First record of the Eocene pteropod Heliconoides nitens (Gastropoda: Thecosomata: Limacinidae) from the Pacific Basin (original) (raw)
Related papers
Pteropods (Mollusca, Euthecosomata) from the Early Eocene of Rotterdam (The Netherlands)
Scripta Geologica
A borehole was drilled at Rotterdam in 1955 as a demonstration during the E55 exhibition. Holoplanktonic molluscs (pteropods) were found to be present in the interval 504.5-655.0 m below rotary table (= RT). The upper sample of Middle Eocene (Lutetian) age yielded just a few unidentifiable limacinids. The section between 507.5-607.0 m, of Early Eocene (Ypresian) age, yielded poorly preserved pteropods and demonstrated that the complete interval belongs to pteropod zone 9. Apart from the most abundant species, Camptoceratops priscus, which is the index taxon of pteropod zone 9, the section yielded Heliconoides mercinensis and Limacina taylori, which are known to accompany the index species. Two further limacinid species are described as new to science, viz. Limacina erasmiana sp. nov. and L. guersi sp. nov., to date not known from elsewhere in the North Sea Basin. The occurrence of L. pygmaea in a restricted interval (569.0-574.0 m-RT) is remarkable; it is generally considered to be of Lutetian age, but also is found in the Ypresian of Gan, southwest France. Its occurrence in the E55 section is explained as a 'sealevel related molluscan plankton event', allowing species of oceanic distribution to enter the basin during sea level high stands, as was recently also demonstrated for several Oligocene pteropods.
Journal of Paleontology, 2013
Bathymodiolin mussels are a group of bivalves associated with deep-sea hydrothermal vents and other reducing deep-sea habitats, and they have a particularly rich early Cenozoic fossil record in western Washington State, U.S.A. Here we recognize six species from middle Eocene to latest Oligocene deep-water methane seep deposits in western Washington. Two of them are new: Vulcanidas? goederti from the middle Eocene Humptulips Formation and Bathymodiolus (sensu lato) satsopensis from the late Oligocene part of the Lincoln Creek Formation. Very similar to the latter but more elongate are specimens from the early Oligocene Jansen Creek Member of the Makah Formation and are identified as B. (s.l.) aff. satsopensis. Bathymodiolus (s.l.) inouei Amano and Jenkins, 2011 is reported from the Lincoln Creek Formation. Idas? olympicus Kiel and Goedert, 2007 was previously known from late Eocene to Oligocene whale and wood falls in western Washington and is here reported from Oligocene seep deposits of the Makah and Pysht Formations. Vulcanidas? goederti occurs at a seep deposit from a paleodepth possibly as great as 2000 m, suggesting that its living relative, Vulcanidas insolatus Cosel and Marshall, 2010, which lives at depths of only 150-500 m, is derived from a deepwater ancestor. The bathymodiolins in western Washington indicate that the group originated at least in the middle Eocene and underwent a first diversification in the late Eocene to Oligocene. Early ontogenetic shells of all fossil species investigated so far, including the middle Eocene Vulcanidas? goederti, reflect planktotrophic larval development indicating that this developmental mode is an ancestral trait of bathymodiolins.
Progress in Earth and Planetary Science
There is growing interest in the use of pteropods as potential archives of past changes in ocean chemistry. However, pteropods have rarely been used in studies of millennial-scale sedimentary records, especially in shallow-marine environments. This study obtained core data for the last 16 kyr from the Northwest Shelf of Australia (NWS). Changes in the carbonate saturation state were assessed based on the carbon isotope ratios (δ13C) of shells and the Limacina dissolution index (LDX) measured on the planktonic pteropod species Heliconoides inflatus. In addition, the calcification depth of the pteropods was estimated based on oxygen isotope values (δ18O) of pteropod shells and seawater. Our findings indicate that H. inflatus calcifies at a depth of 95–140 m. This confirms that H. inflatus records a shallow-marine signal on the NWS. The δ13C values of the pteropods record a notable decrease in carbonate ion concentrations after 8.5 ka. This decrease is associated with the post-glacial ...
Acta Palaeontologica Polonica
A total of 25 species of mollusks and crustaceans are reported from Oligocene seep deposits in the Talara Basin in northern Peru. Among these, 12 are identified to the species-level, including one new genus, six new species, and three new combinations. Pseudophopsis is introduced for medium-sized, elongate-oval kalenterid bivalves with a strong hinge plate and largely reduced hinge teeth, rough surface sculpture and lacking a pallial sinus. The new species include two bivalves, three gastropods, and one decapod crustacean: the protobranch bivalve Neilo altamirano and the vesicomyid bivalve Pleurophopsis talarensis; among the gastropods, the pyropeltid Pyropelta seca, the provannid Provanna pelada, and the hokkaidoconchid Ascheria salina; the new crustacean is the callianassid Eucalliax capsulasetaea. New combinations include the bivalves Conchocele tessaria, Lucinoma zapotalensis, and Pseudophopsis peruviana. Two species are shared with late Eocene to Oligocene seep faunas in Washington state, USA: Provanna antiqua and Colus sekiuensis; the Talara Basin fauna shares only genera, but no species with Oligocene seep fauna in other regions. Further noteworthy aspects of the molluscan fauna include the remarkable diversity of four limpet species, the oldest record of the cocculinid Coccopigya, and the youngest record of the largely seep-restricted genus Ascheria. Eucalliax is recorded for the first time from a seep and from the Oligocene.
Lethaia, 2009
: Late Palaeozoic mollusc reproduction: cephalopod egg-laying behavior and gastropod larval palaeobiology. Lethaia, Vol. 42, Faunal analysis of an oxygen-depleted marine Lower Carboniferous succession (Late Mississippian Ruddle Shale) suggests how some cephalopod taxa laid their eggs during the Late Palaeozoic. At the Ruddle Shale collecting site in Arkansas, USA, the facies and overall fauna suggest severe oxygen depletion at the sediment/water interface. The Ammonoidea, with their small egg size, were probably laid in suspended gelatinous eggfilled masses in the water column above the bottom or by attachment of the egg masses to floating debris. The ammonitella embryos developed within the suspended or attached egg mass; hatched individuals became part of the free-swimming plankton biota. Based on shell morphology the Bactritoidea probably followed the same reproductive pattern. Coiled nautiloids (the Nautilida) and most orthoconic nautiloids (mostly the Pseudorthocerida) probably did not lay their eggs in the mid water column or as floatant attachments. This conclusion is based on the fact that, with one exception, all shells recovered of these two nautiloid orders are well past hatching. Gastropods in the Ruddle Shale are very small and cannot be visually detected in the field. However, microgastropods are abundant in washed residues. Most specimens are much smaller than 1 mm. The largest caenogastropod specimen is 1.3 mm high. These caenogastropods represent isolated larval shells and a successful metamorphosis was impossible because of oxygen depletion on the bottom. Allegations that a size of more than 1 mm is too large for pelagic larvae are refuted by examples of planktotrophic larval shells of modern gastropods (more than 1 mm high) and Triassic caenogastropods (up to 2 mm high) from the Cassian Formation (Northern Italy, South Alps). Repository information is given for the type-material of the gastropod species Nuetzelina striata Bandel, 2002 and Anozyga arkansasensis Bandel, 2002 which were both erected based on specimens from the Ruddle Shale that were illustrated by Nützel & Mapes in 2001. h Ammonoids, bactritoids,
New and little known mollusks from ancient chemosynthetic environments
2010
Twelve mollusk species from late Jurassic to Oligocene cold seep deposits are described and illustrated. Nine of them are new, two have already been named, two new genera are introduced, and one species is described only in open nomenclature. Puncturella (sensu lato) mcleani sp. nov. and Fissurella (sensu lato) bipunctata Stanton, 1895 are the only confirmed fissurellids in fossil cold seeps. The sutilizonid Triassurella goederti sp. nov. is similar to the modern ventinhabiting Sutilizona and the Late Triassic shallow-water reef-inhabitant Triassurella carnica. A smooth, late Jurassic neritid is the oldest neritid from fossil seeps and probably represents an independent neritid radiation into the seep environment, without close phylogenetic connection to the modern Bathynerita. The four new abyssochrysoid caenogastropods Humptulipsia macsotayi, Hokkaidoconcha novacula, Paskentana anistratenkorum, and P. umbilicata significantly extend the stratigraphic and geographic ranges of these apparently seep-restricted genera. Four bivalves are described, including the new modiomorphid Caspiconcha rubani from the early Cretaceous and the new bathymodioline Bathymodiolus (s.l.) palmarensis from the Oligocene. Among the lucinids, the oldest seep-inhabiting lucinid (late Jurassic) is described as Beauvoisina carinata gen. et sp. nov.; the new genus Cubatea is introduced for an Oligocene lucinid from Cuba. It is suggested that Caspiconcha, Paskentana, and hokkaidoconchids constitute the core of a seeprestricted fauna that inhabited seeps worldwide from (at least) late Jurassic to early Cretaceous time. These taxa are, at the family level, phylogenetically unrelated to the modern vent and seep fauna.
Time-calibrated molecular phylogeny of pteropods
PloS one, 2017
Pteropods are a widespread group of holoplanktonic gastropod molluscs and are uniquely suitable for study of long-term evolutionary processes in the open ocean because they are the only living metazoan plankton with a good fossil record. Pteropods have been proposed as bioindicators to monitor the impacts of ocean acidification and in consequence have attracted considerable research interest, however, a robust evolutionary framework for the group is still lacking. Here we reconstruct their phylogenetic relationships and examine the evolutionary history of pteropods based on combined analyses of Cytochrome Oxidase I, 28S, and 18S ribosomal rRNA sequences and a molecular clock calibrated using fossils and the estimated timing of the formation of the Isthmus of Panama. Euthecosomes with uncoiled shells were monophyletic with Creseis as the earliest diverging lineage, estimated at 41-38 million years ago (mya). The coiled euthecosomes (Limacina, Heliconoides, Thielea) were not monophyle...