http://www.collembola.org/key/isotomid.htm - Last updated on 2020.03.20 by Frans Janssens
Checklist of the Collembola: Key to the subfamilies of Isotomidae

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.

Mikhail Potapov, Moscow State Pedagogical University, Moscow 129164, Russia
Frans Janssens, Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium

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). Third abdominal segment larger than other abdominal segments....
         .................................................. Isotominae
      Third abdominal segment not larger than other abdominal
        segments.................................................... 2
 
2(1). Anal spines absent............................................ 3
      Anal spines present............................... Anurophorinae 1
 
3(2). Furca absent...................................... Anurophorinae
      Furca present................................................. 4
 
4(3). Furca reduced..................................... Anurophorinae 2
      Furca well developed.......................................... 5
 
5(4). Intugement granulated............................. Pachyotominae
      Intugement smooth............................................. 6
 
6(5). Body sensilla few................................. Anurophorinae 3
      Body sensilla many................................ Proisotominae

Endnotes

1 Anurophorinae with 2-8 anal spines.

2 Anurophorinae with reduced furca, such as in Isotomodella.

3 Anurophorinae with well developed furca, such as in Cryptopygus or Folsomia.

Differential diagnoses

Anurophorinae
Anal spines absent. Furca absent. Third abdominal segment not larger than other abdominal segments.

Anurophorinae 1
Anal spines present. Third abdominal segment not larger than other abdominal segments.

Anurophorinae 2
Anal spines absent. Furca present. Furca reduced. Third abdominal segment not larger than other abdominal segments.

Anurophorinae 3
Anal spines absent. Body sensilla few. Furca present. Furca well developed. Intugement smooth. Third abdominal segment not larger than other abdominal segments.

Isotominae
Third abdominal segment larger than other abdominal segments.

Pachyotominae
Anal spines absent. Furca present. Furca well developed. Intugement granulated. Third abdominal segment not larger than other abdominal segments.

Proisotominae
Anal spines absent. Body sensilla many. Furca present. Furca well developed. Intugement smooth. Third abdominal segment not larger than other abdominal segments.

References