Folsomia bisetosa

Schulz, Hans-Jürgen & Potapov, Mikhail B., 2010, A new species of Folsomia from mofette fields of the Northwest Czechia (Collembola, Isotomidae), Zootaxa 2553, pp. 60-64 : 63

Key to species of Folsomia bisetosa -complex

1 Microsensillar formula 10/100. 4 prelabral chaetae ..................................................................................................... 2

- Microsensillar formula 10/000. 2 or 3 prelabral chaetae ............................................................................................. 4

2 PAO larger than Ant.I width. Males present .............................................................. F. mofettophila sp.nov. ( Czechia)

- PAO smaller than Ant.I width. Males absent................................................................................................................ 3

3 Distal transversal row on posterior side of manubrium with 3+3 chaetae (chaeta ml1 present). Fewer than 20 common chaetae positioned medially than lateral sensilla on ventrum of Abd. II ............................................................... ................................................................. F. kuznetsovae Potapov & Taskaeva, 2009 (Eastern Europe, not in Arctic)

- Normally 2+2 chaetae in distal transversal row on posterior side of manubrium (chaeta ml1 absent). More than 20 common chaetae positioned medially than lateral sensilla on ventrum of Abd. II ......................................................... ....................................................................... F. bisetosa Gisin, 1953 (Europe (only in Arctic), Asia and N America)

4 Two prelabral chaetae. 2+2 chaetae in distal transversal row on posterior side of manubrium (chaeta ml1 absent)..... .................................................................................................. F. cryptophila Potapov & Babenko, 2000 (N Siberia)

- Three prelabral chaetae. 3+3 chaetae in distal transversal row on posterior side of manubrium (chaeta ml1 absent). Littoral species ................................................ F. bisetosella Fjellberg, 2005 (European coasts of Northern Atlantic)