(PDF) <strong>Lost and found: The Eocene family Pyramimitridae (Neogastropoda) discovered in the Recent fauna of the Indo-Pacific</strong>
Pierre Lozouet independent.academia.edu
Lost and found: The Eocene family Pyramimitridae (Neogastropoda) discovered in the Recent fauna of the Indo-Pacific
The paleobiodiversity of the Volutidae (Mollusca: Gastropoda) of the Ranikot Group (Sindh, Pakistan) and particularly of the Lakhra Formation (SBZ 5 biozone, Earliest Eocene), is reconsidered on the basis of new material collected during recent field trips. Ten new species are described (Mitreola brohii sp. nov., Lyrischapa vredenburgi sp. nov., L. brevispira sp. nov., Athleta (Volutopupa) citharopsis sp. nov., A. (Volutocorbis) lasharii sp. nov., Volutilithes welcommei sp. nov., V. sindhiensis sp. nov., Pseudaulicina coxi sp. nov., Sindhiluta lakhraensis sp. nov. and Pakiluta solangii sp. nov.) and one species is in open nomenclature (Lyria sp.). Three new genera are described: Lyriopsis gen. nov. [Volutinae, ?Lyriini, type species: Lyriopsis cossmanni (Vredenburg, 1923)], Sindhiluta gen. nov. [Volutilithinae, type species: Sindhiluta lakhraensis n. sp.] and Pakiluta gen. nov. [?Volutodermatinae, type species: Pakiluta solangii n. sp.]. Two new combinations are proposed: Lyriopsis cossmanni (Vredenburg, 1923) comb. nov. and Athleta (Volutopupa) intercrenatus (Cossmann & Pissarro, 1909) comb. nov. Lectotypes are designated for Lyria cossmanni Vredenburg, 1923, L. feddeni Vredenburg, 1923, Volutospina noetlingi Cossmann & Pissarro, 1909, V. intercrenata Cossmann & Pissarro, 1909 and Athleta (Volutocorbis) victoriae Vredenburg, 1923. With 21 species, this volutid fauna is the most diverse recorded from the Tethys Ocean during Earliest Eocene time. The assemblage is characterized by a strong turnover marked by regional speciation and the appearance of many western Tethyan invaders. Although at the species level, the assemblage documents a strong provincialism, at the genus level, the high number of shared genera between Eastern Tethyan and Old World Tethyan realms begins a phase of long-term homogeneity of volutid assemblages from the Tethyan paleobiogeographic province.

The deep-water mollusks collected during the Marion Dufresne (MD55) expedition to the southeastern Brazilian coast in 1987 have been studied in several recent works. The present paper lists and diagnoses 19 species belonging to the vetigastropod families Calliostomatidae, Colloniidae, Margaritidae, and Solariellidae. A new species, Calliostoma valkuri sp. nov., is described. It is mainly characterized by a very short teleoconch I, with limits marked by conspicuous varices and sculpture consisting of 3 spiral threads; sculpture of the teleoconch II consisting of spiral cords with thorn-like projections; and the presence of two strongly marked cords on the median portion of the whorls. Based on the MD55 samples and complementary specimens from other expeditions, the following species have their geographical and/or bathymetrical range extended: Bathymophila euspira, Calliostoma gemmosum, Calliostoma rude, Callogaza watsoni, Gaza compta, Falsimargarita terespira, Homalopoma boffii, Lame...

The deep-water mollusks collected during the Marion Dufresne (MD55) expedition to the southeastern Brazilian coast in 1987 have been studied in several recent works. The present paper lists and diagnoses 19 species belonging to the vetigastropod families Calliostomatidae, Colloniidae, Margaritidae, and Solariellidae. A new species, Calliostoma valkuri sp. nov., is described. It is mainly characterized by a very short teleoconch I, with limits marked by conspicuous varices and sculpture consisting of 3 spiral threads; sculpture of the teleoconch II consisting of spiral cords with thorn-like projections; and the presence of two strongly marked cords on the median portion of the whorls. Based on the MD55 samples and complementary specimens from other expeditions, the following species have their geographical and/or bathymetrical range extended: Bathymophila euspira, Calliostoma gemmosum, Calliostoma rude, Callogaza watsoni, Gaza compta, Falsimargarita terespira, Homalopoma boffii, Lame...

Les Cancellariidae vivant le long de la cote ouest de l&#39;Afrique, autour des iles de l&#39;Atlantique central et dans la Mediterranee, sont etudies. Les vingt especes se repartissent comme suit: 3 Admetula, 1 Axelella, 2 Bivetiella, 4 Brocchinia, 1 Cancellaria s.1., 1 Nothoadmete, 1 Loxotaphrus, 2 Solatia, 1 Sveltia, 2 Tribia, et 2 Trigonostoma. Trigonostoma gofasi n. sp. se distingue de T. scala (Gmelin, 1791) n. comb., espece ouest-africaine, par sa protoconque multispirale, son ombilic plus evase, un callus columellaire lisse, des cotes axiales sur la rampe suturale n&#39;atteignant pas la suture, et l&#39;absence d&#39;un bourrelet siphonal ; et de T. goniostoma (Sowerby, 1832), espece ouest-americaine, par son ombilic plus ouvert, sa columelle plus deviee, et sa forme moins allongee. Une espece non-decrite de Solatia deja reconnue auparavant n&#39;est pas encore nommee faute de materiel suffisant. Le nom specifique dans la combinaison Bivetiella cancellata (Linnaeus, 1767) e...

Recent deep‐sea explorations in the South Pacific have documented around New Caledonia the most diverse fauna of gastropods of the family Volutomitridae anywhere in the world. Fourteen species (nine new, two remaining unnamed) are recorded, all essentially confined to the 250–750 m depth range. The high number of species in the New Caledonia region does not appear to be an effect of sampling intensity, but appears to result from four factors: regional spatial heterogeneity, frequency of hard substrates, syntopy, and a historical heritage shared with Australia and New Zealand, which until now ranked as the major centre of volutomitrid diversity. In the New Caledonia region, volutomitrids show a marked preference for hard bottoms and up to three species may co‐occur in the same dredge haul. Many species appear to have extremely narrow geographical distributions within the region (e.g. a single seamount or a single submerged plateau); conversely, Microvoluta joloensis, the only non‐endemic volutomitrid present in New Caledonia, ranges from the Mozambique Channel to Tonga.

Specimens of the genera Mathilda and Tuba from New Caledonia and the Loyalty Islands are studied, and compared with numerous other nominal mathildid species from the Indo-Pacific and Atlantic Oceans. Diversity is high in this region, with several species showing a much wider distribution in the lndo-Pacific than previously ascertained. Mathilda Semper, 1865 is used sensu lato, including Fimbriatella, Granulicharilda, Marhildona and Opimilda. From the study area thirteen species are diagnosed and compared, and several as yet unnamed forms that need further study are also discussed. Four new species are described, and Mathilda fusca (Okutani & Habe, 1981), previously placed in the turritellid genus Orectospira, is recognized as the largest extant member of the family Mathildidae. Tuba Lea, 1833 is also used sensu lato, including Gegania and Tubena, and is represented by two species (one described as new). Twelve Indo-Pacific species previously referred to as Mathildidae are removed from the family: Mathildona cookiana Dell, 1956 (Epitoniidae); Mathilda elegantula Angas, 1871 (Pyramidellidae ?); M. eurytima Melvill & Standen, 1896 (Cerithiidae); M. gracillima Melvill & Standen, 1901 (Capulidae); M. oppia Hedley, 1907 (Rissoidae); M. opulenta Hedley, 1907 (Cerithiidae); M. rosae Hedley, 1901 (Eulimidae); Eucharilda pleurorbis Laseron, 1951, and Opimilda protolineata Laseron, 1951 (Triphoridae); 0. porrigata Laseron, 1951 (Cerithiopsidae ?); Dunkeria pulchella A. Adams, 1860, and D. scabra A. Adams, 1860 (Epitoniidae)