Biodiversity and Conservation

, Volume 16, Issue 4, pp 1063–1086 | Cite as

Analysis of the species description process for a little known invertebrate group: the limnoterrestrial tardigrades (Bilateria, Tardigrada)

  • Noemí Guil
  • Francisco J. Cabrero-Sañudo
Original Paper


This study was designed to examine the entire species description process of limnoterrestrial tardigrades up until the present, and to establish the effects of several variables on this process. Information from monographs, revisions and published papers related to limnoterrestrial tardigrades was assessed using generalized linear models (GLM) and variance partition. Our findings reveal the tardigrade species description process fails to show an asymptotic tendency. That is, at the current description rate, we will not get to know all the species in the short- or mid-term. The variables examined served to explain about half of the process variance. Species distribution areas and variables related to their presence in each region were the factors found to have the greatest explanatory capacity. Our analysis indicates that insufficient efforts have been invested in the tardigrades compared to other invertebrates (such as Insecta: Coleoptera), and that there is a need for more taxonomists and more extensive sampling areas. Studies such as this will be useful for␣planning future species sampling campaigns, and help us to improve our methodological approach to␣investigations aimed at conservation and the preservation of biodiversity.


Factors determining description process Limnoterrestrial Species description process Tardigrada 



Generalized linear models


Linear regression analysis


Palaearctic region


Afrotropical region


Oriental region


Australian region


Nearctic region


Neotropical region


Antarctic region


taxonomic variables


categorical variables related to the species taxonomic class


distributional variables


continuous variables representing the number of biogeographic regions in which each species exists


a group of categorical variables related to location of each species


variable referred to the biogeographic region in which the species was described


variable related to the biogeographic region of author’s place of origin.


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This work was made possible by a postdoctoral fellowship from the INECOL (Instituto de Ecología, A. C., Xalapa, Veracruz) awarded to FJCS, a pre-doctoral grant from the Comunidad de Madrid, Consejo Superior de Investigaciones Científicas (CSIC) and Museo Nacional de Ciencias Naturales de Madrid awarded to NG, and a Comunidad de Madrid project (number: 07M/0125/2000). We also thank Dr. Jorge M. Lobo, whose comments served to improve our paper, and Dr. Annie Machordom Barbé for further financial support.


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© Springer Science+Business Media B.V. 2006

Authors and Affiliations

  1. 1.Museo Nacional de Ciencias NaturalesDpto Biodiversidad y Biología EvolutivaMadridSpain
  2. 2.Instituto de Ecología, A.C. DptoBiodiversidad y Ecología Animal, Km 2,5Congregación El HayaMéxico
  3. 3.Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeUSA

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