http://www.collembola.org/key/hymerini.htm - Last updated on 2017.10.31 by Frans Janssens
Checklist of the Collembola: Key to the genera of Hymenaphorurini

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.

Adrian Smolis, Department of Evolutionary Biology and Ecology, Wroclaw University, 51-148 Wroclaw, Poland
Dariusz Skarzynski, Department of Evolutionary Biology and Ecology, Wroclaw University, 51-148 Wroclaw, Poland
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 antennal segment sense organ with papilla-like cuticular
          prominence................................................ 2
        Third antennal segment sense organ without papilla-like
          cuticular prominence...................................... 5
 
2(1).   Furca reduced to small area of fine granulation with 2-4
          posterior setulae; third antennal segment sense organ with
          five papilla; tibiotarsi with 9 or 11 distal setae........ 3
        Furca reduced to small area of fine granulation without
          posterior setulae (fig.1); third antennal segment sense
          organ with four papilla (fig.2); tibiotarsi with 10 distal
          setae............................................. Kennethia
 

Fig.1.
 

Fig.2.
 
3(2).   Areas of stronger granulation absent; furca with two posterior
          setulae; parapseudocelli absent; setae apically pointed;
          body with pseudocelli............................... Arneria
        Areas of stronger granulation present; furca with two or four
          posterior setulae; parapseudocelli absent or present; setae
          apically pointed or macrosetae rod-like and apically blunt;
          body without pseudocelli.................................. 4
 
4(3).   Macrosetae apically pointed; furca with two posterior setulae;
          body without parapseudocelli..................... Reducturus
        Macrosetae rod-like and apically blunt; furca with four
          posterior setulae (fig.3); body with parapseudocelli always
          located outside of areas of coarser granulation. Dinochiurus
 

Fig.3.
 
5(1).   Third abdominal tergum with submedial pseudocelli........... 6
        Third abdominal tergum without submedial pseudocelli....... 10
 
6(5).   Furca reduced to finely granulated area with or without
          posterior setulae; tenaculum absent....................... 7
        Furca reduced to two knobs with 3 + 3 or 4 + 4 setulae;
          tenaculum present......................................... 9
 
7(6).   Labium with five papillae, papilla E present; third antennal
          segment sense organ with five guard setae................. 8
        Labium with four papillae, papilla E absent; third antennal
          segment sense organ with four guard setae..... Hymenaphorura
 
8(7).   Granular areas of fourth abdominal tergum fused together
          midline into one plate; labium 0 type with apically pointed
          papillae; body with parapseudocelli............. Sacaphorura
        Granular areas of fourth abdominal tergum separated by two
          medial parallel rows of smaller granules; labium A thickened
          and apically blunt; body without parapseudocelli............
           ............................................... Vexaphorura
 
9(6).   Body fusiform; antennal area with pseudocelli..... Kalaphorura
        Body oval-eliptical; antennal area without pseudocelli........
           ............................................. Psyllaphorura
 
10(5).  Thoracic and abdominal dorsolateral pseudocelli absent, in
          this position parapseudocelli present.................... 11
        Thoracic and abdominal dorsolateral pseudocelli present.......
           .............................................. Wandaphorura
 
11(10). Furca reduced to a small area of fine granulation with four
          setulae arranged in one row or an arch located in a middle
          part of sternum iv; terga with all setae apically pointed;
          vesicles in postantennal organ of three kinds: simple,
          bilobed and multilobed located perpendicularly or obliquely
          to the long axis of the organ................. Heteraphorura
        Furca reduced to a small depression with two small, posterior
          setae, in contact with the border between abdominal sterna
          iii and iv; terga with two kinds of setae: blunt rod-like
          mesosetae and pointed microsetae; vesicles in postantennal
          organ compound................................ Paronychiurus


Endnotes

1 Probolaphorura Dunger, 1976, and Protaphorurodes Bagnall, 1949, are not included in the key because of insufficient descriptions.


Differential diagnoses

Arneria
Areas of stronger granulation absent. Body with pseudocelli. Furca reduced to small area of fine granulation with 2–4 posterior setulae. Furca with two posterior setulae. Parapseudocelli absent. Setae apically pointed. Third antennal segment sense organ with papilla-like cuticular prominence. Third antennal segment sense organ with five papilla. Tibiotarsi with nine distal setae. Tibiotarsi with 9 or 11 distal setae.

Dinochiurus
Areas of stronger granulation present. Body without pseudocelli. Body with parapseudocelli always located outside of areas of coarser granulation. Furca reduced to small area of fine granulation with fig.2–4 posterior setulae. Furca with four posterior setulae (fig.3). Furca with two or four posterior setulae. Macrosetae rod-like and apically blunt. Parapseudocelli absent or present. Setae apically pointed or macrosetae rod-like and apically blunt. Third antennal segment sense organ with papilla-like cuticular prominence. Third antennal segment sense organ with five papilla. Tibiotarsi with 11 distal setae. Tibiotarsi with 9 or 11 distal setae.

Heteraphorura
Furca reduced to a small area of fine granulation with four setulae arranged in one row or an arch located in a middle part of sternum iv. Terga with all setae apically pointed. Third abdominal tergum without submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Thoracic and abdominal dorsolateral pseudocelli absent, in this position parapseudocelli present. Vesicles in postantennal organ of three kinds: simple, bilobed and multilobed located perpendicularly or obliquely to the long axis of the organ.

Hymenaphorura
Furca reduced to finely granulated area with or without posterior setulae. Labium with four papillae, papilla E absent. Tenaculum absent. Third abdominal tergum with submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Third antennal segment sense organ with four guard setae.

Kalaphorura
Antennal area with pseudocelli. Body fusiform. Furca reduced to two knobs with 3 + 3 or 4 + 4 setulae. Tenaculum present. Third abdominal tergum with submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence.

Kennethia
Furca reduced to small area of fine granulation without posterior setulae (fig.1). Third antennal segment sense organ with papilla-like cuticular prominence. Third antennal segment sense organ with four papilla (fig.2). Tibiotarsi with 10 distal setae.

Paronychiurus
Furca reduced to a small depression with two small, posterior setae, in contact with the border between abdominal sterna iii and iv. Terga with two kinds of setae: blunt rod-like mesosetae and pointed microsetae. Third abdominal tergum without submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Thoracic and abdominal dorsolateral pseudocelli absent, in this position parapseudocelli present. Vesicles in postantennal organ compound.

Psyllaphorura
Antennal area without pseudocelli. Body oval-eliptical. Furca reduced to two knobs with 3 + 3 or 4 + 4 setulae. Tenaculum present. Third abdominal tergum with submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence.

Reducturus
Areas of stronger granulation present. Body without pseudocelli. Body without parapseudocelli. Furca reduced to small area of fine granulation with 2–4 posterior setulae. Furca with two posterior setulae. Furca with two or four posterior setulae. Macrosetae apically pointed. Parapseudocelli absent or present. Setae apically pointed or macrosetae rod-like and apically blunt. Third antennal segment sense organ with papilla-like cuticular prominence. Third antennal segment sense organ with five papilla. Tibiotarsi with 11 distal setae. Tibiotarsi with 9 or 11 distal setae.

Sacaphorura
Body with parapseudocelli. Furca reduced to finely granulated area with or without posterior setulae. Granular areas of fourth abdominal tergum fused together midline into one plate. Labium 0 type with apically pointed papillae. Labium with five papillae, papilla E present. Tenaculum absent. Third abdominal tergum with submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Third antennal segment sense organ with five guard setae.

Vexaphorura
Body without parapseudocelli. Furca reduced to finely granulated area with or without posterior setulae. Granular areas of fourth abdominal tergum separated by two medial parallel rows of smaller granules. Labium A thickened and apically blunt. Labium with five papillae, papilla E present. Tenaculum absent. Third abdominal tergum with submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Third antennal segment sense organ with five guard setae.

Wandaphorura
Third abdominal tergum without submedial pseudocelli. Third antennal segment sense organ without papilla-like cuticular prominence. Thoracic and abdominal dorsolateral pseudocelli present.


References