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Tarantulas, trapdoor spiders & kin

Jason Bond and Marshal Hedin
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taxon links [up-->]Migidae [up-->]Hexathelidae [up-->]Barychelidae [up-->]Atypoidea [up-->]Idiopidae [up-->]Dipluridae [up-->]Cyrtaucheniidae [up-->]Paratropidae [up-->]Ctenizidae [up-->]Microstigmatidae [up-->]Actinopodidae [up-->]Theraphosidae [up-->]Nemesiidae Monophyly UncertainMonophyly UncertainPhylogenetic position of group is uncertain[down<--]Araneae Interpreting the tree
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The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.

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Summary tree from Hedin & Bond (2006)
Containing group: Araneae


Mygalomorph spiders constitute a moderately diverse group including more than 2,600 described species, currently classified into over 300 genera and 15 families.  Familiar mygalomorphs include tarantulas (also called baboon spiders) and trapdoor spiders, but many other distinctive taxonomic groups exist.  Most mygals are relatively large, long-lived (15-30 years), ground dwelling spiders - the largest spiders in the world are in fact mygalomorphs.   These spiders build a diverse array of silk constructs for prey capture, shelter, and protection (Coyle 1986).  Considered an ancient monophyletic group (Coddington & Levi 1991; Platnick & Gertsch 1976; Raven 1985), mygalomorphs retain several characteristics that are considered primitive for spiders (e.g., two pairs of book lungs, simple spinning structures, etc). Many mygalomorph taxa are dispersal-limited and regionally-endemic, and have long been favorites of biogeographers (e.g., Griswold & Ledford 2001; Platnick 1981).  Mygalomorph lineages have a deep evolutionary history, as reflected in a rich fossil fauna that extends back to the lower Triassic (Selden & Gall 1992), with fossil representatives of several families dating to the mid-Cretaceous (see Eskov & Zonshtein 1990; Penney et al. 2003; Selden 2002).  Recent molecular clock analyses suggest intra-familial divergences date to the Cretaceous  (Hendrixson & Bond 2007), and inter-familial divergences may be as old as 300 Ma (Ayoub et al. 2007). 

Other Names for Mygalomorphae


Ayoub NA, Garb JE, Hedin M, Hayashi CY. 2007. Utility of the nuclear protein-coding gene, elongation factor-1 gamma (EF-1γ), for spider systematics, emphasizing family level relationships of tarantulas and their kin (Araneae: Mygalomorphae). Molecular Phylogenetics and Evolution 42, 394-409.

Bond, J.E., Hedin, M., 2006. A total evidence assessment of the phylogeny of North American euctenizine trapdoor spiders (Araneae, Mygalomorphae, Cyrtaucheniidae) using Bayesian inference. Mol. Phylogen. Evol., in revision.

Coddington, J. A. and H. W. Levi. 1991. Systematics and evolution of spiders (Araneae). Annual Review of Ecology and Systematics 22:565-592.

Coyle, F.A., 1986. The role of silk in prey capture by nonaraneomorph spiders. In: Shear, W.A. (Ed.), Spiders: Webs, Behavior and Evolution. Stanford University Press, Stanford. pp. 269-305.

Dippenaar-Schoeman AS. 2002. Baboon and Trapdoor Spiders of Southern Africa: An Identification Manual Agricultural Research Council, Pretoria, South Africa.

Eskov, K., Zonshtein, S., 1990. First Mesozoic mygalomorph spiders from the Lower Cretaceous of Siberia and Mongolia, with notes on the system and evolution of the infraorder Mygalomorphae (Chelicerata:Araneae). N. Jb. Geol. Paläont. Abh. 178, 325-368.

Goloboff, P.A., 1993. A reanalysis of mygalomorph spider families (Araneae). Am. Mus. Novit. 3056, 1-32.

Griswold, C. Ledford, J., 2001. A monograph of the migid trap-door spiders of Madagascar, with a phylogeny of world genera (Araneae, Mygalomorphae, Migidae). Occ. Pap. Calif. Acad. Sci. 151, 1-120.

Hedin, M and J. E. Bond. 2006. Molecular phylogenetics of the spider infraorder Mygalomorphae using nuclear rRNA genes (18S and 28S): Conflict and agreement with the current system of classification. Molecular Phylogenetics and Evolution, 41, 454-471.

Hendrixson BE, Bond JE (2007) Molecular phylogeny and biogeography of an ancient Holarctic lineage of mygalomorph spiders (Araneae: Antrodiaetidae: Antrodiaetus). Molecular Phylogenetics and Evolution

Penney, D., Wheater, C.P., Selden, P.A., 2003. Resistance of spiders to Cretaceous-Tertiary extinction events. Evolution 57, 2599-2607.

Platnick, N.I., 1977. The hypochiloid spiders: A cladistic analysis, with notes on the Atypoidea (Arachnida, Araneae). Am. Mus. Nov. 2627, 1-23.

Platnick, N.I., 1981. Spider biogeography: past, present, and future. Revue Arachnologique 3, 85-96.

Platnick, N.I., Gertsch, W.J., 1976. The suborders of spiders: A cladistic analysis (Arachnida, Araneae). Am. Mus. Nov. 2607, 1-15.

Raven, R.J., 1985. The spider infraorder Mygalomorphae (Araneae): cladistics and systematics. Bull. Am. Mus. Nat. Hist. 182, 1-180.

Selden PA (2002) First British Mesozoic spider, from Cretaceous amber of the Isle of Wight. Palaeontology 45, 973-983.

Selden, P.A., Gall, J.-C., 1992. A Triassic Mygalomorph spider from the northern Vosges, France. Paleontology 35, 211-235.

Information on the Internet

Title Illustrations
Click on an image to view larger version & data in a new window
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Scientific Name Psalmopoeus irminia
Source Psalmopoeus irminia - Venezuelan Suntiger
Source Collection Flickr
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike License - Version 2.0.
Copyright © 2003 B Smith
Scientific Name Bothriocyrtum californicum
Location San Diego, CA
Specimen Condition Live Specimen
Identified By Marshal Hedin
Behavior prey capture from trapdoor
Sex Female
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0.
Copyright © Marshal Hedin
Scientific Name Calisoga longitarsus
Location Monterey County, California
Acknowledgements collecting assistance: Jim Starrett & Dean Leavitt
Specimen Condition Live Specimen
Identified By Marshal Hedin
Sex Female
Image Use creative commons This media file is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0.
Copyright © Marshal Hedin
About This Page

Jason Bond
East Carolina University, Greenville, North Carolina, USA

Marshal Hedin
San Diego State University, San Diego, California, USA

Correspondence regarding this page should be directed to Jason Bond at and Marshal Hedin at

Page: Tree of Life Mygalomorphae. Tarantulas, trapdoor spiders & kin. Authored by Jason Bond and Marshal Hedin. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Bond, Jason and Marshal Hedin. 2008. Mygalomorphae. Tarantulas, trapdoor spiders & kin. Version 14 September 2008 (under construction). http://tolweb.org/Mygalomorphae/2641/2008.09.14 in The Tree of Life Web Project, http://tolweb.org/

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