Nota científica

 

New records of Mexican Tardigrada

 

Nuevos registros de Tardigrada mexicanos

 

Łukasz Kaczmarek^1*, Dawid Diduszko¹ and Łukasz Michalczyk²

 

¹ Department of Animal Taxonomy and Ecology, A. Mickiewicz University. Umultowska 89, 61–614 Poznań, Poland.^*kaczmar@amu.edu.pl

² School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom.

 

Recibido: 24 enero 2011;
aceptado: 14 marzo 2011

 

Abstract

In 9 moss samples collected from Mexico, 6 tardigrade species, including 4 new records for the country, were found. The new records raise the number of known Mexican water bear species to forty–one. We provide a full list of the known Mexican tardigrade species and discuss some biogeographical and taxonomic issues.

Key words: Eutardigrada, Heterotardigrada, fauna.

 

Resumen

En 9 muestras de musgo recolectadas en México, se encontraron 6 especies de tardígrados, incluyendo 4 nuevos registros para el país. Los nuevos registros incrementaron a 41 el número de especies de tardígrados mexicanos conocidos. Se proporciona una lista completa de tardígrados mexicanos conocidos y se discuten algunas cuestiones biogeográficas y taxonómicas.

Palabras clave: Eutardigrada, Heterotardigrada, fauna.

 

The tardigrade fauna of Mexico has been studied occasionally and in consequence it is very poorly known. To date 37 tardigrade species have been reported from only 8 of the 31 Mexican states, and 7 papers have been published on tardigrade fauna of Mexico: Heinis (1911), May (1948), Schuster (1971), Beasley (1972), Claps and Rossi (2002), Pilato and Lisi (2006), and Beasley et al. (2008). In this paper we provide a full list of tardigrade species previously reported from Mexico and include 4 new records found during this study. Additionally, some biogeographical and taxonomical remarks are provided on the species reported from the country.

Nine moss samples were collected by the second author from Campeche, Chiapas, Mexico and Oaxaca states in the southern part of Mexico (North and Central America). Tardigrades and/or their eggs were found only in 3 samples (see the list below). All specimens were mounted on microscopic slides in Hoyer's medium. Observations and photomicrographs were taken using Phase Contrast Microscopy (PCM). Species were determined mainly on the basis of the key to the World Tardigrada (Ramazzotti and Maucci, 1983) and original descriptions.

The list of localities from which positive samples were collected is as follows. 1, Chiapas State, San Juan Chamula, mosses from soil, 29.10.2007: 24 specimens + 5 eggs. 2, Chiapas State, Palenque, mosses from stone, 15.10.2007: 48 specimens + 10 eggs. 3, Oaxaca State, Monte Alban, ancient ruins of the Zapoteca culture, mosses from soil, 10.10.2007: 56 specimens + 3 eggs.

(*new record for Mexico)
Echiniscus viridissimus Péterfi, 1956*
Material examined in this study: 19 specimens.
Locality. 3.
Remarks. New species report for Mexico. Up to now it has been recorded only from Europe, and South and North America (McInnes, 1994).

Milnesium cf. tardigradum tardigradum Doyère, 1840
Material examined in this study: 3 specimens.
Locality. 2.
Remarks. Cosmopolitan species, recorded from many localities throughout the world; however, older reports should be verified given recent descriptions of many new species within the genus (Tumanov, 2006).

Macrobiotus alvaroi Pilato and Kaczmarek, 2007*
Material examined in this study: 35 specimens and 8 eggs.
Locality. 2.
Remarks. This is the second report of this species and also the first report outside the type locality (Costa Rica) (Pilato and Kaczmarek, 2007).

Macrobiotus coronatus de Barros, 1942
Material examined in this study: 37 specimens and 3 eggs.
Locality. 3.
Remarks. Species recorded from many localities in Europe, Asia, New Zealand, North, Central and South America and Antarctica (McInnes, 1994). According to Pilato et al. (2000), the only confirmed localities are in South America. This is the first confirmed record of this species in Central America.

Macrobiotus persimilis Binda and Pilato, 1972*
Material examined in this study: 24 specimens and 5 eggs.
Locality.1.
Remarks. New species for Mexico. Up to now this species was known only from southern Europe, northern Africa, Australia and Greenland (McInnes, 1994).

Macrobiotus terminalis Bertolani and Rebecchi, 1993*
Material examined in this study: 10 specimens and 2 eggs.
Locality.3
Remarks. New species for Mexico. Up to now this species was known only from southern Europe (Bertolani and Rebecchi, 1993).

This paper adds 4 new records to a short list of known Mexican tardigrade species (41 species). All these species were reported from only 8 Mexican states whereas in other 23 states data are lacking (Table 1). Moreover, nearly half (16) of the known species are considered cosmopolitan, which means that these records are doubtful and need to be confirmed.

Interestingly, 5 species were reported only once from their type localities. The remaining species are known from a range of biogeographical regions: Neotropical (10 species), Nearctic (6), Palearctic (6), Holarctic (3), Afrotropical and Australian (1). A large proportion of Neotropical species suggests a major influence of this region on the tardigrade fauna of Mexico, and the presence of species from the Palearctic, Nearctic and Neotropical regions indicates that Mexico is situated on the border of 2 large biogeographical regions, the Nearctic and Neotropical. Nevertheless, the low number of known Mexican tardigrade species currently prevents any biogeographical analysis.

We are grateful to Alvaro Herrera (INBio, Costa Rica) for his translation of the title and abstract of this manuscript to Spanish. The research was partially supported by The Polish Ministry of Science and Higher Education via the programme "Iuventus plus", grant no. IP2010 015570 to ŁK.

 

Literature cited

Beasley, C. W. 1972. Some tardigrades from Mexico. Southwestern Naturalist 17:21–29.         [ Links ]

Beasley, C. W., Ł. Kaczmarek and Ł. Michalczyk. 2008. Doryphoribius mexicanus, a new species of Tardigrada (Eutardigrada, Hypsibiidae) from Mexico (North America). Proceedings of the Biological Society of Washington 121:34–40.         [ Links ]

Bertolani, R. and L. Rebecchi. 1993. A revision of the Macrobiotus hufelandi group (Tardigrada, Macrobiotidae), with some observations on the taxonomic characters of eutardigrades. Zoologica Scripta 22:127–152.         [ Links ]

Claps, M. C. and G. Rossi. 2002. Tardigrada: 171–186. In Biodiversidad, taxonomía y biogeografía de artrópodos de México: hacia una síntesis de su conocimiento, vol. III, J. Llorente–Bousquets and J. J. Morrone (eds.). Universidad Nacional Autónoma de México, México, D.F. p. 171–186.         [ Links ]

Heinis, F. 1911. Beitrag zur Kenntnis der zentralamericanischen Moosfauna. Revue Suisse de Zoologie 19:253–266.         [ Links ]

May, R. M. 1948. Nouveau genre et espèce de tardigrade du Mexique: Haplomacrobiotus hermosillensis. Bulletin de la Société Zoologique de France 73:95–97.         [ Links ]

McInnes, S. J. 1994. Zoogeographic distribution of terrestrial/freshwater tardigrades from current literature. Journal of Natural History 28:257–352.         [ Links ]

Pilato, G. and Ł. Kaczmarek. 2007. Macrobiotus alvaroi, a new species of eutardigrade (Tardigrada, Macrobiotidae) of the polyopus group from Costa Rica (Central America). Zootaxa 1479:1–7.         [ Links ]

Pilato, G. and O. Lisi. 2006. Notes on some tardigrades from southern Mexico with description of three new species. Zootaxa 1236:53–68.         [ Links ]

Pilato, G., M. G. Binda, A. Napolitano and E. Moncada. 2000. The specific value of Macrobiotus coronatus DeBarros 1942, and description of two new species of the harmsworthi group (Eutardigrada). Bollettino delle sedute dell'Accademia Gioenia di Scienze Naturali 33:103–120.         [ Links ]

Pilato, G., P. Fontoura and O. Lisi. 2007. Remarks on the Echiniscus viridis group, with the description of a new species (Tardigrada, Echiniscidae). In Proceedings of the Tenth International Symposium on Tardigrada, G. Pilato and L. Rebecchi (guest editors). Journal of Limnology 66:33–39.         [ Links ]

Pilato, G., P. Fontoura and O. Lisi. 2008. New description of Echiniscus viridis Murray, 1910 and remarks on the viridis group. New Zealand Journal of Zoology 35:85–92.         [ Links ]

Ramazzotti, G. and W. Maucci. 1983. Il Phylum Tardigrada. Memorie dell'Instituto Italiano di Idrobiologia 41:1–1012.         [ Links ]

Schuster, R. O. 1971. Tardigrada from Barranca del Cobre, Sinaloa and Chihuahua, Mexico. Proceedings of the Biological Society of Washington 84:2130–224.         [ Links ]

Tumanov, D. V. 2006. Five new species of the genus Milnesium (Tardigrada, Eutardigrada, Milnesiidae). Zootaxa 1122:1–23.         [ Links ]