A ritual link to snail invaders

Vazquez et al. (2017) recently published interesting research related to invasions. Their abstract reads as follows “The giant African snail, Lissachatina fulica, is considered one of the most invasive species worldwide, acting as a crop pest and diseases vector. It was first detected in Cuba in 2014 and is dispersing throughout Havana. We mapped 34 sites in the vicinity of Havana to assess its spread and analysed ecological (forestation and humidity) and anthropogenic (pollution and religious sites) factors in relation to the presence/absence of the snails using multivariate correspondence analysis. There were 14 sites at which the snail was present and where religious rituals of the Yoruba creed, an African rooted religion, were observed. No other variables showed significant relationships. This indicates that the rituals may be a major factor in the dispersal of the snail in Havana and more widely in Cuba. In light of this an outreach program with key Yoruba leaders may help in slowing the dispersal of the snail within Cuba, once the threats posed by this species are known”.

Reading through their paper I noticed that there may be also a ritual origin of the introduction of this snail in Florida, while there are indications that something similar maybe at stake in Brazil. Perhaps time for an ethnobiological approach complementary to the usual eradication schemes? Eradication without taking the driving force away behind the spread of this snail may simply not be sufficient.

Reference:
Vazquez, A.,  Sanchez, J., Martinez, E. & Alba, A., 2017. Facilitated invasion of an overseas invader: human mediated settlement and expansion of the giant African snail, Lissachatina fulica, in Cuba. – Biological Invasions, 19 (1):1-4.

Interaction between alien and native species

Mirando & Pecora (2017) published an ecological study on the interaction between a native and an introduced species. “The Giant African Snail Achatina fulica is widely considered one of the most invasive species in the world. Megalobulimus paranaguensis is a snail endemic to the Brazilian Atlantic Rainforest. Data on possible interactions between A. fulica and terrestrial mollusc species are scarce. We tested whether the presence of A. fulica affects the behaviour of M. paranaguensis. We put three individuals of A. fulica and three individuals of M. paranaguensis in the same aquarium and quantified the time spent in seven behaviours, during three nights (n = 72 individuals for A. fulica and M. paranaguensis). We also tested the effect of sexual maturity, putting juvenile and adult individuals of both species in the same aquarium. We found behavioural differences between species, among individuals exposed to interspecific interactions and in interactions between these factors, but there was no difference in behaviour between juveniles and adults in the same species and between species. Achatina fulica changed its behaviour in interspecific interaction, becoming more active than usual, but M. paranaguensis did not change its behaviour in the presence of the alien species. Our results show that interspecific interaction has an effect on the behavioural patterns of the alien species, and the main factor negatively impacting Megalobulimus populations in Brazil is probably the non-specific control of A. fulica and the alteration and destruction of its habitats”.

This kind of studies, still rarely done, may become more important with the spread of introduced species (unfortunately too often happening). The study will be especially appealing to ecologists and conservationists.

Reference:
Miranda, M. & Pecora, I., 2017. Conservation implications of behavioural interactions between the Giant  African Snail and a Native Brazilian species. – Ethology Ecology and Evolution, 29 (3): 209-217.

Morelet and the Neotropics

Arthur Morelet (1809-1892) was a French amateur malacologist who has contributed much to malacology (nearly 100 publications, describing more than 700 taxa). He was one of the first malacologists who personally went on expedition to the Neotropics; a trip lasting more than a year during 1846-1848 which yielded nearly 150 new species collected on Cuba, and in Mexico and Guatemala. A few of these are illustrated below (scale: 5 mm).

The advantage of collecting in an unexplored area is indeed the reward to find many species new to science. But the legend above also shows one of the problems (possibly one of the least!) which Morelet faced: there was no Zoological Record or BHL mid-19th century, so there was a chance of introducing a name already used by someone else. Nevertheless, about 2/3 of the species described by Morelet from this expedition are still bearing his author name today.

In the 19th century not every author was able to give precise type localities; often they had to rely on information given by field collectors. So another advantage of collecting your own material: you knew where it had be found. Morelet, in many cases, gave (relatively) good locality data, but still described a number of species with a (relatively) imprecise locality; like “sylvis provinciae Vera-Paz”, a huge area.

As I had come across Morelet and his material for quite some years, I decided it was time to make an in-depth study of this man and his contributions to malacology. Since much of his type material has ended up in the London museum, Jonathan Ablett was willing to join me in this effort. And after more than 200 letters of Morelet became available, Cédric Audibert (Lyon) joined in as well. Together we are busy preparing a bio-bibliography with a list of taxa, illustrated with type material of as much taxa as possible. The transcription and translation of his correspondence will make it possible for the reader to get a much better idea of the life of a malacologist during the late 19th century. Currently we have located about 80% of his type material in several European and some American museums. The remaining taxa will be illustrated with reporductions from the original figures if these are available. Since Morelet started his career as a draftsman, he always paid special attention to the illustration of his papers.

To my surprise nobody has made an attempt to reconstruct the expedition of Morelet to the Neotropics, which brought him not only to the three countries mentioned above but also in Belize. Morelet was not only gifted with a special interest in malacology, but also in history and literature; his library had many travel accounts on its shelves. As Central America was largely unexplored in the 1840s, he published a few years after his taxonomic descriptions also a travel account of his own journey, aimed to a larger public, with many details on the geography and history of the areas visited. These two books allowed me, with some close reading, to reconstruct his trip.

One of the interesting things I discovered was the description of some species from areas, e.g. from eastern Cuba, which he apparently never visited. González Guillén (2014: 147) assumed that Morelet had confused the habours where his ship landed in eastern Cuba. However, from Morelet’s travel account it is clear that he never visited eastern Cuba. He must therefore have received the material from this area, on which he based his descriptions, from another person.

Our monograph is scheduled to appear during Spring 2018 as a book published by the Netherlands Malacological Society. The figures have been taken from a preliminary study which was just published (Breure, 2017).

References:
Breure, A.S.H., 2017. Een expeditie naar de Neotropen: reconstructie van Arthur Morelet’s reis naar Centraal Amerika, 1846-1848. – Spirula, 411: 4-11.[Dutch]
González Guillén, A., 2014. Polymita, the most beautiful land snail of the world. – [Miami]: Estévez & Associates, 359 pp.

Achatina fulica east of Andes in Ecuador

Goldyn et al. have just published a paper of which the abstract reads “[w]e are reporting the first locality of invasive giant African snail, Achatina (Lissachatina) fulica (Férussac, 1821) in the Ecuadorian Amazon. It was found present in 32 out of 50 urban sites studied. The abundance where present was relatively high when compared to literature from other parts of the world. The snails were found in aggregations, usually foraging — most often on dogs’ feces. Statistical analysis suggests a preference toward this source of alimentation. This is the first report of such preference in this species, which is highly significant considering the possible implications. Besides the threat posed by an invasive species to the invaluable ecosystems of the Amazon, the pathogens transferred by A. fulica combined with a high abundance of the species in an urban environment and its food preferences may constitute an important health hazard for local human populations”.

This is, however, not the first published occurrence east of the Andes in Ecuador. The same authors have published this, and additional data, before in Folia Malacologica last year. If not an oversight by the reviewers and editor, this so-called “first locality” has to be blamed to the authors.

But the fact as such (if we exclude the many Brazilian occurrences), unfortunately, was waiting just to happen. Hopefully the Ecuadorian authorities nowadays know how they should eradicate this pest before it becomes wide-spread in this area which contain many endemic species.

Reference:
Goldyn, B., et al., 2017. Urban ecology of invasive giant African snail Achatina fulica (Férussac) (Gastropoda: Achatinidae) on its first recorded sites in the Ecuadorian Amazon. – American Malacological Bulletin, 35: 59-64.

Champion shells

Ever heard of ‘champion shells’…? I had not, but since yesterday someone told me of ‘champion trees’ in England, I got the context… the biggest, largest. It must be a human fascination…;-)

Anyhow, I the most recent number of Shell-O-Gram, the newsletters from the Jacksonville Shell Club, I noticed an article by Harry Lee about a giant shell from Mexico.

“In the March-April SOG, a new species of Euglandina from southeastern Mexico was treated. It belonged to a truly remarkable group of carnivorous snails mostly from the highlands of Mexico and Central America – some of which exceeded four inches in height. Through the magic of the Internet, a concatenation of subsequent events led to the discovery of a truly remarkable mollusk shell belonging to a closely related species, also apparently limited to Mexico. The specimen figured above is believed to be the largest native terrestrial snail shell ever found in North America, which includes Central America.

Before the discovery of this leviathan, the largest known shell belonged to a congener, but it was not identified as to species (see sweepstakes tabulation on p. 9 taken mostly from the literature cited below). Now the sweepstakes winner is clearly Sr. Vinagrillo’s specimen. Olé!”.

Reference:
Lee, H.G., 2017. Euglandina sowerbyana (L. Pfeiffer, 1846) – a true champion shell. – The Shell-O-Gram, 58 (3): 8-9.

Photo of the day (173): Drymaeus

The group ‘Speurneuzen’ makes nearly every week a hike on the Island of Curaçao, usually to look for cultural-historical objects, but always to enjoy nature. This week they followed a new trail made by ‘Uniek Curaçao’ from Fort Kloof to Ascuncion. From their photo report I show a small batch of Drymaeus elongatus on a Wayaca tree.

The picture was made by Fred Chumaceiro.

Biosecurity officers alert!

On the “Mollusca” listserver the following newsitem was posted:

May I add another experience to it?

When Valentín Mogollón and I described a new species last year in our paper Synopsis…, viz. Thaumastus sumaqwayqu, I returned the three specimens (shells only) which served as paratypes to Peru.

Our museum staff, very well experienced in shipments of biological material, sent the material with registered mail addressed to Mogollón. And indeed, we were “very upset” when shortly after the package had been shipped, we learned that quarantaine officers in Lima had seized the package as there was a (new) form missing from the accompanying papers.

Not being able to import the type material into the country, we requested to have it returned. But to our astonishment this appeared impossible. For the return shipment too the same form about the ‘health’ of the material (shells only!) was needed…

A truly Catch-22 situation.

After some deliberation only one conclusion was possible: there was no way out and the specimens had to be destroyed. What indeed happened.