Tag Archives: helicinidae

Galapagos micromolluscs

An interesting paper was recently published by Miquel & Bungartz on micromolluscs found among Galapagos lichens and bryophytes, including a new species.

The new species is a carnivorous snail, Scolodonta rinae, and this family is reported for the firt time from the Galapagos. Other species that were encountered are Pupisoma galapagorum, P. dioscoricola, Tornatellides chathamensis, Helicina sp., and Succinea sp.

The new species was found on the island of Santa Cruz.

Reference:
Miquel, S.E. & Bungartz, F., 2017. Snails found among herbarium specimens of Galapagos lichens and bryophytes, with the description of Scolodonta rinae (Gastropoda: Scolodontidae), a new species of carnivorous micro-mollusk. – Archiv für Molluskenkunde, 146 (1): 173-186.

Advertisements

Brazilian cave snails

Another freshly pressed paper is by Salvador et al. on Brazilian cave snails. The abstract reads “A sample of land and freshwater snails, mainly pulmonates, was recently collected in caves in Goiás and Bahia states, Brazil. Twenty-one species were found in the material. The following species are reported for the first time for Goiás state: Cecilioides consobrina (Ferussaciidae), Dysopeas muibum and Stenogyra octogyra (Subulinidae), Entodina jekylli and Prohappia besckei (Scolodontidae; also reported for the first time for Bahia state), Pupisoma dioscoricola (Valloniidae). A new species from Goiás is described here-in: Gastrocopta sharae sp. n. (Gastrocoptidae). The new records and species addressed here constitute important findings, helping to fill distributional gaps and improving the knowledge of the local molluscan fauna, an essential step for future conservation efforts”.

schermafbeelding-2017-02-19-om-06-18-59

Besides the species newly reported for the two states, there are also additional records of the following land snails: Helicina angulata Sowerby, 1873 (Helicinidae), Cyclodonta sexdentata (Spix in Wagner, 1827) and Ringicella luetzelburgi Weber, 1925 (Odontotomidae), Happia glaberrima Thiele, 1927 (Scolodontidae), Allopeas micra (d’Orbigny, 1835) and Leptinaria concentrica (Reeve, 1849) (Subulinidae); five species are identified only to genus level.

This study complements earlier studies on the cave malacofauna in Brazil from part of the authors (see here and here).

Reference:
Salvador, R.B., Cavallari, D.C. & Simone, L.R.L., 2017. Taxonomical study on a sample of land and freshwater snails from caves in central Brazil, with description of a new species. – Zoosystema and Evolution, 93 (1): 193-141.

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.

 

Reference:
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.

Bahia snails

Recently Alex Popovkin send me some new photos of snails he found alive during his botanical wanderings. As always these pictures don’t allow for definite identifications, but here is my best guess.

1-P1560547 2-P1560548 3-P1560550 4-P1560552 5-P1560553

Helicina angulata Sowerby, 1873

1-P1560554 2-P1560555 3-P1560556 4-P1560558

 

A Rectartemon species, possibly R. iguapensis (Pilsbry, 1930) or R. piquetensis (Pilsbry, 1930).

A big thanks to Alex for sharing…

New snails from Brazil, Edo. Tocantins

The Brazilian state of Tocantins is relatively less-known, partly due to being a split-off of Goiás state. Since its Cerrado domain has been poorly studied, a paper by Salvador et al. (2015) is a welcome addition to our knowledge.

A sample of land snails, mainly pulmonates, was recently collected in southeastern Tocantins state, Brazil, close to the border with Bahia state. The following species were found in the material, all of them are reported for the first time from Tocantins: Helicina schereri (Helicinidae); Solaropsis fairchildi and Solaropsis rosarium (Camaenidae); Anostoma rossiCyclodontina cf. gemellata and Cyclodontina sectilabris (Odontostomidae); Drymaeus poecilus and Naesiotus carlucioi (Bulimulidae); Streptaxis luetzelburgi (Streptaxidae); Megalobulimus conicus (Strophocheilidae); Beckianum cf. beckianum (Subulinidae). Additionally, Drymaeus dakryodes sp. nov. is formally described herein. The new records and species addressed here constitute important findings, helping to fill distributional gaps and improving the knowledge of the local molluscan fauna. This is an essential step for future conservation efforts.

Salvador etal 2015 f15-23

The new Drymaeus species was found at Taguatinga, 12º21’54”S 46º21’39”W, ~870m. The holotype (fig. 15-16) is MZSP 114874. The specimen of Beckianum beckianum is a sinistral shell, and other sinistral specimens have been reported from Central America.

Reference:
Salvador, R.B., Cavallari, D.C. & Simone, L.R.L., 2015. Taxonomical study on a sample of land snails from southeastern Tocantins State, Brazil, with description of a new species. – Journal of Conchology 42: 67-78.

Santa Catarina new records

Agudo et al. (2014) published nine new records for the fauna of the State Santa Catarina in Brazil.

The following taxa are concerned:
Family Helicinidae
Helicina schereri F. Baker, 1913
Family Assimineidae
Assiminea sp.
Family Subulinidae
Lamellaxis clavulinus (Potiez & Michaud, 1838)
Lamellaxis (Leptopeas) cf. mizius Marcus & Marcus, 1968
Family Bulimulidae [Amphibulimidae]
Plekocheilus (Eurytus) sp. [the specimen shown is mentioned as P. aff. rhodocheilus (Reeve, 1849) in my previous post]
Rhinus cf. longisetus (Moricand, 1846)
Family Amphibulimidae [both Rhinus and Simpulopsis are now placed in the Simpulopsidae sensu Breure & Romero, 2012]
Simpulopsis cf. ovata (Sowerby, 1822)
Family Megalobulimidae
Megalobulimus klappenbachi Leme, 1964
Family Charopidae
Zilchogyra cleliae Weyrauch, 1965

Agudo ea 2014f7

Reference:
AGUDO-PADRÓN, A.I.; LUZ, J.S.; FUNEZ, L.A.; ZERMIANI, A.E., 2014. Nine new records to inventory of continental mollusc species from Santa Catarina State, Central Southern Brazil. Brazilian Journal of Biology Sciences, 1(1): 15-20. Available at: http://revista.rebibio.net/v1n1/3543-4376-01-03.html

Diversity of Helicinidae

Although already presented at the “Magnitude of molluscan diversity – the known and the unknown” Symposium held at the 78th meeting of the American Malacological
Society (2012), Ira Richling’s excellent paper on diversity of the Helicinidae was recently published (Richling, 2014).

Richling2014f2

Presenting a history of helicinid research starting in 1801 (the first taxon described was a Jamaican species), she has analysed the development of the diversity through time and also a number of revisions to compare the number of accepted (sub)species to available names. Under ‘Drawbacks in exploration’ several aspects (listed below in the abstract) are extensively discussed, which have an importance beyond the scope of the paper.

It would be interesting to explore these issues for other (large) land snail families in the (Neo)tropics. One of these issues is the “limited availability of wet preserved material”, which is quite crucial to make advances both in morphological and molecular studies. Unfortunately, the forthcoming implementation of the Nagoya Protocol (cf. Renner et al., 2012) makes things probably worse and opens up the possibilities for unwarranted claims from local scientists and license authorithies for financial expenditures, and more (examples are known of claimed co-authorship for several papers without any content contribution). Given the ongoing crisis in natural history museums, this is an avenue leading to disasters.

Richling2014f4

The full abstract of the paper reads: “Helicinids represent a family of tropical land snails with a distribution range limited to the subtropical and tropical zones of the New World, Australasia, and the Pacific. For an estimate of diversity in this poorly systematically revised group, the total number of described taxa was determined and used for calculations based on analyses of selected case studies with regard to the percentage of valid and new taxa.
Extensive bibliographic searches identified about 1,250 available names, regardless of rank, that were described from 1801 onward. Fiftyeight percent of the names represent New World taxa whose majority (63%) was created before 1880 while the intensive study in most of the
Australasian and Pacific areas started much later with the bulk of taxa described between 1880–1930. An analysis of the distribution of the type localities and the times of descriptions allowed for identification of scarcely- and well-studied areas.
Eight potentially representative case studies of major revisions were compared with respect to changes in described versus “true” diversity. The geographic range covered Costa Rica, Cuba, Jamaica, Lesser Antilles, New Caledonia, northeast Australia, and the Hawaiian and Gambier
Islands. In these studies approximately half of the available names were regarded as synonyms (range from 37 to 72%). On the other hand, 36 to 41% of the recognized diversity represented new species depending on whether a more lumping or splitting approach was considered, the
latter simulated by simply counting subspecies as equal units of diversity. The amount of new taxa ranged from 2% (Cuba) to 90% (Gambier Islands). Under the assumption that six of the studies were representative throughout the area of distribution, worldwide diversity would
range from 770 to 1,140 species or up to 1,400 species if the studies from the Australasian-Pacifi c area were realistic. Although obviously poorly studied, in comparison with an estimate for all continental molluscs of Mexico and Central America by Thompson (2011), helicinids
would still be among the better documented snail families for this region.
The following aspects and their consequences are discussed as most significant drawbacks in the exploration of helicinids: questionable systematic concepts above species level; limited recognized differentiating characters and convergence; species complexes and last, massive
habitat loss, increasingly fragmented distribution and extinction. Another practical aspect is the rather limited availability of wet preserved material”.

References:
Renner, S.C. et al., 2012. Import and export of biological samples from tropical countries—considerations and guidelines for research teams. – Organisms, Diversity & Evolution 12: 81–98.
Richling, I., 2014. Poorly explored jewels of the tropics: Estimating diversity in non-pulmonate land snails of the family Helicinidae (Gastropoda: Neritopsina). – American Malacological Bulletin 32: 246–258.