Monthly Archives: February 2013

Cuban land snails

Recently I received a copy of a paper on Cuban terrestrial snails by Maceira et al. (2011). It had been published in the journal ‘Gaia’, of which I had frankly not heard before. The paper gives an overview of the history of Cuban malacology, which now is by far the best studied place in the Neotropics related to malacohistory. The paper is in Spanish, but with an English abstract.

The land mollusc fauna, in Cuba, is represented by the subclass Prosobranchiata (476 species, 52 genera, 6 families) and the subclass Pulmonata (922 species, 103 genera, 27 families). In the present paper we rebuilt the history of Cuban Malacology during the period encompassed from January 4th, 1839 until May, 2010, with spot citations corresponding to 1684, 1774, 1780 and 1786, all of which summarizing 171 years of research regarding this branch of Science. Along centuries XVII and XVIII, a few Cuban species were discovered, all of them erroneously attributed to Italy and China. On the XIX century 132 new Cuban species were described as new to Science, also in this period it was published “Contribución a la fauna malacológica cubana”, the first catalog of Cuban mollusks written by Rafael Arango y Molina. On the 20th century, golden age to Cuban Malacology, they published some of the most important work monographs on Cuban mollusks of all times. A list of outstanding contributors´ names from 1900 to 1950 is the following: A. A. Welch, Abelardo Moreno, Carlos de la Torre, Carlos Guillermo Aguayo, Charles Ramsdem de la Torre, Henry A. Pilsby, Hortensia Sarasúa, J. Natenson, John Henderson, Luis Howel Rivero, L. Pequeño, M. K. Jacobson, M. Sánchez Roig, Miguel L. Jaume, Oscar Alcalde Ledón, Paul Bartsch, R. García Castañeda, R. P. Guitart, Víctor J. Rodríguez y William J. Clench. On the second half of the Century a new approach began to be made regarding the research goals and questions concerning this group of animals, also a new set of biologists´ names can be cited as most remarkable contributors to this subject: Alejandro Fernández Velásquez Alina Lomba, Antonio Mijail Pérez, Bernardo Reyes Tur, David Maceira, José Fernández Milera, Liana Bidart, José Espinosa, Jesús Ortea, Miguel Aangel Alfonso, Pastor Alayo Dalmau, R. Tadeo Pérez, Raúl Fernández Garcés and Vicente Berovides. It was found that the Isle of Youth has 75 infrageneric taxa. The most important higher taxa are Annulariidae with 18 species, Urocoptidae with 9 and Helicinidae gathering 8 species. Cuba exceeds to Jamaica in 835 species in total, 831 endemic species, 206 species of non pulmonated terrestrial mollusks and 678 of pulmonated. Cuba exceeds 847 species to La Española, 60 genera and 6 families, 224 species of terrestrial mollusks and 624 of Stylommatophora. In terrestrial pulmonated molluscs for Puerto Rico are recognized 150 species. The larger families were Subulinidae which has 12 species and 3 genera in Cuba than in Puerto Rico; Xanthonychidae with 48 species and 6 genera more in Cuba and Camaenidae 8 species more in Cuba and an equal number of genera in both islands.

The paper also gives a bibliography on the subject, and is therefore highly redundant with Breure & González (2010).

This paper put me on track of another one (Lauranzon et al., 2011), on the type material in the historical collections of Museo Historia Natural ‘Tomas Romay’, and Museo ‘Jorge Ramon Cuevas’. Both museums are localted in Santiago de Cuba resp. Baconao. In total 434 type specimens were recorded, belonging to the families Annularidae, Cerionidae, Megalomastomidae, Helicinidae, Orthalicidae and Urocoptidae. The material originated from the collections of Cleto Sanchez Falcon and Miguel L. Jaume.

This is an important contribution as it documents that these type species are still being preserved. Given the difficult circumstances in Cuba this is not obvious at all. The paper is, however, very concise and lacks important data which would be needed for further research. Besides the number of specimens and the locality and label information, no other useful data are presented and illustrations are totally absent. Nevertheless, in science all tiny steps help to make progress.

The third paper appeared in the same journal, Novitates Caribaea, which is annually issued by the Museo Historia Natural, Santo Domingo, Dominican Republic. It deals with two Cuban species and presents ecological data. The abstract reads:
The finding of individuals from the population of Cerion politum maisianum Pilsbry, 1902, cohabiting with individuals of Polymita brocheri (Gutiérrez, 1864) in one zone belonged to Paso de los Azules at Punta de Maisí, Guantánamo, after a research that was made in the area, it shows us the state that these species actually are. According to the proposal and applied scales P. brocheri and C. politum maisianum, both turned out Very abundant. The preferences on different substrates of these species are given too, finding the majority of the examples of P. brocheri at one height ≥ 0.50m and C. politum maisianum examples at one height < 0.25m, condition that makes possible its coexistence.

References:
Breure, A.S.H. & González, A. Guillén, 2010. Bibliography of Cuban terrestrial Mollusca, including related and biohistorical papers on Cuban malacology. Netherlands Centre for Biodiversity Naturalis, Leiden, Netherlands. 62 pp.

Lauranzon, B., Maceira, D. & Moran, M., 2011. Material tipo depositado en las collecciones malacologicas historicas “Cleto Sanchez Falcon” y “M.L. Jaume” en Santiago de Cuba, Cuba. – Novitates Caribaea 4: 34-44.

Maceira, D., Espinosa, J. & Pérez, A.M., 2011. Historia de la malacologia terrestre cubana, 1839-2010.Gaia 12: 1-48.


Suarez, A. & Fernandez, A., 2012. Subnicho estructural y densidad poblacional de Cerion politum maisianum y Polymita brocheri en Paso de los Azules, Maisi, Cuba.Novatitates Caribaea 5: 66-72.

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Photo of the day (141): Drymaeus

About two years ago David Robinson (USDA) sent me a picture for identification of a shell found in the Dominican Republic. He said it was collected by a local malacologist and was beyond doubt a Drymaeus species. Indeed, it appeared to me D. moussoni (Pfeiffer, 1853), a rare species which was described from “Santo Domingo”; this name, now the capital of the Dominican Republic, was in the 19th century also used to designate the island of Hispaniola. So in fact, it didn’t give much of clue about its locality.

Last year A. Espinosa (2012) published the photo in a paper reporting the finding of this species and unveiled the locality. Hitherto only collected in Haiti, she presented also details about the ecology. She found 48 individuals on three species of shrubs and trees, in association with Liguus virgineus. As the chance that this species still survives in the depleted Haitian nature seems approaching zero, the discovery of this healthy population is important for conservationists. Provided that it still surviving…

Reference:
Espinosa, A., 2012. Nueva poblacion de Drymaeus moussoni (Mollusca: Bulimulidae) en la Hispaniola. – Novitates Caribaea 5: 97-99. Available at http://mnhn.gov.do/publicaciones/novitatesno5.pdf

Venezuelan tepuis – their caves and biota

The Venezuelan tepuis have long been a mysterious place and geologists only recently have begun to explore the caves inside these mountains made up by sandstones. Some years ago geologists and speleologists from Czech and Slovakia set out to Chimantá massif, together with local counterparts. They explored the immense caves that are present and brought several novelties for science home. Among them some snails, collected on special request.

Now the scientific results have been compiled in a book: Venezuelan tepuis – their caves and biota (Aubrecht et al., 2012). Originally scheduled for end 2011, officially dated for 2012, it only now appears in 2013. Thanks to the determined editors, Roman Aubrecht and Jan Schögl, they succeeded in the end. A paper version of the book will appear “later (perhaps in March)“.
This book contains parts on Cave systems in Churí and Roraima tepuis, and Faunistical investigations of Pantepui biogeographical region. The chapter on the malacofauna is a review of all known species, with new data on the anatomy of some and phylogenetic results on Plekocheilus species.
My contribution on the malacofauna is slightly ‘outdated’ (so to speak); my recent paper published in Basteria (Breure, 2012) was written after the deadline for this book was closed. And another paper is in the pipeline. This subject remains intriguing for me…

References:
Aubrecht, R., Barrio-Amorés, C.L., Breure, A.S.H., Brewer-Carías, C., Derka, T., Fuentes-Ramos, O.A., Gregor, M., Kodada, J., Kovácik, L., Lánczos, T., Lee, N.M., Liscák, P., Schlögl, J., Smida, B. & Vlcek, L., 2012 [2013]. Venezuelan tepuis – their caves and biota. – Acta Geologica Slovaca, Monograph, Comenius University, Bratislava: pp. 1-168. Available at http://geopaleo.fns.uniba.sk/ageos/archive/monograph/aubrecht_et_al_2012_monograph.pdf (NB: 163 Mb).
Breure, A.S.H., 2012. Living in isolation: Plekocheilus (P.) philippei spec.nov. from Venezuelan Guayana (Gastropoda, Amphibulimidae). – Basteria 76: 101-106.

Bye bye Posterous

Some years ago I continued my blog – of which the old posts are still available on my website ashbreure.nl – to the weblog posting site Posterous. I thought: given the in-built features both convenient for you as reader as well as practical for me.

Some weeks ago I discovered that Posterous, the company being sold to Twitter, is just a quick bird, flying away with the winds. Out of the blue not being able to post any news, I was left quite stupefied. The only thing they did decently was offering the availability to back-up your blog and to download it.
It took me some time to make up my mind, whether to continue and find a new home for my blog or not. Finally I decided the pick WordPress, as they seemed to have a decent import facility for the blog file. So, here it is again, at breure.wordpress.com: Bram’s snailblog, on Neotropical snails and tidbits. I hope you continue to enjoy…

Modeling on Giant African Snail invasion

An Argentinan group of colleagues has elaborated the potential areas where the Giant African Snail (GAS) might occur or invade (Vogler et al., 2013). Using the same methodology as Borrero et al. (2009), they have detailed now the potential distribution areas for all South American countries. The abstract reads:

The best way to reduce problems related to invasive species is by preventing introductions into potentially susceptible areas. The purpose of this study was to create distribution models for the invasive gastropod Achatina fulica Bowdich, 1822 in South America in order to evaluate its potential geographic distribution and identify areas at potential risk. This mollusc, considered one of the 100 world’s worst invasive alien species, is the focus of intense concern due to its impact on agriculture, human health, and native fauna. We tested two commonly used ecological niche modeling methods: Genetic Algorithm for Rule-Set Prediction (GARP) and Maximum Entropy (MaxEnt). Models were run with occurrence points obtained from several sources, including the scientific literature, international databases, governmental reports and newspapers, WorldClim bioclimatic variables, and altitude. Models were evaluated with the threshold-independent Receiver Operating Characteristic (ROC) and Area Under the Curve (AUC). Both models had consistent performances with similar areas predicted as susceptible, including areas already affected and new potentially susceptible areas in both tropical and temperate regions of South America.

This new study is more detailed and much more elaborated than Borrero et al. (2009), and uses two modeling methods, (A) GARP and (B) Maxent, of which the latter is generally performing best in comparative studies. The relevance of presenting country maps for potential distribution of this species in each South American country is clear: the responsible authorities now have a handle to focus their attention to areas most under threat. Generally, the Amazon basin is most infected or theathened, but certain areas in Ecuador, Colombia and Venezuela are across the Andes but have already been invaded. The following table shows that none of the South American countries can escape to the threat of GAS, although there are gradual differences.

References:
Borrero F.J. et al., 2009. Into the Andes. Three new introductions of Lissachatina fulica (Gastropoda, Achatinidae) and its potential distribution in South America. – Tentacle 17: 6-8.
Vogler, R.E., Beltramino, A.A., Sede, M.M., Gutiérrez Gregoric, D.E., Nuñez, V. & Rumi, A., 2013. The Giant African Snail, Achatina fulica (Gastropoda: Achatinidae): using bioclimatic models to identify South American areas suspectible to invasion. – American Malacological Bulletin 31: 39-50.