Mexico
Small Mexican families
01-04-2010 19:27
In the most recent
number of the American Malacological Bulletin a
series of papers was published as a result of the AMS
2008 Leslie Hubricht symnposium on land snails. One
of these papers is by Naranjo-García & Fehy
(2010).
In this paper they discuss the distribution of the lesser represented land snail families in Mexico, based on literature and unpublished data. This concerns only families represented with less than 30 species in the country; in total 34 families.
For a number of families they give distribution maps of species or compiled data at generic level. The current status is discussed of each family. In the discussion distribution patterns are discussed. In the conclusions several states within Mexico are mentioned which are under-sampled.
Despite a vast base of records, lots of work remains to be done by those Neotropical snail lovers residing or visiting Mexico.
Reference:
Naranjo-García, E. & Fehy, N.E., 2010. The lesser families of Mexican terrestrial mollusks. - American Malacological Bulletin 28: 59-80.
In this paper they discuss the distribution of the lesser represented land snail families in Mexico, based on literature and unpublished data. This concerns only families represented with less than 30 species in the country; in total 34 families.
For a number of families they give distribution maps of species or compiled data at generic level. The current status is discussed of each family. In the discussion distribution patterns are discussed. In the conclusions several states within Mexico are mentioned which are under-sampled.
Despite a vast base of records, lots of work remains to be done by those Neotropical snail lovers residing or visiting Mexico.
Reference:
Naranjo-García, E. & Fehy, N.E., 2010. The lesser families of Mexican terrestrial mollusks. - American Malacological Bulletin 28: 59-80.
Orthalicid radulae (5): Spartocentrum
14-01-2010 21:13
These photos are of a
rare Baja Californian species, Spartocentrum
vanduzeei (Hanna, 1923).
From left above, clockwise: overview of radula, central teeth and first lateral, L13-19, L5-9. The formula is C/3 + LM 24/2.
From left above, clockwise: overview of radula, central teeth and first lateral, L13-19, L5-9. The formula is C/3 + LM 24/2.
Orthalicid radulae (4): Berendtia
08-01-2010 12:00
Berendtia
is a monotypic genus
occurring in Mexico, Baja California. One specimen
of B.
taylori (Pfeiffer, 1861) has been dissected
(Breure, 1978:
159), but
the radula has never been figured before.
From upper left, clockwise: central teeth, interaction between rows, LM7-13, LM14-21.
The formula is C3 + LM 30-34/2.
From upper left, clockwise: central teeth, interaction between rows, LM7-13, LM14-21.
The formula is C3 + LM 30-34/2.
New taxa (16): Spiraxidae
05-08-2009 20:10
Fred Thompson recently published a paper on Mexican
spiraxids. Spriaxidae are carnivorous snails and well
represented in Mexico. Five species are reported from
karst limestone ranges that are separated by basins
of non-calcareous soils.
Streptostylella botteriana (Crosse & Fischer, 1869) is redescribed and -figured. This species occurs near Orizaba and Córdoba in Veracruz and only very few specimens are known.
Another poorly known species, recorded for the first time from Oaxaca, is Streptostyla (Eustreptostyla) nicoleti nicoleti (Shuttleowrth, 1852).
Finally, three new species are described in this paper. One is Streptostyla (Eustreptostyla) rupecula n.sp. Type locality: Veracruz, 4 km NE Comalapa (UF 81912). The two others are species of Varicoturris. V. hadra n.sp. is described from Oaxaca, 12 km NW Bethania (UF 423105) and V. elegans n.sp. from the same state on the northeast shore of Presa Miguel Aleman (UF 337226).
V. hadra (4), V. elegans (6) and Streptostyla rupecula (8)
All species are local endemics of tropical wet seasonal forests.
Reference:
Thompson, F.G., 2009. Five landsnails of the family Spiraxidae from southeastern Mexico (Pulmonata: Spiraxidae). - Archiv für Molluskenkunde 138: 63-70.
Streptostylella botteriana (Crosse & Fischer, 1869) is redescribed and -figured. This species occurs near Orizaba and Córdoba in Veracruz and only very few specimens are known.
Another poorly known species, recorded for the first time from Oaxaca, is Streptostyla (Eustreptostyla) nicoleti nicoleti (Shuttleowrth, 1852).
Finally, three new species are described in this paper. One is Streptostyla (Eustreptostyla) rupecula n.sp. Type locality: Veracruz, 4 km NE Comalapa (UF 81912). The two others are species of Varicoturris. V. hadra n.sp. is described from Oaxaca, 12 km NW Bethania (UF 423105) and V. elegans n.sp. from the same state on the northeast shore of Presa Miguel Aleman (UF 337226).
V. hadra (4), V. elegans (6) and Streptostyla rupecula (8)
All species are local endemics of tropical wet seasonal forests.
Reference:
Thompson, F.G., 2009. Five landsnails of the family Spiraxidae from southeastern Mexico (Pulmonata: Spiraxidae). - Archiv für Molluskenkunde 138: 63-70.
Photo of the day (50): Orthalicus
22-05-2009 19:28
This
Orthalicus
ponderosus
Strebel & Pfeffer, 1882 originates from Mexico,
Jalisco, Punta Pérula area and was captured on logs
of
Dalbergia
retusa
when imported in the USA.
Photos taken by Eric McDonald, courtesy of David Robinson.
Photos taken by Eric McDonald, courtesy of David Robinson.
Fragmentation and de-snail-ation
18-07-2008 09:23
The third in a suite on
habitat destruction
and its possible impact on snails. This time Mexico,
where I remember to have travelled through vast
forests in 1974. If I see the map below, I can only
be horrified on what must have been gone.
Almost 50% of the native montane forests existing in 1975 was cleared 25 years later (Cayela et al. 2006). Although deforestation rates are said to be relatively low compared to those in South-East Asia (Mayaux et al. 2005), it is apparent from remote sensing data that large areas of deforestation are to be found in the foothills of the Andes. Agricultural expansion and new settlements are the main drivers.
While some have questioned the deforestation rates, also non-forest habitats are converted at a large extent. Thus, the 1222 species of terrestrial snails on the Red List (Lydeard et al. 2004) seem to me a gross underestimation.
The effects on the snail fauna in the Pacific is well documented (partly invasive species demanded their toll too), but the effect of large-scale deforestation in Latin America seem to have passed unnoticed. To what extent did it affect the land snail fauna? Are some groups more affected than others? Are there examples of 'niche flexibility' that favours survivors?
References:
Cayuela, L., Rey Benayas, J.M. & Echeverria, C. (2006). Clearance and fragmentation of tropical montane forests in the Highlands of Chiapas, Mexico (1975-2000). Forest Ecology and Management, 226, 208-218.
Lydeard, C. et al. (2004). The global decline of nonmarine mollusks. BioScience, 54, 321-330.
Mayaux, P. et al. (2005). Tropical forest cover change in the 1990s and options for future monitoring. Philosophical Transactions of the Royal Society London B, 360, 373-384.
Almost 50% of the native montane forests existing in 1975 was cleared 25 years later (Cayela et al. 2006). Although deforestation rates are said to be relatively low compared to those in South-East Asia (Mayaux et al. 2005), it is apparent from remote sensing data that large areas of deforestation are to be found in the foothills of the Andes. Agricultural expansion and new settlements are the main drivers.
While some have questioned the deforestation rates, also non-forest habitats are converted at a large extent. Thus, the 1222 species of terrestrial snails on the Red List (Lydeard et al. 2004) seem to me a gross underestimation.
The effects on the snail fauna in the Pacific is well documented (partly invasive species demanded their toll too), but the effect of large-scale deforestation in Latin America seem to have passed unnoticed. To what extent did it affect the land snail fauna? Are some groups more affected than others? Are there examples of 'niche flexibility' that favours survivors?
References:
Cayuela, L., Rey Benayas, J.M. & Echeverria, C. (2006). Clearance and fragmentation of tropical montane forests in the Highlands of Chiapas, Mexico (1975-2000). Forest Ecology and Management, 226, 208-218.
Lydeard, C. et al. (2004). The global decline of nonmarine mollusks. BioScience, 54, 321-330.
Mayaux, P. et al. (2005). Tropical forest cover change in the 1990s and options for future monitoring. Philosophical Transactions of the Royal Society London B, 360, 373-384.
Checklist of Mexico and Central America
21-06-2008 12:36
This week Fred Thompson published his
Checklist and bibliography of the
land and freshwater snails of Mexico and Central
America.
It is a very impressive work, bringing together
all information on taxa from this vast and
interesting area. All together it list 1491
species, 278 subspecies, all native, and 20
introduced species. Of these, terrestrial species
number 1139 (130 operculates, 1109 pulmonates).
The importance of this work, even without any revisionary work or photographs, is large. And it will be an invaluable source of reference and future research, both in the short and long term.
By making the publication free online at the website of the Florida Museum of Natural History, it will undoubtedly stimulate the interest of malacologists in Mexico and Central America.
Chapeau Fred!
The importance of this work, even without any revisionary work or photographs, is large. And it will be an invaluable source of reference and future research, both in the short and long term.
By making the publication free online at the website of the Florida Museum of Natural History, it will undoubtedly stimulate the interest of malacologists in Mexico and Central America.
Chapeau Fred!