http://www.collembola.org/key/podurpha.htm - Last updated on 2017.06.30 by Frans Janssens
Checklist of the Collembola: Key to the superfamilies of Poduromorpha

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

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).   Dentes absent or vestigial or when present relatively short
          and not ringed (fig.1b)................................... 2
        Dentes more than 3 times as long as manubrium, with distal
          rings of granules (fig.1a)....................... Poduroidea
 

Fig.1.
 
2(1).   Apical organ of fourth antennal segment absent or without many
          blunt projections......................................... 3
        Apical organ of fourth antennal segment with many blunt
          projections (fig.2)......................... Gulgastruroidea
 

Fig.2.
 
3(2).   Sense organ of third antennal segment complex with at least
          six elements, 4-5 outer papillae and 1-3 inner sense
          structures (fig.3a)....................................... 4
        Sense organ of third antennal segment with at most two or
          three protective papillae and two inner sensory structures
          (fig.3b), or with the organ divided into a dorsal and
          ventral section, each bearing more than 2 structures...... 6
 

Fig.3.
 
4(3).   Abdomen with lateral projections (fig.4).....................
           .......................................... Hypogastruroidea 2
        Abdomen without lateral projections......................... 5
 

Fig.4.
 
5(4).   Postantennal organ absent.................... Hypogastruroidea 1
        Postantennal organ present...................... Onychiuroidea 5
 
6(3).   Pseudocelli absent or visible only under scanning electron
          microscope................................................ 7
        Pseudocelli present, at least on antennal base (fig.5) and/or
          or dorsum of fifth abdominal segment.......... Onychiuroidea 6
 

Fig.5.
 
7(6).   Prothoracic tergum with papillae but no setae (fig.6).........
           ............................................. Onychiuroidea 7
        Prothoracic tergum with setae but no papillae............... 8
 

Fig.6.
 
8(7).   Mandible absent or if present then without molar plate
          (fig.7b&c)................................................ 9
        Mandible present and with molar plate (fig.7a)............. 10
 

Fig.7.
 
9(8).   Mucro never trilamellate; between stipe and fulcrum of maxilla
          there is an individualized cardo (fig.7b). Neanuroidea 2
        Mucro often trilamellate (fig.8); between stipe and fulcrum of
          maxilla there is no individualized cardo (fig.7c)...........
           ............................................. Onychiuroidea 8
 

Fig.8.
 
10(8).  Position of anus subterminal..................................
           ............. Neanuroidea:Gomphiocephalidae:Gomphiocephalus 3
        Position of anus terminal or ventral....................... 11
 
11(10). Clothing paucichaetomic; anal spines never 3; setae collophore
          at most 4 + 4; sixth abdominal segment seta a0 absent.......
           .......................................... Hypogastruroidea
        Clothing plurichaetomic; anal spines 3: bilateral pair and
          extra middorsal terminal spine; setae collophore 7-10 +
          7-10; sixth abdominal segment seta a0 present...............
           .............. Onychiuroidea:Triacanthellidae:Triacanthella 4


Endnotes

1 ad partem. Acherongia will key out here.

2 ad partem. Pachytullbergiidae.

3 Monogenic family Gomphiocephalidae nom. nov. (type genus =Gomphiocephalus) with tentative status which is the most basic plesiomorph family of the Neanuroidea (infered from Greenslade & al., 2011).

4 Monogenic family Triacanthellidae nom. nov. (type genus =Triacanthella) with tentative status of the superfamily Onychiuroidea (= Triacanthellidae+(Odontellidae+(Isotogastruridae+(Tullbergiidae+Onychiuridae)))) which is the most basic plesiomorph superfamily of the Poduromorpha (infered from D'Haese, 2002, 2003; Greenslade & al., 2011).

5 ad partem. Onychiuridae.

6 ad partem. Tullbergiidae.

7 ad partem. Isotogastruridae.

8 ad partem. Odontellidae.


Differential diagnoses

Gulgastruroidea
Apical organ of fourth antennal segment with many blunt projections (fig.2). Dentes absent or vestigial or when present relatively short and not ringed (fig.1b).

Hypogastruroidea
Anal spines never 3. Apical organ of fourth antennal segment absent or without many blunt projections. Clothing paucichaetomic. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Mandible present and with molar plate (fig.7a). Position of anus terminal or ventral. Prothoracic tergum with setae but no papillae. Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures. Setae collophore at most 4 + 4. Sixth abdominal segment seta a0 absent.

Hypogastruroidea 1
Abdomen without lateral projections. Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Postantennal organ absent. Sense organ of third antennal segment complex with at least six elements, 4–5 outer papillae and fig.–3 inner sense structures (fig.3a).

Hypogastruroidea 2
Abdomen with lateral projections (fig.4). Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Sense organ of third antennal segment complex with at least six elements, 4–5 outer papillae and 1–3 inner sense structures (fig.3a).

Neanuroidea 2
Apical organ of fourth antennal segment absent or without many blunt projections. Between stipe and fulcrum of maxilla there is an individualized cardo (fig.7b). Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Mandible absent or if present then without molar plate (fig.7b&c). Mucro never trilamellate. Prothoracic tergum with setae but no papillae. Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures.

Neanuroidea:Gomphiocephalidae:Gomphiocephalus 3
Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Mandible present and with molar plate (fig.7a). Position of anus subterminal. Prothoracic tergum with setae but no papillae. Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures.

Onychiuroidea 5
Abdomen without lateral projections. Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Postantennal organ present. Sense organ of third antennal segment complex with at least six elements, 4–5 outer papillae and 1–3 inner sense structures (fig.3a).

Onychiuroidea 6
Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Pseudocelli present, at least on antennal base (fig.5) and/or or dorsum of fifth abdominal segment. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures.

Onychiuroidea 7
Apical organ of fourth antennal segment absent or without many blunt projections. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Prothoracic tergum with papillae but no setae (fig.6). Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures.

Onychiuroidea 8
Apical organ of fourth antennal segment absent or without many blunt projections. Between stipe and fulcrum of maxilla there is no individualized cardo (fig.7c). Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Mandible absent or if present then without molar plate (fig.7b&c). Mucro often trilamellate (fig.8). Prothoracic tergum with setae but no papillae. Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures.

Onychiuroidea:Triacanthellidae:Triacanthella 4
Anal spines 3: bilateral pair and extra middorsal terminal spine. Apical organ of fourth antennal segment absent or without many blunt projections. Clothing plurichaetomic. Dentes absent or vestigial or when present relatively short and not ringed (fig.1b). Mandible present and with molar plate (fig.7a). Position of anus terminal or ventral. Prothoracic tergum with setae but no papillae. Pseudocelli absent or visible only under scanning electron microscope. Sense organ of third antennal segment with at most two or three protective papillae and two inner sensory structures (fig.3b), or with the organ divided into a dorsal and ventral section, each bearing more than 2 structures. Setae collophore 7–10 + 7–10. Sixth abdominal segment seta a0 present.

Poduroidea
Dentes more than 3 times as long as manubrium, with distal rings of granules (fig.1a).


References