Tag Archives: streptaxidae

New record for Gulella bicolor in Mexico

A specimen of Huttonella bicolor = Gulella bicolor (Hutton, 1834) was collected from clayey-sandy soil in Tabasco, Mexico, which constitutes its second record in the state and the third in Mexico. This small gastropod is a predator that has mainly spread through tropical and island regions as an exotic species. Its introduction to Asian and Caribbean Islands is noteworthy. Its pupiform shell and the lamella or tooth complex were compared against previous descriptions. In Mexico, this species has been found in northern Veracruz and Tabasco, which confirms that it is spreading along the Gulf of Mexico from the United States towards Brazil. The features of this streptaxid as a potential hazard through its preferred prey are discussed”.

Schermafbeelding 2019-04-08 om 13.47.07

An additional record to the ones given in the paper is the recent mentioning of this species for Belize by Dourson et al. (2018: 315).

Introduced species are often problematic with regard to the native malacofauna, but in this case the authors argue that also additional reasons may be present for keeping a close eye on the further spread of this species. Which is related to exotic species always a good idea to follow and document their distribution.

Reference:
Costillo-Rodriguez, Z.G. et al., 2018. A new record of Huttonella bicolor (Hutton, 1834) (Mollusca, Gastropoda, Streptaxidae) in Mexico. – Acta Zoológica Mexicana (n.s.) 34: e3411181 (6 pp.).

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New streptaxids from Brazil

A new paper on Brazilian streptaxids reveals two new species. The abstract reads: “A large collection of mollusks was recently acquired by the Museu de Zoologia da Universidade de São Paulo (Brazil) from a commercial company. In this collection, the specimens of the family Streptaxidae from Brazil are both diverse and relatively abundant and are examined here. Herein are reported new records of 11 species, greatly extending the geographical range of the following: Rectartemon depressus (Heynemann, 1868), R. iguapensis (Pilsbry, 1930), R. piquetensis (Pilsbry, 1930) and Streptartemon extraneus (Haas, 1955). Additionally, two new species are described: Streptaxis leirae sp. nov. and Streptaxis megahelix sp. nov.”.

Schermafbeelding 2019-01-01 om 13.40.47Schermafbeelding 2019-01-01 om 13.41.16

Reference:
Salvador, R.B., 2018. Notes on a new collection of Streptaxidae (Gastropoda: Stylommatophora) from Brazil, with descriptions of two new species of Streptaxis. – Integrative Systematics, 1: 25-33.

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.

Serra da Capivara

Earlier in 2013 Simone & Casati published a paper on a series of shells from a relatively unknown region in Brazil, the Serra da Capivara.

The abstract is: “Five new species and one new genus are described from the Serra da Capivara, Piauí, Brazil, a region of semi-dry, Caatinga environment. The described taxa are: Odontostomidae: 1) Clinispira insolita, n. gen. n. sp., possessing strange spire inclination and aperture approaching to the shell apex, it looks closely related to Anostoma, Tomigerus and Biotocus; 2) Cyclodontina capivara n. sp., with well-developed axial ribs and 6 teeth at peristome; 3) Anctus prolatus n. sp., very elongated, with aperture lacking teeth; Simpulopsidae: 4) Rhinus gilbertus n. sp., somewhat elongated and relatively well-sculptured; Streptaxidae: 5) Streptartemon molaris n. sp., possessing a very large basalis tooth at peristome. Two subulinids are also reported from the region: 6) Beckianum beckianum (Pfeiffer, 1846), a population with peculiar pointed shell apex and well-developed axial sculpture; 7) Lamellaxis cf. gracilis (Hutton, 1834), a wide-ranged species that merits further investigation. These descriptions show how scanty is our knowledge on northeast Brazilian malacofauna and may raise efforts for its preservation.” All material comes from the same locality, Cave Toca de Cima dos Pilão, Coronel José Dias municipality.

Simone2013f2-6

Clinispira insolita n. gen. n. sp.

Simone2013f16-18

Cyclodontina capivara n. sp.

Simone2013f35-37

Anctus prolatus n. sp.

Simone2013f24-26

Rhinus gilbertus n. sp.

Simone2013f46-47

Streptartemon molaris n. sp.

The new, monotypic genus Clinispira is especially noteworthy, and maybe other species may turn up once this region is better investigated. The study of living specimens should clarify the relationships of the new taxa described by morphological and molecular studies.

Reference:
Simone, L.R.L. & Casati, R. (2013). New land mollusk fauna from Serra da Capivara, Piauí, Brazil, with a new genus and five new species (Gastropoda: Orthalicoidea, Streptaxidae, Subulinidae). – Zootaxa 3683: 145–158.

Photo of the day (143): Streptaxis ?

Today something puzzling.

Alex Popovkin, field botanist in northeastern Bahia, send me several pictures for identification.

This is definitely a subadult, possibly of Streptaxis costulosus (Pfeiffer, 1852), which is known to occur in Bahia. The closest I can get I think…

Thanks Alex!