Monthly Archives: January 2012

Photo of the day (131): Porphyrobaphe

Recently Fred Croxen wrote me the following:

I???m a professor of geosciences at Arizona Western College in Yuma, Arizona.  I recently returned from a vacation in Ecuador and while I was exploring the western coast I visited Isla de la Plata, an island about 40 km west-northwest of Puerto Lopez.   See image below:

While touring the island I came upon an excavation that workers were digging for trail maintenance.  In the wall of the excavation were exposed land snail shells.  The shells appeared to be buried between 1.5 to 3 meters below the former surface in several horizons.  The sediments were a mix of alluvial and colluvial deposits in a steep canyon.  I have attached an image of the site.  The guide informed me that these snails were introduced by early peoples.  I???m not sure of the validity of that claim. The shells are definitely old but probably not fossil sensu strictu.  In any event, I salvaged one of the shells of which I supply images.

The first photo shows the site where the shells were found.


These are pictures of the shell for ID.


This is a specimen of Porphyrobaphe iostoma (Reeve, 1849); see my blogpost Photo of the day 109 (20 October 2010) for pictures of fresh specimens.

Curiosities of biological nomenclature

Under this title Mark Isaak has an interesting website ( about remarkable names given by taxonomists. His website is divided into several categories, each with several pages, e.g.:

– Etymology: e.g., named after people, names from mythology, fictional characters, acronyms (I could imagine using encebeus 😉
– Puns: e.g., double meanings, funny-sounding, plays on familiar words;  
– Wordplay: e.g., unusual letter combinations, isograms, anagrams, palindromes and reversals, rhymes and alliterations.

There are many examples given on this website, some of which are from malacology. However, the most vivid description of remarkable names in malacology may be found in Dance (2009). 

For those who like to play with words, or can see the humor of other people playing with them, certainly both the site and the paper are a ‘must-see’.

Dance, S.P., 2009. A name is a name is a name: some thoughts and personal opinions about molluscan scientific names. – Zoologische Mededelingen Leiden 83: 565-576. 

New taxa (31): Holospiridae

Referring to my previous post, the second paper with new Mexican taxa is Thompson & Mihalcik (2011). The paper gives a review of the northern Mexican land snails of the genera Coelostemma Dall, 1895 and Metastoma Strebel, 1880, both of which are classified within the family Holospiridae (Urocoptoidea).

Coelostemma is a genus distributed in northern Mexico and includes 40 species, of which 6 are described as new in this paper:

Coelostemma (C.) gracile. Type locality: San Luis Potos??, 42 km NW San Luis Potos??, 830 m. Holotype UF 337321.

Coelostemma (C.) cordylum. Type locality: Coahuila, Sierra de Candelaria, 14.3 km by road N Puerto de Ventanillas, Ca??on de Ventanillas, 1050 m. Holotype UF 268353.

Coelostemma (C.) costatum. Type locality: Coahuila, Sierra la Paila, canyon 4 km SW Sacraficio, 1300 m. Holotype UF 267697.

Coelostemma (Apertaxis) salpinx. Type locality: San Luis Potos??, 3.5 km ENE Alamitos, 1340 m. Holotype UF 200230.

Coelostemma (Goniapex) scabrum. Type locality: Chihuahua, pass on Highway 16 over northwest end of Sierra Peguis, 1000 m. Holotype UF 317159.

Coelostemma (G.) mendax. Type locality: Chihuahua, 21 km NE Aldama, 1250 m. Holotype UF 317185.

The reference of the family Holospiridae to the Orthalicoidea in the title of the paper, is an oversight of the authors (F.G. Thompson, pers. commun.).

Thompson, F.G. & Mihalcik, E.L., 2011. Land snails of the family Holospiridae from northern Mexico: Coelostemma and Metastoma (Gastropoda: Pulmonata: Orthalicoidea). Archiv f??r Molluskenkunde 140: 245-263.

New taxa (30): Mexistrophia

The well-known specialist of Central American and Caribbean land shells, Fred Thompson, recently published two interesting papers. Today I mention only his paper on Cerionidae (Thompson, 2011); the other paper will follow shortly.

Cerionids are well-known from the Caribbean, where they occur at low elevations. During his extensive field work in Mexico, Thompson found shells in habitats and elevations that were uncharacteristic for Cerion, and he put them as indeterminable “Urocoptidae”. Closer study, also of the anatomy, revealed that these shells should be classified with the family Cerionidae. In this paper three new species are described within a new genus, Mexistrophia. This genus is now known to be distributed in the Mexican states Querétaro, Nuevo León and Hidalgo, and may be quite widespread once anatomical data become available to ascertain their identification.


The type species is M. reticulata, type locality Edo. Querétano, 1.0 km E Pinal de Amoles, 2150 m. Holotype UF 211128.
A second species, M. obsoleta, was found at a nearby location, 15.8 km by road SW Pinal de Amoles, 2585 m. Holotype UF 34298.
Finally, a third species, M. inexpectata, is described from Edo. Nuevo León, 0.5 km N El Refugio, 2360 m. Holotype UF 226407.
All species are narrow-range endemics and inhabit cool temperate conifer forests that are subject to seasonal frosts.

Biogeographically, it is interesting that this group is disjunct from the ‘true’ Cerion, occurring in the West Indies.

Thompson, F.G., 2011. Mexistrophia, a new genus of Cerionidae from Mexico (Gastropoda: Pulmonata: Urocoptoidea). – The Nautilus 125: 182-192.