. et n. sp. is described from Galathowenia fragilis (Nilson & Holthe, 1985), Boreoclausia holmesi n. gen. et n. sp.is described from Myriochele danielsseni Hansen, 1879, Sheaderia bifida n. gen. et n. sp. from Euclymene oerstedii (Claparède, 1863), Vivgottoia garwoodi n. gen. et n. sp., was found inside the tail fragment of a terebellid host (probably Phisidia aurea Southward, 1956), Rhodinicola tenuis n. sp. from an unknown host, and R. similis n. sp., from Rhodine gracilor (Tauber, 1879). In addition, four other clausiid species, Clausia lubbockii Claparède, 1863, Mesnilia cluthae (T. and A.Scott, 1896), Rhodinicola gibbosus Bresciani, 1964 and R. rugosum (Giesbrecht, 1895), are redescribed in detail on the basis of newly collected material. The previously-unknown hosts of C. lubbockii were found to be species of the spionid polychaete genus Dipolydora Verrill, 1881. Clausia uniseta Bocquet & Stock, 1960 were recognized as a junior subjective synonym of C. lubbockii, and Mesnilia martinensis Canu, 1898 was recognized as a junior subjective synonym of M. cluthae. The sole species of the monotypic family Anomoclausiidae Gotto, 1964, Anomoclausia indrehusae Gotto, 1964, is redescribed based on new material. The host of A. indrehusae, reported here for the first time, is the spionid Pseudopolydora paucibranchiata (Okuda, 1937). Four new species of the family Nereicolidae Claus, 1875 are described, three belonging to the genus Anomopsyllus Sars, 1921: Anomopsyllus bifurcus n. sp. from Notomastus latericeus M. Sars, 1851, A. geminus n. sp. from Ampharete lindstroemi Malmgren, 1867, and A. hamiltonae n. sp., from Mugga wahrbergi Eliasson, 1955. The fourth new species is Vectoriella gabesensis n. sp., both sexes of which are described from the paraonid Aricidea catherinae Laubier, 1967 collected in the Mediterranean Sea off the coast of Tunisia. Another nereicolid, Sigecheres brittae Bresciani, 1964 is redescribed based on new material collected from the type host Sige fusigera Malmgren, 1865. It is recognized as a junior subjective synonym of Nereicola concinna T. Scott, 1902 and the valid name of this taxon becomes Sigecheres concinna (T. Scott, 1902) new combination. A new species of the family Spiophanicolidae Ho, 1984, Spiophanicola atlanticus n. sp., is described based on European material. Previously European material of Spiophanicola Ho, 1984 has been reported as S. spinulosus Ho, 1984, but based on consistent differences between the Californian S. spinulosus and material from Norway and the British Isles, there is sufficient justification to establish a new species for the European material. Finally one new genus and species is described which cannot be placed, with confidence, in any existing family. This new parasite, Notomasticola frondosus n. gen. et n. sp., is based on material from two hosts, a spionid (Pseudopolydora paucibranchiata) and a capitellid (Notomastus latericeus). It is highly derived and may represent a terminal branch within an existing family. The cluster of families using polychaetes as hosts is in need of revision based on a comprehensive phylogenetic analysis.