All species of the Umboniinae known to occur in the seas off southern Africa and Mozambique are discussed (12 species, 4 new, belonging to 4 genera, 2 new). Observations on the external anatomy, radula and behaviour are given whenever possible. The systematics of the subfamily as a whole are discussed in the light of new data presented. The subfamily contains species with a monopectinate ctenidium and species with a bipectinate ctenidium. Several genera exhibit a morphology intermediate between more typical trochids and the highly derived members of the Umboniinae. The genus Lirularia is considered to be umboniine. Type specimens of a number of extralimital species are illustrated. New genera: Inkaba, type species Inkaba tonga sp. n.; Pseudominolia, type species Solariella splendens Sowerby, 1897. New species: Ethalia bysma, E. electra, E. gilchristae, Inkaba tonga. New synonyms: Minolia variegata Odhner, 1919 = Pseudominolia splendens (Sowerby, 1897); Margarita dilecta A. Adams, 1855 = Antisolarium egenum (Gould, 1849); Minolia eucoronata Sowerby 1905 = Ethminolia impressa (G. & H. Nevill, 1869). New combinations: Solariella splendens Sowerby, 1897, and Margarita articulata Gould, 1861, belong to Pseudominolia gen. n.; Solarium impressum G. & H. Nevill, 1869, Solariella sculpta Sowerby, 1897, Cyclostrema gravieri Lamy, 1909, and Solariella durbanensis Kilburn, 1977, belong to Ethminolia Iredale, 1924. New records: Ethalia carneolata Melvill, 1897, Ethminolia nektonica (Okutani, 1961) and Ethminolia stearnsii (Pilsbry, 1895) are recorded for the first time from the south-western Indian Ocean; Ethminolia durbanensis (Kilburn, 1977), E. gravieri (Lamy, 1909), E. sculpta (Sowerby, 1897) and Pseudominolia splendens (Sowerby, 1897) are recorded from Mozambique for the first time. Lectotypes designated and figured: Ethalia carneolata var. rubrostrigata MelvilJ, 1904; Ethalia minolina var. infralaevior Schepman, 1907; Ethalia striolata A. Adams, 1855; Margarita dilecta A. Adams, 1855; Minolia eucoronata Sowerby, 1905; Minolia glaphyrella Melvill & Standen, 1895; Minolia stearnsii Pilsbry, 1895; Minolia variegata Odhner, 1919; Monilea philippii A. Adams, 1855; Solariella splendens Sowerby, 1897; Solarium impressum G. & H. Nevill, 1869. Types figured: Holotype - Cyclostrema gravieri Lamy, 1909; syntype - Ethalia carneolata Melvill, 1897; holotype - Ethalia minolina Melvill, 1897; holotype - Margarita articulata Gould, 1861; holotypeMinolia edithae Melvill, 1891; holotype - Monilea vernicosa Gould, 1861; holotype - Solariella durbanensis Kilburn, 1977; lectotype - Solariella sculpta Sowerby 1897; holotype - Solarium egenum Gould, 1849; holotype - Talopena gloriola Iredale, 1929; syntype - Trochus eudeli Deshayes, 1863; holotype - Trochus (Solariella) lamprus Watson, 1880.

BENTHEDI

Turbo trochoides Reeve, 1848, Priotrochus sepulchralis Melvill, 1899, and Trochus nabataeus Issei, 1869, are synonymised with Priotrochus obscurus (Wood, 1828). An additional synonym, Trochus signatus Jonas, 1844, is also discussed. Trochus (Aphanotrochus) chrysolaemus von Martens, 1880, is synonymised with Trochus goudoti Fischer, 1878, and Monodonta quadrasi Sowerby, 1899, with Thalotia tricingulata A. Adams, 1853. Lectotypes designated and figured: Trochus obscurus Wood, 1828; Priotrochus sepulchralis Melvill, 1899; Thalotia tricingulata A. Adams, 1853. Other type material figured: Holotype - Turbo trochoides Reeve, 1848; holotype - Trochus (Aphanotrochus) chrysolaemus von Martens, 1880; holotype - Trochus gOlldoti Fischer, 1878; holotype -Monodonta quadrasi Sowerby, 1899. Durban Bay is selected as type locality for Trochus obscurus Wood, 1828. Trochus bicinctlls Philippi, 1849, and Trochus satorius Deshayes, 1863, are regarded as nomina dubia.

BENTHEDI

All species of Chilodontidae known to occur in the south-western Indian Ocean are discussed (27 species, of which eight new, belonging to nine genera, of which three new). Keys to genera and species are provided. Observations on protoconch form, shell microsculpture, radula morphology, operculum shape and external anatomy are given, together with summary biological observations. The genus Agathodonta Cossmann, 1918 is not considered to be applicable to the extant species for which it has been recently used and a new genus is proposed for these living forms. Type specimens of a number of extralimital species examined for comparative purposes are illustrated. New genera: Ascetostoma, Clypeostoma and Pholidotrope. New species: Clypeostoma reticulatum, Danilia boucheti, Danilia textilis, Herpetopoma serratocinctum, Herpetopoma stictum, Pholidotrope gloriosa, Vaceuchelus cretaceus and Vaceuchelus jayorum. New synonyms: Cantharidus pliciferus Schepman, 1908 = Perrinia angulifera (A. Adams, 1853); Turcica (Perrinia) waiwailevensis Ladd, 1982 and Herpetopoma eboreum Vilvens & Heros, 2003 = Herpetopoma xeniolum (Melvill, 1918); Trochus alabastrum Reeve, 1858 = Euchelus asper (Gmelin, 1791). New combinations: Agathodonta elongata Vilvens, 2001, A. meteorae Neubert, 1998, A. nortoni McLean, 1984, Euchelus townsendianus Melvill & Standen, 1903 and Turcica salpinx Barnard, 1964 are transferred to Clypeostoma gen. n.; Diloma verruca Gould, 1861, Euchelus seychellarum G. & H. Nevill, 1869, Euchelus xeniolum Melvill, 1918, Turcica helix Barnard, 1964 and T. waiwailevensis Ladd, 1982 are transferred to Herpetopoma; Euchelus gemmula Turton, 1932 is transferred to Vaceuchelus; Euchelus providentiae Melvill, 1909 and E. ringens Schepman, 1908 are transferred to Ascetostoma gen. n.; Stomatella cumingii A. Adams, 1854 is transferred to Granata; Turcica konos Barnard, 1964 is transferred to Perrinia. New records for the south-western Indian Ocean: Clypeostoma meteorae (Neubert, 1998); Clypeostoma cf. nortoni (McLean, 1984); Granata cumingii (A. Adams, 1854); Herpetopoma instrictum (Gould, 1849); Herpetopoma ?naokoae Poppe, Tagaro & Dekker, 2006; Herpetopoma xeniolum (Melvill, 1918); Perrinia angulifera (A. Adams, 1853). New records for South Africa: Ascetostoma providentiae (Melvill, 1909); Herpetopoma ?naokoae Poppe, Tagaro & Dekker, 2006; Perrinia angulifera (A. Adams, 1853). Lectotypes designated for: Euchelus favosus Melvill & Standen, 1896; Euchelus gemmula Turton, 1932; Euchelus natalensis Smith, 1906; Euchelus seychellarum G. & H. Nevill, 1869; Euchelus townsendianus Melvill & Standen, 1903; Monodonta alveolata A. Adams, 1853; Monodonta angulifera A. Adams, 1853; Stomatella articulata A. Adams, 1850; Turbo semilugubris Deshayes, 1863. Type locality designations and emendations: Type locality for Stomatella cumingii Adams, 1854, designated to be tropical East Africa; type locality for Turcica salpinx Barnard, 1964, selected to be 'off Cape Morgan, 77 fath.' [-141 m]; type locality of Turcica stellata A. Adams, 1864, emended from 'China Seas' to Gulf of Suez, Red Sea. Danilia Brusina, 1865 is deemed a nomen protectum and Heliciella O.G. Costa, 1861 a nomen oblitum.

ATIMO VATAE, BENTHEDI, LAGON, MAINBAZA, MD32 (REUNION), MIRIKY

All species of Umboniinae known to occur in New Caledonia are discussed (19 species, 8 new, belonging to 10 genera, 2 new) and a key to genera is provided. An additional new species is described from the Bismarck Sea. Nine species are perhaps endemic to New Caledonia. The diversity of the fauna is comparable to that of Japan and Australia, both regions of much greater extent and spanning a much broader latitudinal range. Ethalia lampra (Watson, 1880), previously known only from the original HMS Challenger material from Fiji, has been rediscovered in New Caledonia. Re-examination of the type material of Monilea apicina Gould, 1861 has led to a re-interpretation of the application of this name. Type specimens of a number of additional umboniine species examined for comparison are illustrated. Two new genera are proposed: Kanakina gen. nov. and Tylorhaphe gen. nov. Nine new species are described: Ethalia anomphala sp. nov., Ethminolia hickmanae sp. nov., Sericominolia porcata sp. nov., S. safrocincta sp. nov., Talopena maestratii sp. nov., Tylorhaphe alisae gen. et sp. nov., T. fritillaria gen. et sp. nov., T. luteopicta gen. et sp. nov. and T. wallacei gen. et sp. nov. Revised status: Talopena Iredale, 1918 is recognised as a full genus rather than a subgenus or synonym of Monilea Swainson, 1840. Minolia agapeta Melvill & Standen, 1896 is considered a distinct species, no longer to be regarded as a junior synonym of Monilea apicina Gould, 1861. Trochus (Monilea) lifuanus Fischer, 1878 is considered a distinct species, no longer to be regarded as a junior synonym of Monilea vernicosa Gould, 1861. New combinations: Monilea incerta Iredale, 1912 is reassigned to Talopena Iredale, 1918; Monilea apicina Gould, 1861, Monilea menkei A. Adams, 1855, Monilea philippii A. Adams, 1855, Pseudominolia tramieri Poppe, Tagaro & Dekker, 2006, Trochus belcheri Philippi, 1850, Trochus calyculus W. Wood, 1828, and Trochus (Monilea) masoni G. Nevill & H. Nevill, 1874 are all referred to Talopena Iredale, 1918. Minolia glaphyrella Melvill & Standen, 1895 is transferred to Kanakina gen. nov. Type localities: Nouméa, New Caledonia is designated as the type locality for Trochus nucleus Philippi 1850; the type locality ‘Port Jackson’ originally given for Monilea apicina Gould, 1861 is considered erroneous and is emended to Lansdowne Bank. New records for New Caledonian marine ecoregion: Ethalia lampra (Watson, 1880), Talopena apicina (Gould, 1861) and ‘Talopena’ tramieri (Poppe, Tagaro & Dekker, 2006).

CHALCAL 1, CORAIL 2, EXBODI, KANACONO, KANADEEP, KAVIENG 2014, KOUMAC 2.1, KOUMAC 2.3, LAGON, LIFOU 2000, MONTROUZIER, MUSORSTOM 6, SALOMON 1, Restreint

The vetigastropod material collected on Walters Shoal during Cruise MD208 of the Tropical Deep-Sea Benthos programme is documented. In total, 50 species were obtained, 30 of which are new and apparently endemic to the seamount. Of the other 20 species, eight are regionally endemic to the south-western Indian Ocean, 11 are more widely distributed in the Indo-West Pacific and one is possibly of deep-water Atlantic origin. The primary affinities of the fauna are with warm temperate South Africa and the tropical western Indian Ocean, but one species is potentially a seamount endemic of southern affinity. A new pseudococculinid genus living on decomposing bird feathers is described, a biogenic substrate association previously unknown in the Mollusca. The following new genera are described: Imbricoscelis gen. nov. and Pterodacna gen. nov. The following new species are described: Akritogyra crenulata sp. nov., Bathymophila williamsae sp. nov., Benthobrookula araneum sp. nov., Be. galeneae sp. nov., Be. laticostata sp. nov., Be. scalaroides sp. nov., Be. semisculpta sp. nov., Bruceina areneformis sp. nov., Calliostoma pantopunctatum sp. nov., Cantrainea herosae sp. nov., Carinastele achrosta sp. nov., Cornisepta marshalli sp. nov., Emarginula lentiginosa sp. nov., E. nodulicostata sp. nov., E. retrogyra sp. nov., E. salebrosa sp. nov., Fluxinella dufresneae sp. nov., Gibbula roseosticta sp. nov., Hadroconus scobina sp. nov., Kaiparathina monticola sp. nov., Lissotesta wareni sp. nov., Microcollonia miniata sp. nov., Mikro crassus sp. nov., Parviturbo cicatricosus sp. nov., Phragmomphalina candida sp. nov., Pterodacna boucheti gen. et sp. nov., Solariella asaphea sp. nov., Spinicalliotropis lepidota sp. nov., Stomatella multilirata sp. nov. and Trenchia mcleani sp. nov. The following new combinations are proposed: Brookula coronis Barnard, 1963 is transferred to Imbricoscelis gen. nov., Cantharidus nolfi Poppe, Tagaro & H. Dekker, 2006 is transferred to Kaiparathina Laws, 1941 and Solariella incisura Melvill, 1909 is transferred to Phragmomphalina Herbert & Williams, 2020. The following new synonyms are proposed: Carinastele wareni Vilvens, 2014 is a synonym of Bruceina cognata (Marshall, 1988); Fluxinella stellaris Bozzetti, 2008 is a synonym of Agagus stellamaris Herbert, 1991.

Walters Shoal

The vetigastropod material collected on Walters Shoal during Cruise MD208 of the Tropical Deep-Sea Benthos programme is documented. In total, 50 species were obtained, 30 of which are new and apparently endemic to the seamount. Of the other 20 species, eight are regionally endemic to the south-western Indian Ocean, 11 are more widely distributed in the Indo-West Pacific and one is possibly of deep-water Atlantic origin. The primary affinities of the fauna are with warm temperate South Africa and the tropical western Indian Ocean, but one species is potentially a seamount endemic of southern affinity. A new pseudococculinid genus living on decomposing bird feathers is described, a biogenic substrate association previously unknown in the Mollusca. The following new genera are described: Imbricoscelis gen. nov. and Pterodacna gen. nov. The following new species are described: Akritogyra crenulata sp. nov., Bathymophila williamsae sp. nov., Benthobrookula araneum sp. nov., Be. galeneae sp. nov., Be. laticostata sp. nov., Be. scalaroides sp. nov., Be. semisculpta sp. nov., Bruceina areneformis sp. nov., Calliostoma pantopunctatum sp. nov., Cantrainea herosae sp. nov., Carinastele achrosta sp. nov., Cornisepta marshalli sp. nov., Emarginula lentiginosa sp. nov., E. nodulicostata sp. nov., E. retrogyra sp. nov., E. salebrosa sp. nov., Fluxinella dufresneae sp. nov., Gibbula roseosticta sp. nov., Hadroconus scobina sp. nov., Kaiparathina monticola sp. nov., Lissotesta wareni sp. nov., Microcollonia miniata sp. nov., Mikro crassus sp. nov., Parviturbo cicatricosus sp. nov., Phragmomphalina candida sp. nov., Pterodacna boucheti gen. et sp. nov., Solariella asaphea sp. nov., Spinicalliotropis lepidota sp. nov., Stomatella multilirata sp. nov. and Trenchia mcleani sp. nov. The following new combinations are proposed: Brookula coronis Barnard, 1963 is transferred to Imbricoscelis gen. nov., Cantharidus nolfi Poppe, Tagaro & H. Dekker, 2006 is transferred to Kaiparathina Laws, 1941 and Solariella incisura Melvill, 1909 is transferred to Phragmomphalina Herbert & Williams, 2020. The following new synonyms are proposed: Carinastele wareni Vilvens, 2014 is a synonym of Bruceina cognata (Marshall, 1988); Fluxinella stellaris Bozzetti, 2008 is a synonym of Agagus stellamaris Herbert, 1991.

Walters Shoal

The abyssal and hadal Buccinoidea from the north-western Pacific formerly attributed to the genera Tacita and Calliloncha were analyzed for the first time using both multilocus molecular and morphological data. The results allow re-evaluation of the inter- and intrageneric variability of morphological characters and demonstrate that Tacita, Calliloncha and Paracalliloncha are synonyms of Bayerius, a genus widely distributed in the Pacific Ocean. In our reconstructed phylogeny the genus forms a maximally supported clade with Pararetifusus tenuis and Turrisipho dalli. At present, Bayerius includes 10 species, two of which are described herein as new to science, B. inflatus sp. nov. and B. nekrasovorum sp. nov. with one additional undescribed species represented in our material by a single specimen. The genus is reviewed, with the addition of new data on anatomy and distribution, based on newly obtained material. B. peruvianus is synonymized with B. zenkewitchi. Calliloncha nankaiensis together with Costaria crosnieri are attributed to a new genus, Warenius gen. nov., which clusters with several genera of Buccinoidea from biogenic substrata.

ATIMO VATAE, AURORA 2007, KARUBENTHOS 2012, MIRIKY, PANGLAO 2005, PAPUA NIUGINI, SALOMON 2, TAIWAN 2004, ZhongSha 2015

A new genus, Arxellia, is described in the family Solariellidae. Nine species are referred to this taxon, eight of which are new and are described in this paper (Arxellia trochos n. sp., Arxellia boucheti n. sp., Arxellia herosae n. sp., Arxellia helicoides n. sp., Arxellia tracheia n. sp., Arxellia thaumasta n. sp., Arxellia maestratii n. sp. And Arxellia erythrea n. sp.). The previously described species Bathymophila tenorioi Poppe, Tagaro & Dekker, 2006 is reassigned to Arxellia.

BATHUS 2, BATHUS 3, BIOCAL, BIOPAPUA, BORDAU 1, BORDAU 2, CHALCAL 2, EXBODI, LITHIST, MUSORSTOM 6, MUSORSTOM 7, MUSORSTOM 8, NORFOLK 1, NORFOLK 2, PANGLAO 2005, SMIB 8, VOLSMAR

The assignment of species to the vetigastropod genus Solariella Wood, 1842, and therefore the family Solariellidae Powell, 1951, is complicated by the fact that the type species (Solariella maculata Wood, 1842) is a fossil described from the Upper Pliocene. Assignment of species to genera has proved difficult in the past, and the type genus has sometimes acted as a ‘wastebasket’ for species that cannot easily be referred to another genus. In the light of a new systematic framework provided by two recent publications presenting the first molecular phylogenetic data for the group, we reassess the shell characters that are most useful for delimiting genera. Shell characters were previously thought to be of limited taxonomic value above the species level, but this is far from the case. Although overall shell shape is not a reliable character, our work shows that shell characters, along with radular and anatomical characters, are useful for assigning species to genera. Sculpture of the early teleoconch (the region immediately following the protoconch) and the columella are particularly useful characters that have not been used regularly in the past to distinguish genera. However, even with the combination of all morphological characters used in this study (shell, radular and eye), a few species are still difficult to assign to genera and in such cases molecular systematic data are essential. In the present study, we discuss 13 genera—12 of which were recovered as well-supported clades in recent molecular systematic studies—and provide morphological characters to distinguish them. We describe several new taxa: Chonospeira n. gen. (referred to as ‘clade B’ in previous molecular systematic studies), Phragmomphalina n. gen. (Bathymophila in part in molecular systematic studies) and Phragmomphalina vilvensi n. sp. (type species of Phragmomphalina n. gen.). We synonymize Hazuregyra Shikama, 1962 with Minolia A. Adams, 1860, Minolia subangulata Kuroda & Habe, 1952 with Minolia punctata A. Adams, 1860 and M. gemmulata Kuroda & Habe, 1971 with M. shimajiriensis (MacNeil, 1960). We also present the following new combinations: Bathymophila bairdii (Dall, 1889), B. dawsoni (Marshall, 1979), B. regalis (Marshall, 1999), B. wanganellica (Marshall, 1999), B. ziczac (Kuroda & Habe in Kuroda, Habe & Oyama, 1971), Chonospeira nuda (Dall, 1896), C. iridescens (Habe, 1961), C. ostreion (Vilvens, 2009), C. strobilos (Vilvens, 2009), Elaphriella corona (Lee & Wu, 2001), E. diplax (Marshall, 1999), E. meridiana (Marshall, 1999), E. olivaceostrigata (Schepman, 1908), E. opalina (Shikama & Hayashi, 1977), Ilanga norfolkensis (Marshall, 1999), I. ptykte (Vilvens, 2009), I. zaccaloides (Vilvens, 2009), Minolia shimajiriensis (MacNeil, 1960), M. watanabei (Shikama, 1962), Phragmomphalina alabida (Marshall, 1979), P. diadema (Marshall, 1999), P. tenuiseptum (Marshall, 1999), Spectamen euteium (Vilvens, 2009), S. basilicum (Marshall, 1999), S. exiguum (Marshall, 1999) and S. flavidum (Marshall, 1999).

EXBODI, KARUBENTHOS 2012, MAINBAZA, MIRIKY, PANGLAO 2004

ABSTRACT We present here the most taxon-rich phylogeny for the trochid subfamily Umboniinae published to date, with representatives from 14 of the 19 known genera, and as a result show that Umboniinae needs comprehensive taxonomic and systematic revision. We identified one clade corresponding to a new genus with four species collected from deeper water than is typical of most umboniine taxa and one new species likely belonging to a second, undescribed genus (all to be described elsewhere). Only four genera, as currently interpreted were recovered, as monophyletic: Umbonium, Lirularia, Monilea and Rossiteria. Zethalia (monotypic for extant taxa), Pseudominolia, Isanda and Parminolia were all represented by a single species (the latter by Gibbula vanwalleghemi; Poppe, Tagaro & Dekker, 2006). Conotalopia, Ethalia, Ethaliella, Ethminolia, Sericominolia and Vanitrochus were all polyphyletic. We formally recognize the following new combinations: Sericominolia glaphyrella (Melvill & Standen, 1895), Sericominolia vitiliginea (Menke, 1843), Vanitrochus ornatus (Sowerby III, 1903) and Parminolia vanwalleghemi (Poppe, Tagaro & Dekker, 2006), although further molecular studies are desirable to confirm these decisions. The first three generic reassignments make Sericominolia and Vanitrochus monophyletic in our tree. We also suggest that Ethaliella cf. rhodomphala (Souverbie, 1875) should be transferred to one of several clades with species previously assigned to Ethminolia, for which an appropriate genus name has not yet been resolved. This decision makes Ethaliella monophyletic. We also identified several cryptic species complexes, including Rossiteria nucleus (Philippi, 1850), the type species of Rossiteria. The phylogeny presented is a first step towards a more resolved systematic framework for Umboniinae and will allow future studies of key morphological innovations.

ATIMO VATAE, AURORA 2007, EXBODI, INHACA 2011, MIRIKY, PANGLAO 2004, SANTO 2006

Recent expeditions have revealed high levels of biodiversity in the tropical deep-sea, yet little is known about the age or origin of this biodiversity, and large-scale molecular studies are still few in number. In this study, we had access to the largest number of solariellid gastropods ever collected for molecular studies, including many rare and unusual taxa. We used a Bayesian chronogram of these deep-sea gastropods (1) to test the hypothesis that deep-water communities arose onshore, (2) to determine whether Antarctica acted as a source of diversity for deep-water communities elsewhere and (3) to determine how factors like global climate change have affected evolution on the continental slope. We show that although fossil data suggest that solariellid gastropods likely arose in a shallow, tropical environment, interpretation of the molecular data is equivocal with respect to the origin of the group. On the other hand, the molecular data clearly show that Antarctic species sampled represent a recent invasion, rather than a relictual ancestral lineage. We also show that an abrupt period of global warming during the Palaeocene Eocene Thermal Maximum (PETM) leaves no molecular record of change in diversification rate in solariellids and that the group radiated before the PETM. Conversely, there is a substantial, although not significant increase in the rate of diversification of a major clade approximately 33.7Mya, coinciding with a period of global cooling at the EoceneOligocene transition. Increased nutrients made available by contemporaneous changes to erosion, ocean circulation, tectonic events and upwelling may explain increased diversification, suggesting that food availability may have been a factor limiting exploitation of deep-sea habitats. Tectonic events that shaped diversification in reef-associated taxa and deep-water squat lobsters in central Indo-West Pacific were also probably important in the evolution of solariellids during the Oligo-Miocene.

AURORA 2007, BENTHAUS, BERYX 11, BIOPAPUA, BOA1, BORDAU 1, CONCALIS, EBISCO, MAINBAZA, MIRIKY, NORFOLK 1, NORFOLK 2, PANGLAO 2004, PANGLAO 2005, SALOMON 1, SALOMON 2, TAIWAN 2001, TARASOC, TERRASSES