Tag Archives: vertiginidae

New fossil land shells from Patagonia

Miquel & Rodriguez (2015 [2016]) published a new paper on fossil shells from Miocene deposits in Patagonia, Argentina. Among them four new species, of which one is placed in a new genus.

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“A remarkable fossil assemblage composed of five gastropod taxa is described from the Early Miocene of Santa Cruz (Patagonia, Argentina) in southernmost South America. The assemblage includes extinct and living genera South America, and on geographic distributions and represent background new information on spatial and across time distributions as well as identification of new taxa. A new taxon, Patagocharopa enigmatica n. gen. n. sp., is tentatively assigned to Charopidae. Gastrocopta patagonica n. sp. (Vertiginidae) represents the oldest record of Gastrocopta in Argentina and the southernmost record for the Americas. Punctum patagonicum n. sp. (Punctidae) represents the first record of Punctum for continental South America, and characterized by a protoconch with traces of axial costulae and a teleoconch with strong radial ribs. Zilchogyra miocenica n. sp. is the first Miocene record of the charopid genus Zilchogyra. Fragments of a possible Scolodonta (Scolodontidae) are recorded. Overall, the assemblage represents an important and useful paleoenvironmental tool. This fauna suggests that a more temperate and humid environment than today—with a more dense vegetation cover—was prevalent at this site during the Early Miocene”.

Although the paper appeared in the September 2015 issue of the Journal of Paleontology, the actual publication date seems 2016. In the PDF I received it says “Published online: 22 March 2016”, while also the copyright is from this year. As new taxa are introduced in this paper, this is relevant information.

Reference:
Miquel, S.E. & Rodriguez, P.E., 2015 [2016]. A novel late Early Miocene assemblage of terrestrial gastropods from Santa Cruz (Patagonia, Argentina). – Journal of Paleontology, 89(5): 748-761.

Microsnails from Trinidad Island

Luiz Simone has posted several recent papers, and one of them has not yet been mentioned in this blog: Cunha et al. (2015) reported on the terrestrial microsnails collected by the Marion Dufresne Expedition in 1987 at Trindade Island, Brazil.

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No new species are described in this paper, but it is good to have this report on the often overlooked part of the malacofauna, especially from this oceanic island.

Reference:
Cunha, C.M., Salvador, R.B. & Simone, L.R.L., 2015. The terrestrial microgastropods of Trindade Island, Brazil. – Spixiana 38: 139–143.

New fossil species from Argentina

Miquel & Rodriguez (2016) describe a fossil fauna found in southern Patagania with an interesting composition. One new genus and four new species are described.

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The abstract is: “A remarkable fossil assemblage composed of five gastropod taxa is described from the Early Miocene of Santa Cruz (Patagonia, Argentina) in southernmost South America. The assemblage includes extinct and living genera South America, and on geographic distributions and represent background new information on spatial and across time distributions as well as identification of new taxa. A new taxon, Patagocharopa enigmatica n. gen. n. sp., is tentatively assigned to Charopidae. Gastrocopta patagonica n. sp. (Vertiginidae) represents the oldest record of Gastrocopta in Argentina and the southernmost record for the Americas. Punctum patagonicum n. sp. (Punctidae) represents the first record of Punctum for continental South America, and characterized by a protoconch with traces of axial costulae and a teleoconch with strong radial ribs. Zilchogyra miocenica n. sp. is the first Miocene record of the charopid genus Zilchogyra. Fragments of a possible Scolodonta (Scolodontidae) are recorded. Overall, the assemblage represents an important and useful paleoenvironmental tool. This fauna suggests that a more temperate and humid environment than today—with a more dense vegetation cover—was prevalent at this site during the Early Miocene”.

MiquelRodriguez7

Reference:
Miquel, S.E. & Rodriguez, P.E., 2016. A novel late Early Miocene assemblage of terrestrial gastropods from Santa Cruz (Patagonia, Argentina). — Journal of Paleontology X: 1–14 (advance access).

New species from Juan Fernandez Archipelago

Miquel & Araya (2015) recently published on new shells from the Juan Fernández Archipelago off the coast of Chile. This is the first addition since nearly a century ago. One species is new described, Neoparyphantoplsis crusoeana gen.n., sp.n.; one replacement name is introduced (Tornatellina juanfernandeziana), and five species are re-described.

MiquelAraya

Reference:
Miquel, S.E. & Araya, J.F., 2015. New records of terrestrial mollusks of the Juan Fernández Archipelago (Chile), with the description of a new genus and species of Charopidae. Archie für Molluskenkunde 144: 155-167.

Vertiginidae

Vertiginid land snails are tiny and constitute a tiny (but yet ill-studied) group of the Neotropical fauna. Apart from a monograph by Pilsbry in his Manual of Conchology, hardly any recent studies are known on this faunal element. For the Nearctic vertiginids Jeff Nekola has done much work and he has just published a note on the supraspecific taxonomy of the family (Nekola & Coles, 2016).

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A detailed phylogenetic study revealed that there are two clades, the Vertiginidae and Nesopupinae. The latter comprising tropical species. The paper discusses the use of genetical markers, and the interpretation of the results in the light of the number of taxa included in a family. The authors plead for a reconsideration of supraspecific concepts within the Orthurethra.

Reference:
Nekola, J.C. & Coles, B.F. Supraspecific taxonomy in the Vertiginidae (Gastropoda: Stylommatophora). – Journal of Molluscan Studies 82: 208–212.

A new minute Jamaican snail

Jeff Nekola and Gary Rosenberg have just a joint paper out about a new vertiginid snail from Jamaica. One of the authors well-known for his studies of Vertiginidae, the other for his database on the Jamaican malacofauna; this paper seems to be a perfect blend of expertise.

Vertigo marciae, a new species of gastropod mollusk (Pupilloidea: Vertiginidae), is described from Jamaica. This species is known in the Recent fauna only from John Crow Peak in the Blue
Mountains, but also occurs as a Pleistocene fossil at Red Hills Road Cave. Vertigo marciae has been confused with V. gouldii, but differs by its smaller shell size, lack of distinct shell striation, lack of an angular lamella, and presence of a flared aperture base. DNA sequence analyses document that V. marciae possesses unique mtDNA and nDNA sequences and is most closely allied with Vertigo alabamensis, V. hebardi, and V. oscariana. This group of species comprises a highly supported clade whose members are limited either to the Caribbean or the southeastern USA.

The authors suggest on the basis of their data a relict status for this endemic species, which nevertheless could also be looked for at other islands in the Caribbean in suitable habitat and altitudes. They postulate, on the basis of their molecular research, that long distance dispersal might be involved in this case.

Reference:
Nekola, J.C. & Rosenberg, G. (2013). Vertigo marciae (Gastropoda: Vertiginidae), a new land snail from Jamaica. – The Nautilus 127: 107–114.