Tag Archives: bolivia

Veronicellids recharacterised

Just published: a paper by Rocha & D’ávila on the Veronicellid genera Latipes and Angustipes.

Schermafbeelding 2019-08-08 om 11.58.44

Their abstract is “The genera Angustipes Colosi, 1922 and Latipes Colosi, 1922 were originally proposed as “groups” within the genus Vaginulus Ferrussac, 1822, and since their establishment they have been variously considered valid or invalid until they gained the ultimate status of genus. The descriptions of both genera are general and broadly inclusive, and this fact has complicated taxonomic recognition. Additionally, incomplete descriptions and difficult identification of characteristics in the name-bearing type specimens demonstrate the need to revisit the species and revise the two genera. Herein, we broaden the description of Latipes erinaceus Colosi, 1922 with respect to the circulatory system, the radula, the jaw, the position of entry of the ligation duct in the bursa copulatrix in relation to the canal of the bursa, the origin of the muscle of the penial gland, along with the morphometric characteristics of the phallus, the penial gland, the pedal gland, and the bursa copulatrix. We also propose new differential diagnoses for the genera Angustipes and Latipes, limited to the essential characteristics that enable taxonomic recognition. Hence, we propose the assignment of the species L. erinaceus, Latipes rosilus (Thiele, 1927), Latipes ribeirensis (Thiele, 1927), and Latipes absumptus (Colosi, 1921) to the genus Angustipes, based on the presence of morpho- logical characteristics attributable to this genus, such as the phallus being short and conical; the bursa copulatrix being sessile or short, and lacking a head; the ligation duct inserted near the canal of the bursa; as well as on the similarity in phallus morphology with Angustipes difficilis Colosi, 1922, the type species of this genus“.

Schermafbeelding 2019-08-08 om 11.59.40

The family Veronicellidae is notoriously enigmatic due to the need to use anatomical charcters for classification. This paper is thus a welcome addition to the literature of this family.
Reference:
Rocha, C.A. & D’ávila, S., 2019. New Morphological Characterization of Latipes erinaceus (Gastropoda, Veronicellidae), Differential Diagnosis for the Genera Angustipes and Latipes, and Novel Combinations for Species of Latipes. – Zoological Science (Tokyo), 36 (3):231-241.

A new Megalobulimus from Bolivia

Another single taxon paper by Simone appeared recently, describing a new Bolivian species.

Megalobulimus helicoides is a new species collected in Sucusuma village, Potosí department, Bolivia (Pulmonata, Acavoidae, Strophocheilidae). The species is mainly characterized by the deep suture, by the triangular open umbilicus, relatively small spire and proportionally narrow aperture. The sculpture of the protoconch and teleoconch, the red peristome and the deciduous periostracum indicate that the new species belong to the ‘Megalobulimus oblongus-complex’, which is uncommon in the Andinian region of South America”.

Schermafbeelding 2018-09-09 om 10.43.45

Reference:
Simone, L.R.L., 2018. A new species of Megalobulimus from Potosí, Bolivia (Gastropoda, Strophocheilidae). – Strombus, 24: 1-4.

New paper

Faunal overviews are one of the key stones of biodiversity research, and I’m proud to announce that one of such (modest) contributions has been released fresh from the press.

Synopsis1_f85

The land snail fauna of several South American countries is very incompletely known despite quite extensive literature. For Bolivia there is only an incomplete and outdated list from 1953, Peru is covered by a name list only (2003), and Ecuador has a catalogue for the mainland Orthalicoidea only (2008). Other countries (Brazil, Chile, Argentina) are covered by recent works from local malacologists, and for some others (Colombia, French Guiana) recently overviews have been published, of which especially the one for French Guiana is also very useful for neighbouring countries like Suriname.

This new paper partly aims to fill that gap for Bolivia, Ecuador and Peru treating the minor families of the Orthalicoidea. Covering the three countries this synopsis summarizes all known species and part of their localities (from literature and some major EU museums). Also one new species is described. The full abstract reads: “A faunal overview is presented of the molluscan families Amphibulimidae, Megaspiridae, Odontostomidae, Orthalicidae, Simpulopsidae in Bolivia, Ecuador, and Peru. These Central Andean countries are known for their biodiverse malacofauna, of which the superfamily Orthalicoidea takes relatively a large share. In this paper the five families containing 103 (sub)species, for which systematic information (original publication, type locality, type depository, summarizing literature) and distributional records are presented. All species are illustrated by photographs of the type material or, if this could not be located, by a reproduction of the original figure.
The following new taxon is introduced: Thaumastus (Thaumastus) sumaqwayqu spec. n. Junior subjective synonyms are established for: Plekocheilus (Sparnotion) Pilsbry, 1944 = Plekocheilus (Eudolichotis) Pilsbry, 1896; Scholvienia (Thomsenia) Strebel, 1910 = Scholvienia Strebel, 1910; Sultana (Trachyorthalicus) Strebel, 1909 = Sultana (Metorthalicus) Pilsbry, 1899; Plekocheilus (Eurytus) conspicuus Pilsbry, 1932 = Thaumastus (Thaumastus) hartwegi (Pfeiffer in Philippi, 1846); Zebra gruneri Strebel, 1909 = Orthalicus maracaibensis (Pfeiffer, 1856); Scholvienia jaspidea minor Strebel, 1910 = Scholvienia alutacea (Reeve, 1850); Bulimus bifasciatus unicolor Philippi 1869 = Scholvienia brephoides (d’Orbigny, 1835). A new status is given to Plekocheilus mcgintyi ‘Pilsbry’ H.B. Baker, 1963 (subspecies of Bulinus piperitus Sowerby I, 1837); Strophocheilus superstriatus var. prodeflexus Pilsbry, 1895 (subspecies of Bulinus piperitus Sowerby I, 1837); Thaumastus (Quechua) salteri maximus Weyrauch, 1967 (subspecies of Thaumastus (Quechua) olmosensis Zilch, 1954); Pseudoglandina agitata Weyrauch, 1967 (nomen inquirendum). New combinations are: Clathrorthalicus corydon (Crosse, 1869), and Cyclodontina chuquisacana (Marshall, 1930). Lectotypes are now designated for Bulimus incisus Hupé, 1857 and Bulinus piperitus Sowerby I, 1837”.

Synopsis1_f89

Reference:
Breure, A.S.H. & Mogollón, V., 2016. Synopsis of Central Andean Orthalicoid land snails (Gastropoda, Stylommatophora), excluding Bulimulidae. — ZooKeys 588: 1–199. doi: 10.3897/zookeys.588.7906 (link via Publications)

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.

History matters

During revisions, old collections may pose questions totally unrelated to taxonomy, which are nevertheless crucial to solve in order take the right decision. An example may illustrate this.

 

In the Natural History Museum in London I found material of Bostryx guttatus (Broderip, 1832), which was described from “Peruvia, Cobija or Puerto de la Mar”. Nowadays, Cobija is considered Chile, Región de Antofagasta.

 

Schermafbeelding_2011-02-25_om

 

In the collection, this material was labelled ‘Bolivia’, and the question was: could these specimens possibly be considered syntypes, even if they were seemingly mislabeled?

 

0schermafbeelding_2011-02-25_om

 

For an answer to this question we have to know some facts about the history of this region. In Spanish times this region was part of the Audencia of Charcas, which was a political units of the Viceroyalty of Peru. It was bordered in the south by the Audencia de Chile.

 

 Schermafbeelding 2016-01-10 om 05.02.58

 

Chile became independent in 1818, and Bolivia (till then called ‘Upper Peru’) followed in 1825. Bolivian and Chilean historicans disagree on whether there was access to the sea for this new republic. During the 19th century borders were often not well defined and boundaries in the Atacama had not been well-established when deposits of nitrate, silver and copper were discovered. The dispute began when both countries claimed the territory, leading to the War of the Pacific (1879-1884).
2schermafbeelding_2011-02-25_om

 

It ultimately led to the Chilean annexation of the Tarapacá department and Arica province and of the Bolivian department of Litoral; it left Bolivia as a land-locked country. Later the boundary between Chile and Peru was established with the Tacna-Arica compromise in 1929.

 

The conclusion thus may be, that any material that was collected in this region during the 19th century could bear a label indicating one of the three countries involved, depending on the exact date of labeling. Note that this labeling also could have been done at a later stage, with re-interpretation of the political-administrative situation. Thus some margin of error may always be involved, unless there other sources which are helpful for the interpretation.
My answer to the question of the B. guttatus label is, yes it may be possible to interpret this as a case where ‘Bolivia’ was correct at the time of labeling, where the locality of collection now belongs to Chile.

 

Source: http://en.wikipedia.org/wiki/Atacama_border_dispute with related links and references quoted therein.