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Published: 2021-07-23

iTaxoTools 0.1: Kickstarting a specimen-based software toolkit for taxonomists

Department of Evolutionary Biology, Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles 57 rue Cuvier, CP 50, 75005 Paris, France
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles 57 rue Cuvier, CP 50, 75005 Paris, France
Independent researcher, 49 rue Eugène Carrière, 75018 Paris, France
A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Leninsky prospect 33, 119071 Moscow, Russian Federation
Department of Evolutionary Biology, Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
GFBio - Gesellschaft für Biologische Daten e.V., c/o Research II, Campus Ring 1, 28759 Bremen, Germany
Department of Evolutionary Biology, Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106 Braunschweig, Germany
School of Electrical and Computer Engineering, National Technical University of Athens, Iroon Polytechniou St 9, 15780 Athens, Greece
Faculty of Mathematics and Natural Sciences, Institute for Biochemistry and Biology, University of Potsdam, Potsdam, Germany
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles 57 rue Cuvier, CP 50, 75005 Paris, France
Department of Biology, Washington University, 1 Brookings Drive, Saint Louis, MO 63130, USA
integrative taxonomy molecular diagnosis species delimitation ABGD PTP GMYC TR2 DELINEATE Limes.


While powerful and user-friendly software suites exist for phylogenetics, and an impressive cybertaxomic infrastructure of online species databases has been set up in the past two decades, software targeted explicitly at facilitating alpha-taxonomic work, i.e., delimiting and diagnosing species, is still in its infancy. Here we present a project to develop a bioinformatic toolkit for taxonomy, based on open-source Python code, including tools focusing on species delimitation and diagnosis and centered around specimen identifiers. At the core of iTaxoTools is user-friendliness, with numerous autocorrect options for data files and with intuitive graphical user interfaces. Assembled standalone executables for all tools or a suite of tools with a launcher window will be distributed for Windows, Linux, and Mac OS systems, and in the future also implemented on a web server. The initial version (iTaxoTools 0.1) distributed with this paper ( contains graphical user interface (GUI) versions of six species delimitation programs (ABGD, ASAP, DELINEATE, GMYC, PTP, tr2) and a simple threshold-clustering delimitation tool. There are also new Python implementations of existing algorithms, including tools to compute pairwise DNA distances, ultrametric time trees based on non-parametric rate smoothing, species-diagnostic nucleotide positions, and standard morphometric analyses. Other utilities convert among different formats of molecular sequences, geographical coordinates, and units; merge, split and prune sequence files, tables and species partition files; and perform simple statistical tests. As a future perspective, we envisage iTaxoTools to become part of a bioinformatic pipeline for next-generation taxonomy that accelerates the inventory of life while maintaining high-quality species hypotheses. The open source code and binaries of all tools are available from Github ( and further information from the website (


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