Cancellaria

Abstract: Two generic names, Bivetia and Ventrilia, that have been misunderstood and out of use are discussed. One new generic name, Agatrix, is proposed and Cancellaria depressa Dall, a preoccupied specific name, is replaced.

Abstract: Grateloup (1827, 1832, 1847) described and illustrated numerous species of Cancellariidae from the Miocene of Landes (SW Aquitaine, France). A complete revision of his collection of Cancellariidae is presented here; about 80 registered specimens belonging to this familly are discussed. Geographic localities and stratigraphy of each species are discussed. An attempt of generic assignment is made for each taxon. We confirm the validity of the genus Gulia Jousseaume, 1887 and we complete its diagnosis; its differences from Ventrilia Jousseaume, 1887 are specified. Out of 32 figures published in 1847, only three (perhaps four) specimens seem to be missing. As a whole, one holotype by monotypy is present and we have found 16 specimens designated (here or previously) as lectotypes of 20 available taxa of the species-group (e.g., varieties with subspecific rank), created by the author or by subsequent authors; all are illustrated here. Twenty-two paralectotypes are also listed. The following species described by Grateloup are considered valid: Gulia deshayesana, Aneurystoma dufourii, Coptostoma (s.l.) laurensii, Bivetiella stromboides, Scalptia (s.1l) spinosa (senior synonym of S. (s.l.) spinifera), whereas Cancellaria westziana is considered a morph of Gulia acutangula. Moreover, two taxa are considered nomina dubia (Cancellaria papyracea, Cancellaria varicosa var. subumbilicata). The type specimens of some other valid species, created by posterior authors, are present in the Grateloup collection and are illustrated in this revision, e.g., Bivetiella subcancellata, Calcarata subhirta, ?Genus subsuturale, Sveltia salbriacensis. On the other hand, few other taxa created also from specimens illustrated by Grateloup are not considered valid, such as Cancellaria subvaricosa (nomen dubium), C. gratte-loupi (synonymous with Gulia acutangula), C. battersbyi (synonymous with Calcarata subhirta). Finally, one species described by Grateloup from the Rupelian (Fusus thorei') may belong to the genus Loxotaphrus.

Abstract: This is the first description of gastropod family Cancellariidae from the Lower Pliocene Cerro Negro Member of the Cubagua Formation from the Island of Cubagua, Venezuela. These deposits hold a rich and varied fauna of cancellariids, comprising at least nine species, plus a group which may contain more than one species, including two new taxa; Cancellaria (Cancellaria) capeloi nov. sp. and Cancellaria (Massyla) cubaguaensis nov. sp. Two new species are also described for the Lower Miocene Cantaure Formation of mainland Venezuela; Cancellaria (Bivetiella) lugogonzalezorum nov. sp., and Cancellaria (Bivetopsia) herberti nov. sp., increasing the number of cancellariids known from the Cantaure beds to 14. Cancellaria (Pyruclia) diadela Woodring, 1970 is here considered a junior synonym of Cancellaria (Pyruclia) scheibei Anderson, 1929. Ventrilia kissimmeensis Petuch, 1994 is here considered a synonym of Trigonostoma (Ventrilia) rucksorum (Petuch, 1994), as first revisers the latter name is chosen, the holotype of which is more characteristic of the species. The composition of the Neogene southern Caribbean cancellarid fauna is strongly paciphile, with most of the subgenera now restricted to the eastern Pacific. The Caribbean cancellariid fauna suffered a severe impoverishment following the uplift of the Panama Isthmus and closure of the Central American seaway, with only Cancellaria (s. s.) and Cancellaria (Ventrilia) of the larger-shelled taxa present in the Recent faunas.

Abstract: Author(s): Groves, Lindsey T; Squires, Richard L | Abstract: This checklist is a sequel to the one published by A Myra Keen and Herdis Bentson in 1944 and is an alphabetical listing of California marine Paleogene–Neogene mollusk species or subspecies described and/or figured in the published literature spanning the interval of 1944 through 2020 The original data are given for each species and subspecies of bivalves, gastropods, chitons (polyplacophorans), scaphopods, and cephalopods Where detected, formation names, ages, taxonomy, systematics, and specimen disposition were corrected A total of 559 genera and 1,698 species/subspecies were tabulated, with the bivalves and gastropods being the most abundant taxa Bivalve and gastropod diversity steadily built up during the Paleocene, nearly doubled during the Eocene warm time, declined greatly during the cool time of the Oligocene, rebounded to its highest peak in the Miocene and then declined slightly during the Pliocene The other classes represented only minor faunal components Chitons were only reported from the Pliocene, and cephalopods had their highest diversity during the Paleocene and Eocene Bivalve genera having the highest diversity are: Glycymeris, Macoma, Mactromeris, Nuculana, and Tellina Gastropod genera having the highest diversity are Cancellaria and Turritella It is very likely that the Turritella species/subspecies complex has been significantly overnamed The high point of research productivity of published reports on California Paleogene-Neogene mollusks was in 1990–1994, and a significant decline occurred in 1995–1996, following the closure of the Menlo Park USGS Paleontology and Stratigraphy facility An overall decline in productivity has continued, with noticeable upticks in 2003 and in recent years