Monthly Archives: November 2016

Land snails as atmospheric carbon proxies

Macario et al. (2016) recently have shown that shells of selected terrestrial species can be used as alternative to charcoal for radiocarbon dating.

“In Brazilian archaeological shellmounds, many species of land snails are found abundantly distributed throughout the occupational layers, forming a contextualized set of samples within the sites and offering a potential alternative to the use of charcoal for radiocarbon dating analyses. In order to confirm the effectiveness of this alternative, one needs to prove that the mollusk shells reflect the atmospheric carbon isotopic concentration in the same way charcoal does. In this study, 18 terrestrial mollusk shells with known collection dates from 1948 to 2004 AD, around the nuclear bombs period, were radiocarbon dated. The obtained dates fit the SH1-2 bomb curve within less than 15 years range, showing that certain species from the Thaumastus and Megalobulimus genera are reliable representatives of the atmospheric carbon isotopic ratio and can, therefore, be used to date archaeological sites in South America”.


Macario, K.D. et al., 2016. The use of the terrestrial snails of the genera Megalobulimus and Thaumastus as representatives of the atmospheric carbon reservoir. – Scientific Reports 6: 27395. DOI: 10.1038/srep27395.

Dissertation on some Peruvian snails

This is not a new publication, but already from 2008. It is a dissertation of Samira Guevara, who graduated in 2005 in Hamburg, Germany under supervision of Prof.Dr Klaus Bandel and Dr Bernhard Hausdorf. The subject of her thesis was the systematic treatment of snails collected in and around three National Parks in Peru. As this dissertation falls into the ‘grey literature’ I pay some attention to it, despite not being very recently published. The thesis is in Spanish, with summaries in German and English.

Snails were collected in the vicinity of Moyobamba (Bosque de Alto Mayo), Tingo Maria (Parque Nacional Tingo Maria), and Cuzco (Parque Nacional Manu). In total 5000 specimens were collected, belonging to 40 families and 136 species. The thesis gives more details for the families Helicinidae (10 species), Ceresidae (3 species) and Bulimulidae (9 species).

In the family Helicinidae, three new species are described: Helicina (Concentrica) bandeli, H. (C.) peruensis, and Alcadia (Microalcadia) kasteli. As the thesis was formally published in 2008, all species should have as author “Guevara, 2008”. The following pictures provide photographs of the holotype of each species, together with the type locality and the depository mentioned in the legends (ZMH is Zoologisches Museum, Universität Hamburg):

schermafbeelding-2016-11-25-om-11-38-04 schermafbeelding-2016-11-25-om-11-38-45 schermafbeelding-2016-11-25-om-11-39-06

The type localities for Helicina (Concentricaperuensis respectively Alcadia (Microalcadiakasteli are: Dept. San Martin, Cataratas del Gera, 12 km SE Moyobamba, 500m, respectively Dept. San Martin, Cueva Huacharos de Palestina-Rioja, 44 km NW Moyobamba, 894 m.

From the nine species mentioned in the family Bulimulidae, I think three have been misidentified. Both Valentín Mogollón and I arrived at the same conclusions. We will report on these in a later stage.


Guevara, S., 2005 [2008]. Estudio taxonómico y systemático de las familias Helicinidae y Ceresidae (Mollusca: Gastropoda: Neritopsina) y el género Drymaeus (Gastropoda: Pulmonata: Bulimulidae), en tres zonas de la Reserva Amazónica de Perú. Thesis Universität Hamburg, 2005 (unpublished) / Berlin, Verlag im Internet, 2008.

Nicaraguan biodiversity

López et al. (2015) have added a paper on the poorly known malacolofauna of Nicaragua, in which they report on a study of land and freshwater snails in a nature reserve in southern Nicaragua. This lake and the surrounding area lies in a volcanic district, and their inventory totalled up to more than 14,000 specimens belonging to 77 species. They found five species that might be new to science, but didn’t describe these.


The paper includes two tables, one with the collected samples per family, the second with the species listed alphabetically.

López, A., Urcuyo, J. & Vega, G., 2015. Biodiversidad de la fauna malacológica en la laguna de Apoyo, Nicaragua. – Revista Encuentro, 102: 8-18.

José Willibaldo Thomé (1930–2016)

J.W. Thomé was born the 9th October 1930 in Estrela, Edo. Rio Grande do Sul, Brazil as son of German immigrants. He received his education in Porte Alegre and later continued his studies at the Zoological Institute, University of Münster, Germany with Prof. Bernhard Rensch. After returning to Brazil, he took his doctoral degree at the Pontificia Universidade Católica (PUC) in Porto Alegre.


He was a renown specialist in the slug family Veronicellidae, and many students and a number of doctoral fellows studied with him after he became a Professor of Zoology at PUC. He was director of the natural history museum in Porto Alegre, and served in many public functions (a.o. for the Brazilian Societies of Malacology and of Zoology).

He passed away on the 29 June 2016.

Engels, W., 2016. In memoriam José Willibaldo Thomé (9 October 1930-29 June 2016). – Studies on Neotropical Fauna and Environment 51: 242–243.

Snails in birds’ nests

Already published for a while, but just arrived at our library in print: a paper by Miquel et al. (2015) describing the results of studying the nests of birds in Argentine on the content of shells and snails. It formed part of a larger study related to other invertebrates as well from the same source.

The abstract reads as follows: Bird’s nests are specialized habitats that are inhabited by a diverse suite of invertebrates, such as insects, spiders, pseudoscorpions, and ticks. This study presents a list of gastropods found in birds’ nests from Argentina for the first time. A total of 138 specimens of gastropods, belonging to 11 species, 10 genera and 8 families of snails were present in the nests of 42 birds from 6 families in 6 provinces in Argentina. Fifty eight specimens of the snail Pupisoma latens of different sizes were found alive in a nest, representing a new habitat for this species, which has been previously described from the aerial parts of trees. The remaining species were represented by dead specimens (fragments or empty shells), which can be tentatively attributed to bird diets, Among these, the most abundant species were Bulimulus bonariensis bonariensis and Succinea rneridionalis, both as pre-adults. The nests Anumbius annumbi and Furnarius rufus from the province of Buenos Aires had the highest number of specimens. Freshwater snails (Heleobia parchappii, Biomphalaria sp., and Drepanotrema sp.) comprised 13% of the snail species found.


The paper ends with an appendix showing previous references from literature on predation from snails by birds.

Miquel, S.E., Turienzo, P. & Di Iorio, O.R. 2015. Gastropod species found in birds’ nests from Argentina. Revista del Museo Argentino de Ciencias Naturales (n.s.) 17: 87–96.


Photo of the day (168): Neopetraeus

It has been a while ago that I received some interesting pictures of living snails (last post here), but today I have some photos to share which show different Neopetraeus species from Peru. The fist one is Neopetraeus tessellatus (Shuttleworth, 1852) from Huaracpampa, Cascapara, Yungay, Ancash, 3000 m.


The second is N. cremnobates H.B. Baker, 1963, from Kiman Ayllu, Cañón del Pato, Ancash, 1800 m.


Both photographs with accompanying identifications were sent by Valentín Mogollón (Lima), and are here thankfully acknowledged.

New preprint on science networks

Reconstructing historical science networks can be important for understanding the context of the historical core collection in natural history museums. For the reconstruction of such networks up till now one has to rely on correspondence between scientists in archives. These archives are very scarce and often have been lost or destroyed in the past. In taxonomy a proxy may be available in the form of new taxa described as eponyms for contacts of an author. This has been tested with some malacologists from the 19th/early 20th century for which data on their contacts are available, either as correspondence archive or by a re-construction of their network from different sources.

The resulting paper was just published as a preprint:



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.


“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.

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.

Achatina widespread in Ecuador

Several years ago the first introduction was reported of Achatina fulica in Ecuador. Goldyn et al. (2016) now have made a survey of its occurrence in the country, where it appears to be widespread.


“Distribution data on Achatina fulica Bowdich were obtained from pest control agencies and from a survey of potential localities randomly distributed in all provinces of Ecuador. Among the total of 1,236 localities, 1,065 (86.2%) held populations of the species. The snail was found to spread much faster than predicted and was present in areas not previously suspected to be under the risk of invasion. The most endangered and infested areas were the coastal and Amazonian regions of the country. According to the pest control reports from government agencies, A. fulica most often affected plantations of cocoa (24.8% of localities), plantain (11.8%) and banana (11.2%), but was also known to forage on 56 other species of cultivated plants. The survey of likely habitats in random localities showed a high infestation rate; urban and ruderal sites turned out to be important but largely neglected dispersal hotspots for the species. Regular observations on two populations in the city of Puyo (Pastaza province, Amazonia) showed that the growth rate and population density were high: reaching adult size took on average four weeks”.

Goldyn, B. et al., 2016. Notes on the distribution and invasion potential of Achatina fulica Bowdich, 1822 (Gastropoda: Pulmonata: Achatinidae) in Ecuador. – Folia Malacologica, 24 (2):85–90.