Tag Archives: conservation

Molluscs in the news

Two news items came to my attention today. The first has been taken from the Conch-L list and is about conservation of Florida land snails. “Florida Fish and Wildlife [Conservation Commission] has just sent out a posting regarding endangered and threatened species. There are two proposed rulings on Tree snails. The one  is Liguus and the other is Orthalicus. Here is the Liguus and other species  link. http://myfwc.com/wildlifehabitats/imperiled/species-action-plans/”. Only Liguus fasciatus is mentioned, together with more than 50 species of other phyla.

Liguus Florida

The ‘Science in the news’ site had an item on natural history museums and how these institutions, behind the scenes, are centers of cutting-edge research. One example is the recent discovery of a Plekocheilus species, collected back in the 1800s. More brushing off the dust than cutting the edge, but anyway…


Extinction of land snails

My gut feeling about the IUCN Red List, the stringent and bureaucratic procedure involved, and the few land snails listed on it, have given me an uneasy feeling for quite some years. Now Régnier et al. (2015) have published a study in which they offer an alternative approach, viz. with a mixture of a model study and expert opinions.

Their abstract is brief: “Since the 1980s, many have suggested we are in the midst of a massive extinction crisis, yet only 799 (0.04%) of the 1.9 million known recent species are recorded as extinct, questioning the reality of the crisis. This low figure is due to the fact that the status of very few invertebrates, which represent the bulk of biodiversity, have been evaluated. Here we show, based on extrapolation from a random sample of land snail species via two independent approaches, that we may already have lost 7% (130,000 extinctions) of the species on Earth. However, this loss is masked by the emphasis on terrestrial vertebrates, the target of most conservation actions. Projections of species extinction rates are controversial because invertebrates are essentially excluded from these scenarios. Invertebrates can and must be assessed if we are to obtain a more realistic picture of the sixth extinction crisis”. But their summarizing figure shows the following picture:

Schermafbeelding 2015-06-15 om 16.03.46

From their discussion I derive the following quotes: “The current Red List underestimates the actual number of extinct and threatened invertebrate species: there are almost seven times as many extinctions in our sample as would have been listed following the IUCN criteria, and we suggest that discrepancies of this order of magnitude, or greater, given that mollusks are one of the better known invertebrate groups, should be expected for other invertebrate groups. (…) a number of studies and our own work suggest that invertebrate extinctions are mostly overlooked: we suggest that we have probably already lost 7% of described living species of the world. On oceanic islands, there is evidence that this percentage is much higher”. This is really alarming!

Their method involved a random selection of taxa that have been assessed. For the Neotropical realm the following species were involved: Amphistemma pilsbryanum, Arangia aequatoris, Bostryx apertus, Bostryx baeri, Bostryx dentaxis, Bostryx gayi, Bostryx haasi, Brachypodella collaris, Bulimulus erectus, Bulimulus inermis, Callocoptis vesperalis, Capillacea angustior guamaensis, Cochlodinella variegata, Dentellaria chemnitziana, Drymaeus albolabiatus, Drymaeus chaperi, Drymaeus combinai, Drymaeus icterostomus, Drymaeus mexicanus, Drymaeus picturataEucalodium moussonianum, Eurytus ameghinoi, Eurytus glandiformis, Eurytus pirriensis, Gongylostomella fortis, Guestieria martinida, Hispaniolana gigantea, Labyrinthus stolzmanni, Leiostracus coxiranus, Leiostracus spiritualis, Liparotes obesulus, Liparotes obesulus obesus, Lyobasis binneyi, Martirelix huertai, Obeliscus pattalus, Plagioptycha duclosiana abacoensis, Plekocheilus appuni, Praticolella berlandieriana, Radiodiscus ditzleri, Stenostylus meleagris, Streptostyla chiriquiana, Streptostyla flavescens boucardi, Streptostyla irrigua, Streptostyla potosiana, Thaumastus integer, Thaumastus yanamensis, Torrecoptis polita, Trilamellaxis parallela culebrensis, Urocoptis producta, Varicella angiostoma ingallsiana, Zachrysia auricoma. Species that were rated as ‘probably extinct’ in the model assessment are printed in bold. Both in the model and the expert approach the number of species that are qualified as ‘unable resp. not possible to assess’ is relatively high. So the lack of knowledge about the conservation status of land molluscs is still at an alarming level. Given the methodology used this is also a pregnant result of this important study.

Régnier, C., Achaz, G., Lambert, A., Cowie, R., Bouchet, P. & Fontaine, B., 2015. Mass extinction in poorly known taxa. – Proceedings of the National Academy of Sciences of the United States of America. Published online before printJune 8, 2015, doi:10.1073/pnas.1502350112  (see Full Text (PDF)).

New issue of Tentacle

Robert Cowie and his co-editors have succeeded to publish a new issue of Tentacle, the IUCN/ SSC Newsletter that appears annually. There are several papers in this issue relevant to Neotropical malacology.

Salvador & Simone report on a presumably new Leiostracus species from Minas Gerais, which may be extinct as the small patch of rainforest where it was found a few years ago has been cleared meanwhile. The variation in colour pattern observed in their material is, despite their remark of being “extremely variable”, not uncommon in arboreal species like Leiostracus, Drymaeus and other genera in the superfamily.

Schermafbeelding 2015-02-18 om 12.11.52

Agudo-Padrón & Luz report on a nursery project for Megalobulimus paranaguensis (Pilsbry & Ihering, 1900) in the city of Joinville (Santa Catarina). The first author, in a separate note, also on a salvage effort for a small population of Drymaeus (Mesembrinus) interpunctus (Martens, 1887). In a third note, he draws attention to the precarious official conservation status for mollusks in the States of Santa Catarina and Rio Grande do Sul, Brazil.

Suarez & Martínez report on the finding of a new population of Cerion tridentatum rocai Clench & Aguayo, 1953, on the Itabo River bank, in Boca Ciega, Havana, Cuba, approximately 4 km west of the type locality.

Schermafbeelding 2015-02-18 om 12.19.52

Fernández et al. provide data on rock dwelling species at risk due to recreational developments in Holguín, Cuba. Given the recent political changes this risk may turn out to devastate other snail populations along the Cuban coast in the time to come.

Simone draws attention to the recently described Adelopoma species from a park in Sao Paulo (see also here).

In three separate notes, Herrera reports on snails from the Island of Youth, Cuba (= Isla de la Juventus, formerly Isla de Pinas). One with a new locality record for a colour variation of Liguus fasciatus, one with a new locality for Priotrochatella stellata, and the last one on conservation issues in the Sierra de las Casas.

Schermafbeelding 2015-02-18 om 13.12.23

Santos and a suite of co-authors finally devote two pages on their efforts to update the list of endangered non-marine molluscs in Brazil. The new list features eight land snail species.

Comparing these papers with previous issues, it may be noted that the diversity of authors and topics (Brazilian and Cuban land snails) is diminishing. The complete issue is available online at: http://www.hawaii.edu/cowielab/Tentacle/Tentacle_23.pdf

AGUDO-PADRÓN, A.I., 2015a. Small actions making big differences: rescue of small native arboreal snails in an urban area of Florianópolis, Santa Catarina State, Central Southern Brasil. – Tentacle 23: 11-12.
AGUDO-PADRÓN, A.I., 2015b. The precarious official conservation status of molluscs in the States of Santa Catarina and Rio Grande do Sul, Southern Brasil. – Tentacle 23: 19-20.
AGUDO-PADRÓN, A.I. & LUZ, J.S. da., 2015. Active conservation of threatened indigenous land gastropods in the urban area of Joinville, Santa Catarina State, Central Southern Brasil. – Tentacle 23: 9-10.
FERNANDEZ, A., SUAREZ, A. & FRANKE, S., 2015. New records of rock dwelling mooluscs at risk from tourist developments on the coastal zone of Pesquepo Nuevo, Holguin, Cuba – Tentacle 23:  13-15.
HERRERA, J., 2015a. New localities for Liguus fasciatus (Müller, 1774) from the Island of Youth, Cuba. – Tentacle 23: 15-16.
HERRERA, J., 2015b. New locality for Priotrochatella stellata (Gastropoda: Helicinidae) from the Island of Youth, Cuba. – Tentacle 23: 20-21.
HERRERA, J., 2015c. Land snails of Suerra de las Casas protected area (Island of Youth, Cuba) and their conservation problems. – Tentacle 23: 23-24.
SALVADOR, R.B. & SIMONE, L.R.L., 2015. The discovery and possible extinction of a Leiostracus land snail in Southeastern Brasil. – Tentacle 23: 7-9.
SANTOS, S.B. dos et al., 2015. Observations on the review of the list of endangered non-marine molluscs of Brasil. – Tentacle 23: 26-28.
SIMONE, L.R.L., 2015. A new species discovered in an urban park within the third largest city in the world. – Tentacle 23: 18-19.
SUAREZ, A. & MARTINEZ, J., 2015. New data on Cerion tridentatum rocai, locally endemic to Boca Ciega, La Habana, Cuba. – Tentacle 23: 10-11.

Polymita: a new book

For those who have ever wanted to see the astonishing colour diversity in Cuban tree snails of the genus Polymita, there is good news. After a very long and complicated process recently the new book by Adrián González finally appeared. It presents hundreds of colourful photographs of the six Polymita species and their natural environment, plus backgrounds on its malacohistory and the urging conservation issues for these over-hunted gems.


González Guillén, A., 2014. Polymita, the most beautiful land snail of the world. Carlos M. Estevez & Associates, Miami, 359 pp. (More info at the publisher: cecon14@aol.com)

Tentacle 22

Robert Cowie just released the annual number of Tentacle; this journal on molluscs conservation issues has reached now issue 22.


Regarding the Neotropical realm contributions are made by some authors that regularly use Tentacle as outlet. Agudo Padrón & Souza da Luz report briefly on a study about conservation of non-marine molluscs in remaining urban forests. In such a remnant in Florianópolis they found 15 native species and 9 alien ones. The first author also briefly reports on richness and regional distribution within the state of Santa Catarina in a second article.

The announcement of a consulting process together with experts to evaluate the extinction risk of non-marine molluscs in Brazil by  Santos & Carvalho; the evaluating workshop is scheduled for September 2014.

Santos, Oliveira & Vasconcelos report on ecological research in the Atlantic Forest of Ilha Grande, Brazil. This is part of a larger research programme spanning all Brazilian biomes, and the first to include land and freshwater snails.

Maceira et al. contribute to this issue with a note “Molluscs and their conservation problems in the San Miguel de Parada Faunal Refuge, eastern Cuba”. Four terrestrial species are reproted, of which two exotic species.

The entire issue can be found here: http://www.hawaii.edu/cowielab/issues.htm

An elegant U-loop?

Invasive species are a well-documented when they are discovered in countries with good monitoring systems. However, in some instances these ‘hidden secrets’ of economic liberalisation and globalisation stay under the radar of authorities and scientists.

David Robinson kindly sent an example of this when showing me these pictures.


This is a Bulimulus species, possibly B. sporadicus (d’Orbigny, 1835); the specimen is not fully grown.

At first I couldn’t believe my eyes when I read where it originated from. Guinea? Perhaps an error for Guiana? No, it’s the West African country!! A Bulimulus species in Africa?!?

These specimens (not the first instance!) were intercepted when they were brought into a U.S.A. port. David said it is likely that they first were exported from the Houston area with oil-drilling equipment. “Most of the oil-drilling equipment goes to West African countries from Houston where the containers get contaminated. The port areas must be crawling with invasive snails there. Then when the containers come back to different ports in the US, they are crawling with Texan snails.”

This implies that in several countries lots of American and European species must be present (we know the reports, don’t we?), but this is the first time I hear that an alien species in one country becomes an exotic in a second one and then gets re-imported in the first country at different places. My ‘U-loop’ hypothesis, perhaps logical that it should happen one day, is here reported for the first bulimulid species criss-crossing the ocean.

Gastropods from Misiones, Argentina

Faunal inventories are the first step for any biodiversity research, and although Argentina recently had a partial update (see Cuezzo et al. 2013), the contribution of Gutiérrez et al. published at the same time is welcomed as well. It focusses on the northeastern part of the country, the Prov. Misiones.

Gutierrez f1

The abstract reads as follows: “The Atlantic Forest represents one of the global priority eco-regions for biodiversity conservation. In Argentina, this is represented by the Paranense Forest, which occupies much of the Misiones Province. In this paper, an updated list of land mollusks from Misiones Province is presented, and its species richness was evaluated comparing protected and unprotected areas. For this, we reviewed La Plata Museum Mollusk Collection, updated the literature review, and developed some field work between 2009 and 2010. For the areographic work, a grid (50x50km) was applied to a Misiones province map. In this region, large areas of native vegetation constituting the Paranaense Forest still persist, and include protected areas such as the Iguazu National Park and Puerto Peninsula Provincial Park. These areas have been the most explored at the malacological level (both terrestrial and aquatic environments), a fact that is consistent with the greater number of records found, which may also be the explanation for the highest number of species recorded in the region. A database containing 497 records was compiled. The number of species occurring in this Province was increased from 28 to 56; 11 of which were exotic species. A total of 38 of the species occurred in protected areas and 53 in unprotected areas; and 25 species were micro-mollusks. Orthalicidae was the family with the highest species number (10) and the widest distribution, occupying 16/20 sampling units. Megalobulimus was the genus found in a greater number of sampling units (14/20). The highest values of specific richness of land gastropods were found in Northern Misiones (R=32). This richness was similar to that previously reported for the Tucuman Province, although species occurring in both provinces were mostly different. The richness in Misiones Province border areas, as the Republic of Paraguay and the state of Santa Catarina (Brazil), was about twice that found in the province. The present study showed the existence of poorly explored areas at malacological level, especially in Central and Eastern Misiones. Data presented here will allow focus future sampling efforts on such areas, so patterns of species distribution can be better defined.” The main body of the article is in Spanish.

Gutiérrez, D.E., Núñez, V., Vogler, R.E., Beltramino, A.A. & Rumi, A. Gasterópodos de la provincia Misiones, Argentina. – Revista de Biología  Tropical 61 (4): 1759-1768.