Monthly Archives: June 2016

Reviving Galapagos snails

Under this short title as eye-catcher, Villanea et al. (2016) recently published about an improved method to apply ancient-DNA techniques to identify material obtained from empty shells. The full abstract reads as follows: “Snail shells represent an abundant source of information about the organisms that build them, which is particularly vital and relevant for species that are locally or globally extinct. Access to genetic information from snail shells can be valuable, yet previous protocols for extraction of DNA from empty shells have met with extremely low success rates, particularly from shells weathered from long-term exposure to environmental conditions. Here we present two simple protocols for the extraction and amplification of DNA from empty land snail shells from specimens of Galápagos endemic snails, including presumably extinct species. We processed 35 shells of the genus Naesiotus (Bulimulidae) from the Galápagos islands, some from species that have not been observed alive in the past 50 years. We amplified and sequenced short fragments (≤244 bp) of mitochondrial DNA (mtDNA) from 18 specimens. Our results indicate that the implementation of an ancient DNA extraction protocol and careful primer design to target short DNA fragments can result in successful recovery of mtDNA data from such specimens”. The crux is that the method seems to circumvent largely the PCR inhibitors that are co-extracted when using degraded shells. The resulting tree is given below.

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One of the co-authors wrote me “We are really excited about this approach as it will allow us to include rare and potentially extinct species to our considerations of the evolutionary history of the Naesiotus group”. Methodical seems the approach sound, although it remains vague what exactly the inhibitors are. Given the more laborious extractions during aDNA work, it seems to me that the PCR will remain the bottle-neck. With more PCRs needed, this will remain a relatively costly procedure.

Reference:
Villanea, F.A., Parent, C.E. & Kemp, B.M., 2016. Reviving Galapagos snails: ancient DNA extraction and amplification from shells of probably extinct Galapagos endemic land snails. – Journal of Molluscan Studies (early online access; doi: 10.1093/mollus/eyw011).

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Ecology of Costa Rican Drymaeus

Recently a very interesting paper has been published by Zaidett Barrientos (2016), describing the genitalia, mating behaviour and providing ecological data of the Costa Rican species Drymaeus tripictus (Albers, 1857).

The abstract reads “Very little is known about the ecology and biology of Drymaeus tripictus, an extremely rare and endemic land snail species from Costa Rican highlands. I studied the ecology and reproductive biology of D. tripictus from April 2009 through June 2010 in an old forest, a young forest and a Cupressus lusitanica plantation in central Costa Rica. Every three months I visited each habitat and collected specimens in 20 random sampling plots (3×3 m2 each). I observed the snail’s activity and microhabitat preference in the field, and in the laboratory I recorded high definition videos of its mating behavior and analyzed reproductive morphology with light microscopy. The snail is more abundant in the old forest (0.017 ind./m2) and prefers leaves with little epiphyllous cover (0-25 % cover, chi-square test, p <0.0001). During the dry season the snails become active between 20:00 pm and 8:00 am (chi-square = 22.65, df=3, p < 0.0001); they are inactive mainly during the afternoon (11:00 am to 16:59 pm). I found active individuals mostly on the upper side of leaves, where they feed (Chi-square =6.76, df=1, p = 0.0093). Mating is unilateral, by shell mounting, with cryptic phallus intromission and without role switching or multiple mating. Its reproductive system is morphologically similar to that of Drymaeus costari- censis. Mating behavior is as expected for snails with high-spired shells, except for the lack of role switching. The density of D. tripictus is low even when compared with other endangered bulimulids”.

Schermafbeelding 2016-06-22 om 12.27.02

Supplementary files on the journal’s website are supposed to be videos of the mating, but these were unavailable at the time of writing.

Reference:
Barrientos, Z., 2016. Reproductive system, mating behavior and basic ecology of an extremely rare tropical snail: Drymaeus tripictus (Stylommatophora: Bulimulidae). – Revista  de Biologia Tropical 64 (1): 55–68.

New paper

Today a new paper was published about Caribbean molluscs, viz. the land snail fauna of Saint Kitts and Nevis in the Lesser Antilles.

The abstract reads: “An overview of the land snail fauna of the Lesser Antillean islands of Saint Kitts and Nevis is given, based on data from literature and two recent surveys. There are 33 taxa listed, of which 26 are from Saint Kitts and 22 from Nevis. One taxon is described as new: Bulimulus ouallensis Breure and Hovestadt. Furthermore, the following taxa are recorded from these islands for the first time: Bulimulus diaphanus fraterculus (Potiez and Michaud, 1835), Obeliscus swiftianus (Pfeiffer, 1854), and Zonitoides arboreus (Say, 1817). Four taxa—Diplosolenodes sp., Pallifera sp., and two Succinea species—could only be identified to the genus level. Three taxa, previously thought to occur on the islands, are now removed from their faunal lists, due to inaccuracies of provenance of specimens or misidentifications. Finally, remarks are given on the distribution and conservation status of species collected during the surveys”.

Schermafbeelding 2016-06-14 om 18.26.58

Reference:
Breure, A.S.H., A. Hovestadt, A. Fields & D.G. Robinson. The land Mollusca of Saint Kitts and Nevis (Lesser Antilles), with description of a new species. — The Nautilus 130: 27–52.

More on Madrid

Nearly at the end of my visit in Madrid, it’s time to show a little more. The museum is in a relatively old building, but the exhibition part is nice (although without Dino’s ;-), and the exhibition even starts outside with an artistic interpretation of part of the museum’s collection. I have chosen to show you a snail of course…

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Ignoring the obvious errors in the name, it’s at least a way to give the public a preview of what’s inside.

Today I gave, as part of my Synthesys visit, a presentation. The topic was “Historical collections and ancient science networks”. See the PDF CCP_ancient science networks. Also a photographer came, so I suppose they want to show off their Synthesys visitors somehow; anyhow, below you see me with my host Rafael Araujo in the storage room of the terrestrial molluscs with part of the material collected by the Comisión Cientifica del Pacifico. All 230, earlier recognised lots have been revised, but on my way I also found a considerable number of additional lots, included some overlooked type material. In due time it will result in another manuscript.

Araujo y Bram_2

So, for several reasons it was a most enjoyable and productive stay…

 

A.C. (Dolf) van Bruggen (1929-2016)

My esteemed colleague and friend Dr A.C. (Dolf) van Bruggen passed away last Friday. This very sad news reached me while in Madrid, and it was more or less expected as his health situation was bad for the last couple of weeks.

I met Dolf first when I was a student, and he was also on the Committee during my PhD-graduation. Since that time we mostly met during meetings of the Netherlands Malacological Society as my career had taken another direction. However, when I re-started my research in 2008, Dolf warmly welcomed me back at the museum where he frequented his own room as a Honorary Associate.

When I visited him at home for what would be the last time, he was cheerful as always, and very keen to hear the latest malacological news. The last 1,5 years he did not visit the museum anymore, after he had been forced to leave the room in which he resided for so many years. Also the Netherlands Malacological Society meetings were no longer visited during the last years, but as always he kept himself busy with some editorial work for its journal ‘Basteria’.

Recently, together with Dai Herbert, we still had a joint publication, and I’m not sure if anything more was in the pipeline. A partial biography, list of new taxa and eponyms was published in a ‘Festschrift’ on the occasion of his 80th birthday in 2009. His list of publications, which had been compiled for this occasion, seems not to have survived on the museum’s website; so it would be nice to publish it formally.

When asked for, Dolf was happily prepared to give advice with his great knowledge of many subjects, which I always found useful to follow, but the most I will miss his nice and warm personality. My condoleances go to his wife Wenda van Bruggen-Gorter.

ACvB09

A great malacologist has gone…

More on Argentinian Bostryx

María José Miranda has recently published a new study on several Bostryx species from central western Argentina. As always, this is a thorough paper with lots of anatomical data.

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The abstract reads: “The genus Bostryx Troschel, 1847 is endemic to South America, extending from Ecuador to Chile and Argentina. The southernmost Argentinian species of the genus that inhabit San Luis, San Juan and Mendoza provinces, specially the pre-Andes, Andes and Sierras Pampeanas mountain ranges, were examined. This is the first time the anatomy of Bostryx pastorei (Holmberg, 1912), Bostryx reedi (Parodiz, 1947) and Bostryx strobeli (Parodiz, 1956) has been described. Bostryx cordillerae (Strobel, 1874) is re-described regarding shell and anatomy due to new morphological data. The main differences among the species examined are based on shell characters. The distribution of Bostryx mendozanus (Strobel, 1874) and Bostryx cuyanus (Pfeiffer, 1867), other species found in this region, was also discussed”.

As she cited my publication about the subfamily Bostrycinae (Breure, 2012), I feel entitled to correct a possible misinterpretation. From her text it gives the impression that I have a very restricted view of this subfamily, leaving out all species not listed in my 2012 paper. The contrary is true. Page 3 of my paper explicitly stated that the list presented is incomplete, and further research should show which other species belong to this monophyletic clade. As the shell shape may be very misleading, which is corroborated in Miranda’s paper, I invited further research using anatomical and molecular data. Miranda’s paper is a welcome contribution to this end, although she has not presented phylogenetic data which could supplement the available data in GenBank. Hence there is room for further additions…

References:
Breure, A.S.H., 2012. The status of the genus Bostryx Troschel, 1847, with description of a new subfamily (Mollusca, Gastropoda, Bulimulidae). – ZooKeys 216: 1-3.
Miranda, M.J., 2015. The genus Bosoryx in central western Argentina: anatomical and distributional description of four of its southernmost species (Gastropoda, Bulimulidae). – Iheringia, Zoologia 105: 484–498.