http://www.collembola.org/key/bugguide.htm - Last updated on 2010.04.02 by Frans Janssens
Checklist of the Collembola: Key to the common surface dwelling Collembola from North America

This key is still under construction. Note that missing figures will be provided as soon as possible. Currently, the key is in the feasibility study phase to find out how to integrate in the checklist in a modular way a key that has been generated with DELTA.

Kenneth A. Christiansen, Department of Biology, Grinnell College, PO Box V3, Grinnell, IA 50112-0806, USA
Frans Janssens, Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium

Preface

This pilot pictorial key is designed to aid field identification based on general habitus of live specimens using 5x or lower magnification. The key is developed as a joint effort with the BugGuide.net project of the Iowa State University, USA. All images are courtesy of BugGuide contributors.

Definitions
Common: found by BugGuide contributors.
Surface dwelling: living and actively crawling on the surface of things, such as on water surfaces, on vegetation, on rocks, on bark of trees, on walls of houses; also hiding under bark, stones, vegetation, in leaf litter, in houses.

Version history and picture credits

2010.01.21: Scott Justis: Entomobryomorpha, Poduromorpha, Symphypleona.
2010.01.28: Lynn Bergen: Neanurinae; John F. Carr: Hypogastruridae; John Davis: Onychiuridae; Sam Houston: Tomoceridae; Scott Justis: Bourletiellidae, Isotomidae, Katiannidae; Tom Murray: Dicyrtomidae, Poduridae, Sminthuridae; David E. Reed: Neanuridae partim; Robert Lord Zimlich: Paronellinae.
2010.04.02: Scott Justis: Odontellidae.

Acknowledgements

The authors wish to thank :
Lynn Bergen, John F. Carr, John Davis, Sam Houston, Scott Justis, Tom Murray, David E. Reed, Robert Lord Zimlich, contributing BugGuide macrophotographers;
Vassili Belov, for his constructive comments and cooperation in setting up the interface with BugGuide.

Rationale

The rationale for taxa used and not used as well as subtaxonomic classification for some taxa is to be provided.

Key

Note that no distinction between subtaxa and taxa is made in the key.

   
1(0).   Abdominal tergal segmentation distinct (fig.1a); trunk
          elongate (fig.2a)......................................... 2
        Abdominal tergal segmentation indistinct (fig.1b); trunk
          subglobular (fig.2b)..................................... 11
 

Fig.1.
 

Fig.2.
 
2(1).   Antennae long; legs long; prothoracic tergum indistinct
          (fig.3b).................................................. 3
        Antennae short; legs short; prothoracic tergum distinct
          (fig.3a).................................................. 6
 

Fig.3.
 
3(2).   Third antennal segment much longer than other antennal
          segments (fig.4)............................... Tomoceridae
        Third antennal segment subequal to other antennal segments
          (fig.3b).................................................. 4
 

Fig.4.
 
4(3).   Fourth abdominal segment distinctly longer than other
          abdominal segments (fig.3b)............................... 5
        Fourth abdominal segment subequal to other abdominal segments
          (fig.5)......................................... Isotomidae
 

Fig.5.
 
5(4).   Antennae distinctly longer than body (fig.6).... Paronellinae
        Antennae not distinctly longer than body (fig.3b).............
           ............................................. Entomobryidae
 

Fig.6.
 
6(2).   Body distinctly tuberculate (fig.7)................ Neanurinae
        Body not tuberculate........................................ 7
 

Fig.7.
 
7(6).   Antennae not pyramid-shaped................................. 8
        Antennae pyramid-shaped: broad at basis, narrow at apex
          (fig.8)....................................... Odontellidae
 

Fig.8.
 
8(7).   Eyes absent (fig.9)............................. Onychiuridae
        Eyes present................................................ 9
 

Fig.9.
 
9(8).   Body shape long............................................ 10
        Body shape short (fig.10)........................... Poduridae
 

Fig.10.
 
10(9).  Body setae per segment numerous, 'uncountable' (fig.11).......
           ................................................ Neanuridae 1
        Body setae per segment sparse, at most in 3 transversal rows
          (fig.12).................................... Hypogastruridae
 

Fig.11.
 

Fig.12.
 
11(1).  Antennae as long as or longer than head (fig.13b)........... 12
        Antennae shorter than head (fig.13a).................. Neelidae
 

Fig.13.
 
12(11). Fourth antennal segment much shorter than third antennal
          segment (fig.14)............................... Dicyrtomidae
        Fourth antennal segment subequal or longer than third antennal
          segment.................................................. 13
 

Fig.14.
 
13(12). Abdominal dorsal spinelike macrosetae absent............... 14
        Abdominal dorsal spinelike macrosetae distinctly present
          (fig.15)....................................... Sminthuridae
 

Fig.15.
 
14(13). Fourth antennal segment annulated (fig.16).... Bourletiellidae
        Fourth antennal segment not annulated (fig.17).... Katiannidae

Fig.16.
 

Fig.17.
 


Endnotes

1 Neanuridae without tuberculate body.


Differential diagnoses

Bourletiellidae
Abdominal dorsal spinelike macrosetae absent. Abdominal tergal segmentation indistinct (fig.1b). Antennae as long as or longer than head (fig.13b). Fourth antennal segment subequal or longer than third antennal segment. Fourth antennal segment annulated (fig.16). Trunk subglobular (fig.2b).

Dicyrtomidae
Abdominal tergal segmentation indistinct (fig.1b). Antennae as long as or longer than head (fig.13b). Fourth antennal segment much shorter than third antennal segment (fig.14). Trunk subglobular (fig.2b).

Entomobryidae
Abdominal tergal segmentation distinct (fig.1a). Antennae not distinctly longer than body (fig.3b). Antennae long. Fourth abdominal segment distinctly longer than other abdominal segments (fig.3b). Legs long. Prothoracic tergum indistinct (fig.3b). Third antennal segment subequal to other antennal segments (fig.3b). Trunk elongate (fig.2a).

Hypogastruridae
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Antennae not pyramid-shaped. Body not tuberculate. Body setae per segment sparse, at most in 3 transversal rows (fig.12). Body shape long. Eyes present. Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Isotomidae
Abdominal tergal segmentation distinct (fig.1a). Antennae long. Fourth abdominal segment subequal to other abdominal segments (fig.5). Legs long. Prothoracic tergum indistinct (fig.3b). Third antennal segment subequal to other antennal segments (fig.3b). Trunk elongate (fig.2a).

Katiannidae
Abdominal dorsal spinelike macrosetae absent. Abdominal tergal segmentation indistinct (fig.1b). Antennae as long as or longer than head (fig.13b). Fourth antennal segment subequal or longer than third antennal segment. Fourth antennal segment not annulated (fig.17). Trunk subglobular (fig.2b).

Neanuridae 1
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Antennae not pyramid-shaped. Body not tuberculate. Body setae per segment numerous, ’uncountable’ (fig.11). Body shape long. Eyes present. Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Neanurinae
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Body distinctly tuberculate (fig.7). Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Neelidae
Abdominal tergal segmentation indistinct (fig.1b). Antennae shorter than head (fig.13a). Trunk subglobular (fig.2b).

Odontellidae
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Antennae pyramid-shaped: broad at basis, narrow at apex (fig.8). Body not tuberculate. Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Onychiuridae
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Antennae not pyramid-shaped. Body not tuberculate. Eyes absent (fig.9). Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Paronellinae
Abdominal tergal segmentation distinct (fig.1a). Antennae distinctly longer than body (fig.6). Antennae long. Fourth abdominal segment distinctly longer than other abdominal segments (fig.3b). Legs long. Prothoracic tergum indistinct (fig.3b). Third antennal segment subequal to other antennal segments (fig.3b). Trunk elongate (fig.2a).

Poduridae
Abdominal tergal segmentation distinct (fig.1a). Antennae short. Antennae not pyramid-shaped. Body not tuberculate. Body shape short (fig.10). Eyes present. Legs short. Prothoracic tergum distinct (fig.3a). Trunk elongate (fig.2a).

Sminthuridae
Abdominal dorsal spinelike macrosetae distinctly present (fig.15). Abdominal tergal segmentation indistinct (fig.1b). Antennae as long as or longer than head (fig.13b). Fourth antennal segment subequal or longer than third antennal segment. Trunk subglobular (fig.2b).

Tomoceridae
Abdominal tergal segmentation distinct (fig.1a). Antennae long. Legs long. Prothoracic tergum indistinct (fig.3b). Third antennal segment much longer than other antennal segments (fig.4). Trunk elongate (fig.2a).


References